<?xml version='1.0' encoding='utf-8'?>
<?xml-stylesheet type="text/xml" href="compare-ml.xsl"?>
<!DOCTYPE comparison SYSTEM "comparison.dtd">
<!--
TODO:

* Add intelligent merging of renamed paths.
* Add IDE integration.
* Integration with build/testing management.
* Check-In policies.
* Add Speed (?)
-->
<comparison>
    <meta>
        <implementations>
            <impl id="cvs">
                <name>CVS</name>
                <url>http://www.cvshome.org/</url>
            </impl>
            <impl id="accurev">
                <name>AccuRev</name>
                <url>http://www.accurev.com/</url>
            </impl>
            <impl id="aegis">
                <name>Aegis</name>
                <url>http://aegis.sourceforge.net/</url>
            </impl>
            <impl id="arch">
                <name>Arch</name>
                <url>http://gnuarch.org/</url>
                <fullname>Arch Revision Control System</fullname>
            </impl>
            <impl id="bazaar">
                <name>Bazaar</name>
                <url>http://bazaar-vcs.org/</url>
            </impl>
            <impl id="bitkeeper">
                <name>BitKeeper</name>
                <url>http://www.bitkeeper.com/</url>
            </impl>
            <impl id="clearcase">
                <name>ClearCase</name>
                <url>http://www-306.ibm.com/software/awdtools/clearcase/</url>
                <fullname>IBM Rational ClearCase</fullname>
            </impl>
            <impl id="cmplus">
                <name>CM+</name>
                <url>http://www.neuma.com/</url>
                <vendor>Neuma</vendor>
            </impl>
            <impl id="cmsynergy">
                <name>CMSynergy</name>
                <url>http://www.telelogic.com/products/synergy/index.cfm</url>
                <vendor>Telelogic</vendor>
            </impl>
            <impl id="co-op">
                <name>Co-Op</name>
                <url>http://www.relisoft.com/co_op/</url>
                <fullname>Code Co-Op</fullname>
            </impl>
            <impl id="darcs">
                <name>Darcs</name>
                <url>http://abridgegame.org/darcs/</url>
            </impl>
            <impl id="git">
                <name>Git</name>
                <url>http://git.or.cz/</url>
            </impl>
            <impl id="ls-sync">
                <name>LibreSource Synchronizer</name>
                <url>http://dev.libresource.org/</url>
            </impl>
            <impl id="mercurial">
                <name>Mercurial</name>
                <url>http://www.selenic.com/mercurial/</url>
            </impl>
            <impl id="monotone">
                <name>Monotone</name>
                <url>http://www.venge.net/monotone/</url>
            </impl>
            <impl id="opencm">
                <name>OpenCM</name>
                <url>http://www.opencm.org/</url>
            </impl>
            <impl id="perforce">
                <name>Perforce</name>
                <url>http://www.perforce.com/</url>
            </impl>
            <impl id="purecm">
                <name>PureCM</name>
                <url>http://www.purecm.com/</url>
            </impl>
            <impl id="SourceAnywhere">
                <name>SourceAnywhere</name>
                <url>http://www.dynamsoft.com/Products/SAWStandalone_Overview.aspx</url>
                <vendor>DynamSoft</vendor>
            </impl>
            <impl id="subversion">
                <name>Subversion</name>
                <url>http://subversion.tigris.org/</url>
            </impl>
            <impl id="superversion">
                <name>Superversion</name>
                <url>http://www.superversion.org/</url>
            </impl>
            <impl id="svk">
                <name>svk</name>
                <url>http://svk.elixus.org/</url>
            </impl>
            <impl id="tfs">
                <name>Team Foundation Server</name>
                <url>http://msdn2.microsoft.com/tfs2008/default.aspx</url>
                <vendor>Microsoft Corp.</vendor>
            </impl>
            <impl id="vesta">
                <name>Vesta</name>
                <url>http://www.vestasys.org/</url>
            </impl>
            <impl id="vss">
                <name>Visual SourceSafe</name>
                <url>http://msdn.microsoft.com/ssafe/</url>
                <vendor>Microsoft Corp.</vendor>
            </impl>
        </implementations>
        <timestamp>
            $Id: scm-comparison.xml 313 2008-07-12 07:25:40Z shlomif $
        </timestamp>
    </meta>
    <contents>
<section id="main">
    <title>Version Control System Comparison</title>
    <expl>
        This is a comparison of version-control systems. It is split
        into several categories and sub-categories under which the
        systems are checked.
    </expl>
    <section id="repos_operations">
        <title>Repository Operations</title>
        <section id="atomic_commits">
            <title>Atomic Commits</title>
            <expl>
                Support for atomic commits means that if an
                operation on the repository is interrupted
                in the middle, the repository will not be
                left in an inconsistent state. Are the
                check-in operations atomic, or can
                interrupting an operation leave the
                repository in an intermediate state?
            </expl>
            <compare>
                <s id="cvs">No. CVS commits are not atomic.</s>
                <s id="accurev">Yes. Commits are atomic</s>
                <s id="arch">Yes. Commits are atomic.</s>
                <s id="bazaar">Yes. Commits are atomic.</s>
                <s id="darcs">Yes. Commits are atomic.</s>
                <s id="subversion">Commits are atomic.</s>
                <s id="superversion">Commits are atomic.</s>
                <s id="svk">Commits are atomic.</s>
                <s id="aegis">Commits are atomic.</s>
                <s id="bitkeeper">Yes (but need to verify)</s>
                <s id="mercurial">Yes.</s>
                <s id="monotone">Yes.</s>
                <s id="opencm">Yes. Commits are atomic.</s>
                <s id="perforce">Yes. Commits are atomic.</s>
                <s id="purecm">Yes. Commits are atomic.</s>
                <s id="vesta">Yes. Commits are atomic.</s>
                <s id="co-op">Yes. Commits are atomic.</s>
                <s id="vss">No. VSS commits are not atomic.</s>
                <s id="cmsynergy">Yes. Commits are atomic.</s>
                <s id="cmplus">Yes. Commits are atomic.</s>
                <s id="clearcase">Yes. Commits (checkins) are atomic.</s>
                <s id="ls-sync">Yes. Commits and updates are atomic.</s>
                <s id="SourceAnywhere">Yes. Commits are atomic.</s>
                <s id="git">Yes. Commits are atomic.</s>
                <s id="tfs">Yes. Commits are atomic.</s>
            </compare>
        </section>
        <section id="move">
            <title>Files and Directories Moves or Renames</title>
            <expl>
                Does the system support moving a file or directory to
                a different location while still retaining the history
                of the file? <b>Note:</b> also see the next section
                about intelligent merging of renamed paths.
            </expl>
            <compare>
                <s id="cvs">
                    No. Renames are not supported and a manual one
                    may break history in two.
                </s>
                <s id="accurev">
                    Yes. Renames of both files and directories are supported.
                    Supports controlling of symbolic links as well.
                </s>
                <s id="subversion">Yes. Renames are supported.</s>
                <s id="cmplus">Yes. Both moves and renames are supported, while maintaining history.</s>
                <s id="superversion">No. Renames are not supported.</s>
                <s id="svk">Yes. Renames are supported.</s>
                <s id="arch">Yes. Renames are supported.</s>
                <s id="bazaar">Yes. Renames are supported for files and directories.</s>
                <s id="darcs">Yes. Renames are supported.</s>
                <s id="bitkeeper">Yes. Renames are supported.</s>
                <s id="aegis">Yes. Renames are supported.</s>
                <s id="mercurial">Yes. Renames are supported.</s>
                <s id="monotone">Yes. Renames are supported.</s>
                <s id="opencm">Yes. Renames are supported</s>
                <s id="perforce">
                    Not directly (you copy and then delete but it manages to
                    keep track of the branch)
                </s>
                <s id="purecm">
                    Yes. File renames are directly supported. File and folder
                    moves require creating a new one and deleting the old one.
                    Moved file histories are preserved.
                </s>
                <s id="vesta">
                    Yes.  The unit of checkout/checkin is a directory
                    tree.  Files and directories can be added,
                    deleted, and renamed between versions.
                </s>
                <s id="co-op">Renames of files are supported.
                    Renaming a directory requires creating a new one,
                    moving the files and deleting the old one.
                    Moved file histories are preserved.
                </s>
                <s id="vss">
                    Affects the whole history, it's like renaming a
                    file in the CVS repository. There is a kludgy workaround
                    using "share-rename,move,delete" that gets what you
                    want.
                </s>
                <s id="cmsynergy">Yes. Renames are supported.</s>
                <s id="clearcase">
                  Yes. Directories are first-class controlled entities
                  in Clearcase. Even supports controlling of
                  symbolic/hard links.
                </s>
                <s id="ls-sync">
                    Yes. Renames and move are supported but the working copy
                    needs to be up-to-date before doing a rename/move operation.
                    This operation will be committed directly.
                </s>
                <s id="SourceAnywhere">Yes. Both moves and renames are supported, while maintaining history.</s>
                <s id="git">
                    Renames are supported for most practical
                    purposes.  Git even detects renames when a file has been
                    changed afterward the rename.  However, due to a peculiar
                    repository structure, renames are not recorded
                    explicitly, and Git has to deduce them (which works well
                    in practice).
                </s>
                <s id="tfs">
                  Yes. Both moves and renames are supported,
                  while maintaining history.
                </s>
           </compare>
        </section>
        <section id="intelligent_renames">
            <title>Intelligent Merging after Moves or Renames</title>
            <expl>
                If the system keeps tracks of renames, does it support
                intelligent merging of the files in the history after
                the rename? (For example, changing a file in a renamed
                directory, and trying to merge it).
            </expl>
            <compare>
                <s id="cvs">
                    Renames are not supported at all, much less intelligent
                    ones.
                </s>
                <s id="accurev">
                    Unknown. FILL IN.
                </s>
                <s id="subversion">
                    "svn help me" says "Note: this subcommand is equivalent to
                    a 'copy' and 'delete'." There's <a
                        href="http://subversion.tigris.org/issues/show_bug.cgi?id=898">a
                        bug report about it</a>.
                </s>
                <s id="cmplus">Unknown. FILL IN.</s>
                <s id="superversion">No. Renames are not supported.</s>
                <s id="svk">Same as Subversion.</s>
                <s id="arch">Yes. Renames can be merged intelligently.</s>
                <s id="bazaar">Yes. Renames are intelligent.</s>
                <s id="darcs">Unknown.</s>
                <s id="bitkeeper">Probably Yes.</s>
                <s id="aegis">Unknown. FILL IN.</s>
                <s id="mercurial">
                    No. <a
                        href="http://hgbook.red-bean.com/hgbookch5.html#x9-1030005.4">the
                        Mercurial book says:</a>
                    "When you use the 'hg rename' command, Mercurial makes a
                    copy of each source file, then deletes it and marks the
                    file as removed. "
                </s>
                <s id="monotone">Unknown. FILL IN.</s>
                <s id="opencm">Unknown.</s>
                <s id="perforce">
                    No, renames are not intelligent.
                </s>
                <s id="purecm">
                    Unknown. FILL IN.
                </s>
                <s id="vesta">
                    Unknown. FILL IN.
                </s>
                <s id="co-op">
                    Unkown. FILL IN.
                </s>
                <s id="vss">
                    No, renames are not intelligent.
                </s>
                <s id="cmsynergy">
                    Unknown. FILL IN.
                </s>
                <s id="clearcase">
                    Unknown. FILL IN.
                </s>
                <s id="ls-sync">
                    Unknown. FILL IN.
                </s>
                <s id="SourceAnywhere">
                    Unknown. FILL IN.
                </s>
                <s id="git">
                    As detailed in the <a
                        href="http://git.or.cz/gitwiki/GitFaq#rename-tracking">Git
                        FAQ</a>:
                    "Git has a rename command git mv, but that is just a
                    convenience. The effect is indistinguishable from removing
                    the file and adding another with different name and the
                    same content."
                </s>
                <s id="tfs">
                    Unknown. FILL IN.
                </s>
           </compare>
        </section>
        <section id="copy">
            <title>File and Directories Copies</title>
            <expl>
                Does the version control system support copying
                files or directories to a different location at the
                repository level, while retaining the history?
            </expl>
            <compare>
                <s id="cvs">No. Copies are not supported.</s>
                <s id="accurev">
                    Copying is supported through symbolic links
                    (but all linked files are treated as the same file
                    version).  Moves are fully supported with the history
                    retained.
                </s>
                <s id="subversion">Yes. And it's a very cheap operation (O(1)) that
                    is also utilized for branching.
                </s>
                <s id="cmplus">Yes. An inexpensive operation that can be used for
                    sharing files in multiple places.  On deploy, you have the
                    option of deploying only one of the shared files or all of them.
                </s>
                <s id="superversion">No. Copies are not supported.</s>
                <s id="svk">Yes. Same as subversion.</s>
                <s id="arch">No. Copies of files and directory structures are
                    not supported.
                </s>
                <s id="bazaar">No. Copies are not supported.</s>
                <s id="darcs">No. Copies of files and directory structures are
                    not supported.
                </s>
                <s id="bitkeeper">
                    Yes. Copies are supported.
                </s>
                <s id="aegis">No. Copies are not supported.</s>
                <s id="mercurial">Yes. Copies are supported</s>
                <s id="monotone">Yes. Copies are supported</s>
                <s id="opencm">No. Copies are not supported.</s>
                <s id="perforce">Copies are supported (though, because
                    of its architecture, I don't know how well)
                </s>
                <s id="purecm">Yes. Copies are supported.</s>
                <s id="vesta">
                    Yes.  A new package/branch can be based on any
                    existing version without affecting the past
                    history.  (This is also an O(1) operation.)
                </s>
                <s id="co-op">Copying doesn't retain history, moving does.</s>
                <s id="vss">Yes. Copies are supported up to a point.</s>
                <s id="cmsynergy">Yes, and it's a very cheap operation (update the target
					directory to include the new file/directory).
				</s>
                <s id="clearcase">
                  Yes, through use of hard links. (But some
                  limitations in Windows environments)
                </s>
                <s id="ls-sync">No, copies will start their own history.</s>
                <s id="SourceAnywhere">Copying doesn't retain history, moving does.</s>
                <s id="git">No.  Copies are not supported.</s>
                <s id="tfs">
                  Yes - you can create a branch. But the GUI has no option to
                  view the old history. The <a
                  href="http://msdn.microsoft.com/en-us/tfs2008/bb980963.aspx">
                  Power-Tool tfpt</a> has the option /followbranches to show
                  the history of the file branch's ancestors
                </s>
           </compare>
        </section>
        <section id="repos_clone">
            <title>Remote Repository Replication</title>
            <expl>
                Does the system support cloning a remote repository to get
                a functionally equivalent copy in the local system? That
                should be done without any special access to the remote
                server except for normal repository access.
            </expl>
            <compare>
                <s id="cvs">
                    Indirectly, by using
                    <a href="http://www.cvsup.org/">CVSup</a>
                    by John Polstra (which requires running the cvsupd
                    daemon on the server)
                </s>
                <s id="subversion">
                    Indirectly, by using Chia-liang Kao's
                    <a href="http://search.cpan.org/dist/SVN-Mirror/">SVN::Mirror</a>
                    add-on or Shlomi Fish'
                    <a href="http://search.cpan.org/dist/SVN-Pusher/">SVN-Pusher</a>
                    utility.
                </s>
                <s id="cmplus">Yes. CM+MultiSite can be configured to clone a repository
                    so that it continues to act as a single repository. Options include
                    cloning only from the main site (i.e. not allowing updates from the
                    clone) and restricting the set of files transferred to a cloned site.
                </s>
                <s id="accurev">Yes.</s>
                <s id="superversion">Yes.</s>
                <s id="svk">Yes.</s>
                <s id="arch">Yes.</s>
                <s id="bazaar">Yes.</s>
                <s id="darcs">Yes.</s>
                <s id="bitkeeper">Yes.</s>
                <s id="aegis">Yes.</s>
                <s id="mercurial">Yes.</s>
                <s id="monotone">Yes.</s>
                <s id="opencm">No.</s>
                <s id="perforce">Yes. Via the Perforce Proxy (P4P) tool.</s>
                <s id="purecm">
                    No. (But a proxy feature is planned for
                    inclusion in the next releases.)
                </s>
                <s id="vesta">Yes.  Replication is a fundamental part of the design.</s>
                <s id="co-op">Repositories are always replicated on local machines.
                    There is no central server.
                </s>
                <s id="vss">
                    Not directly possible with the included GUI or
                    command line tools; ssarc and ssrestor might be useable
                </s>
                <s id="cmsynergy">Yes, as long as you have the (more expensive) Distributed package.</s>
                <s id="clearcase">
                  Not really applicable for clearcase, but see next point.
                </s>
                <s id="ls-sync">
                  Yes, but is not documented and its based on the dataflow feature of the
                  LibreSource Synchronizer.
                </s>
                <s id="SourceAnywhere">Not directly possible with the included GUI or command line tools; Some SQL Server tool might be useable.</s>
                <s id="git">Yes.  This is very intrinsic feature of Git.</s>
                <s id="tfs">
                  TFS Proxy is available but the replica isn't an
                  equivalent copy.
                </s>
            </compare>
        </section>
        <section id="push">
            <title>Propagating Changes to Parent Repositories</title>
            <expl>
                Can the system propagate changes from one repository to
                another?
            </expl>
            <compare>
                <s id="cvs">No.</s>
                <s id="accurev">
                    With AccuReplica, the replica server has all the meta-data
                    and  fetches file data as needed by replica users; all
                    write operations pass automatically from the replica to
                    the master server.
                </s>
                <s id="subversion">Yes, using either Chia-Ling Kao's SVN::Mirror
                    script or the svn-push utility by Shlomi Fish.
                </s>
                <s id="cmplus">
                    Yes.  In CM+MultiSite, changes made at the slave are,
                    by default, propagated to the Main(master) library, as well as
                    to all other Clones (slaves).  You may also propagate changes
                    between unrelated repositories containing some of the same source.
                </s>
                <s id="superversion">No.</s>
                <s id="svk">Yes.</s>
                <s id="arch">Yes.</s>
                <s id="bazaar">Yes.</s>
                <s id="darcs">Yes.</s>
                <s id="bitkeeper">Yes.</s>
                <s id="aegis">Yes.</s>
                <s id="mercurial">Yes.</s>
                <s id="monotone">Yes.</s>
                <s id="opencm">No.</s>
                <s id="perforce">Unknown. Probably Not.</s>
                <s id="purecm">No.</s>
                <s id="vesta">
                    Yes.
                </s>
                <s id="co-op">It's a peer-to-peer system,
                    which keeps all replicas of the repository in sync.
                </s>
                <s id="vss">
                    Not directly possible with the included GUI or
                    command line tools; ssarc and ssrestor might be useable
                </s>
                <s id="cmsynergy">Yes, as long as you have the (more expensive) Distributed package.</s>
                <s id="clearcase">Yes, using Clearcase Multisite.</s>
                <s id="ls-sync">Yes, it's what we call a dataflow.</s>
                <s id="SourceAnywhere">Not directly possible with the included GUI or command line tools; Some SQL Server tool might be useable.</s>
                <s id="git">Yes.  (The Linux kernel development process uses this extremely often).</s>
                <s id="tfs">No.</s>
            </compare>
        </section>
        <section id="permissions">
            <title>Repository Permissions</title>
            <expl>
                Is it possible to define permissions on access to different
                parts of a remote repository? Or is access open for all?
            </expl>
            <compare>
                <s id="cvs">
                    Limited. "pre-commit hook scripts" can be used to
                    implement various permissions systems.
                </s>
                <s id="accurev">
                    Yes. Access can be defined per stream (branch) using
                    access control lists.
                </s>
                <s id="arch">
                    Yes. It is possible to define permissions on access to
                    different parts of a remote repository based on the
                    permission systems of the underlying protocol.
                </s>
                <s id="bazaar">
                    Basic access control can be implemented through a
                    contributed hook script.  ACL support for the
                    Bazaar server is planned.
                </s>
                <s id="darcs">
                    No.
                </s>
                <s id="aegis">
                    Yes. Aegis relies on the UNIX permissions system to
                    implement permissions for files in the repository.
                </s>
                <s id="bitkeeper">
                    FILL IN
                </s>
                <s id="subversion">
                    Yes. The WebDAV-based service supports defining HTTP
                    permissions for various directories of the repository.
                </s>
                <s id="cmplus">
                    Yes.  Permissions are defined by data, primarily,
                    not by location.  If location is a part of the data, it may
                    be used to define permissions by location.  Permissions may
                    apply to a branch, file, problem report, test case, etc.
                    Access may be extended based on peer group, manager, and
                    access lists.
                </s>
                <s id="superversion">
                    No.
                </s>
                <s id="svk">
                    Same as subversion.
                </s>
                <s id="mercurial">
                    Yes. It is possible to lock down repositories,
                    subdirectories, or files using hooks.
                </s>
                <s id="monotone">
                    Yes. It is possible to restrict incoming changes
                    from certain sources to be performed only in certain
                    parts of the repository.
                </s>
                <s id="opencm">
                    Permissions are defined on a per-branch
                    basis.
                </s>
                <s id="perforce">
                    Yes. (more than half a dozen of permission levels that can
                    be set in a file by file basis)
                </s>
                <s id="purecm">
                    Yes. (more than half a dozen of permission levels that can
                    be set in a file by file basis)
                </s>
                <s id="vesta">
                    Yes.  Access permissions for each package (the
                    unit of checkout/checkin) can be different.
                    Access permissions for a branch can be different
                    from the basis package.
                </s>
                <s id="co-op">First access (joining the project)
                    requires administrator's approval.
                    Subsequent access to that project is not controlled.
                </s>
                <s id="vss">
                    Project specific permissions (read, write, delete, destroy)
                    can be set per user; but see "Networking Support":
                    this makes "Repository Permissions" a hindrance to
                    accidental damage but cannot prevent intentional damage.
                </s>
                <s id="cmsynergy">No, though a single server can serve many repositories.</s>
                <s id="clearcase">
                  Yes, a unix-like permissions model is used, which maps
                  onto Windows domain-based authentication in
                  multi-platform environments.
                </s>
                <s id="ls-sync">Permissions are set for the whole repository or branch.</s>
                <s id="SourceAnywhere">Yes. SourceAnywhere Server Manager can define access to a repository per user or group and user access rights to a project.</s>
                <s id="git">No, but a single server can serve many repositories.  Also, UNIX permissions can be used to some extent.</s>
                <s id="tfs">
                  Yes. You get set permissions for each team project, folder,
                  file.
                </s>
            </compare>
        </section>
        <section id="changesets">
            <title>Changesets' Support</title>
            <expl>
                Does the repository support changesets? Changesets are a way
                to group a number of modifications that are relevant to each
                other in one atomic package, that can be cancelled or
                propagated as needed.
            </expl>
            <compare>
                <s id="cvs">No. Changes are file-specific.</s>
                <s id="subversion">Partial support. There are implicit
                    changeset that are generated on each commit.
                </s>
                <s id="cmplus">
                    Yes. Change packages are known as updates.  By
                    default, an update is required to make any change.  The
                    update may be checked-in, differenced, promoted, retrieved,
                    propagated, yanked (i.e. removed from history), etc. each in
                    a single operation.  Baseline alignment is performed
                    based on the status (i.e. promotion level) of the update.
                    Updates also record changes to directory structure: move,
                    add, remove.
                </s>
                <s id="accurev">
                    Yes, AccuRev provides robust functionality for change
                    sets (called change packages in AccuRev) including viewing
                    differences by change packages and merging changes from
                    stream to stream by change package.
                </s>
                <s id="superversion">Partial support. Changes are grouped into changesets,
                    but cannot be cancelled invididually yet.
                </s>
                <s id="svk">Same as subversion.
                </s>
                <s id="aegis">
                    Yes. Changesets are supported.
                </s>
                <s id="bitkeeper">
                    Yes. Changesets are supported.
                </s>
                <s id="arch">
                    Yes. Changesets are supported.
                </s>
                <s id="bazaar">
                    Yes. Changesets are supported.
                </s>
                <s id="darcs">
                    Yes. Changesets are supported.
                </s>
                <s id="mercurial">
                    Yes. Changesets are supported.
                </s>
                <s id="monotone">
                    Yes. Changesets are supported.
                </s>
                <s id="opencm">
                    Yes. Changesets are supported.
                </s>
                <s id="perforce">
                    Yes. Changesets are supported.
                </s>
                <s id="purecm">
                    Yes. Changesets are supported.
                </s>
                <s id="vesta">
                    Not exactly.  Vesta uses a related concept of
                    configurations instead, which some has similar
                    properties.
                </s>
                <s id="co-op">Yes. Changesets are the default.</s>
                <s id="vss">No.  Changes are file-specific.</s>
                <s id="cmsynergy">Yes.  Changesets (or tasks) are fundamental
                	to the way Synergy works.</s>
                <s id="clearcase">
                  Not supported in this way. Extensive branching
                  support gives similar benefits. (eg each changeset
                  can be given a branch). Also optional UCM feature
                  gives something like this (each changeset is a
                  "stream").
                </s>
                <s id="ls-sync">
                  Partial support. There are implicit changeset that are generated on
                  each commit.
                </s>
                <s id="SourceAnywhere">Not exactly. SourceAnywhere uses a related concept of configurations instead, which some has similar properties.</s>
                <s id="git">Yes, Changesets are supported, and there's some flexibility in creating them.</s>
                <s id="tfs">Yes. Changesets are only possibility.</s>
           </compare>
        </section>
        <section id="annotate">
            <title>Tracking Line-wise File History</title>
            <expl>
                Does the version control system have an option to track the
                history of the file line-by-line? I.e., can it show for each line
                at which revision it was most recently changed, and by whom?
            </expl>
            <compare>
                <s id="cvs">Yes. cvs annotate</s>
                <s id="accurev">Yes. Available from both the gui and cli.</s>
                <s id="subversion">Yes. (svn blame)</s>
                <s id="cmplus">Yes.  View revision tags. </s>
                <s id="superversion">No.</s>
                <s id="svk">Yes. (svk blame)</s>
                <s id="bitkeeper">Yes. (bk annotate)</s>
                <s id="arch">Not in the command line client, but ViewARCH,
                a web-interface for Arch, has it.</s>
                <s id="bazaar">Yes. (bzr annotate).</s>
                <s id="darcs">Yes. (darcs annotate)</s>
                <s id="mercurial">Yes. (hg annotate)</s>
                <s id="monotone">Yes, as of version 0.19.</s>
                <s id="aegis">Yes. aeannotate</s>
                <s id="opencm">Unknown. Probably not.</s>
                <s id="perforce">Yes, an annotation feature is present.</s>
                <s id="purecm">Yes, annotation is available through the GUI.</s>
                <s id="vesta">
                    No, but it would be easy to implement a tool that
                    did this, as the Vesta repository provides direct
                    filesystem access to all versions.
                </s>
                <s id="co-op">Not directly, but it's possible to compare
                    any two versions using a visual differ.
                </s>
                <s id="vss">Not directly, but it's possible to compare
                    any two versions using a visual differ.
                </s>
                <s id="cmsynergy">Probably, if you're a sufficiently proficient hacker with
					their scripting language.
                </s>
                <s id="clearcase">Yes, "cleartool annotate"</s>
                <s id="ls-sync">
                    Yes, locally without any server connection with the standard graphical
                    Java client.
                </s>
                <s id="SourceAnywhere">Yes. (SAW annotate)</s>
                <s id="git">Yes. (git blame).</s>
                <s id="tfs">Yes. (tf annotate).</s>
           </compare>
        </section>
    </section>
    <section id="features">
        <title>Features</title>
        <section id="work_on_dir">
            <title>Ability to Work only on One Directory of the Repository</title>
            <expl>
                Can the version control system checkout only one directory of
                the repository? Or restrict the check-ins to only one
                directory?
            </expl>
            <compare>
                <s id="cvs">Yes.</s>
                <s id="accurev">
                    Yes. AccuRev provides functionality to define
                    feature streams in which only the subset of code is seen.
                    A group of developers can then be retricted to work only
                    from that stream so they are only allowed to check in
                    changes to that subset of code.
                </s>
                <s id="subversion">Yes.</s>
                <s id="cmplus">
                    Yes.  Any arbitrary set can be checked out
                    and worked on.  Similarly, arbitrary restrictions may be
                    applied for check-in, including file ownership.
                </s>
                <s id="superversion">No.</s>
                <s id="svk">Yes.</s>
                <s id="bitkeeper">No. All changes are made repository-wide.</s>
                <s id="arch">
                    It is possible to commit only a certain directory.
                    However, one must check out the entire repository as a
                    whole.
                </s>
                <s id="bazaar">For checkouts: No. For checkins: Yes.</s>
                <s id="darcs">
                    It is possible to commit only a certain directory.
                    However, one must check out the entire repository as a
                    whole.
                </s>
                <s id="aegis">No. All changes are made repository-wide.</s>
                <s id="mercurial">
                    It is possible to commit changes only in a subset of the
                    tree. There are plans for partial checkouts.
                </s>
                <s id="monotone">
                    It is possible to commit changes only in a subset of the
                    tree. However, one must extract the entire tree to work
                    on it.
                </s>
                <s id="opencm">No. All changes are made to a project as
                    a unit
                </s>
                <s id="perforce">
                    Yes. Changes to a sub-directory of the repository
                    are supported.
                </s>
                <s id="purecm">
                    Yes.
                </s>
                <s id="vesta">
                    Yes and no. The unit of checkout/checkin (called a
                    package) is a directory tree.  Most projects use
                    more than one.  Once created, a package must be
                    checked out/in as a unit.
                </s>
                <s id="co-op">No. All changes are made to a project as
                    a unit, but it's possible to access each file's
                    history separately.
                </s>
                <s id="vss">Yes.</s>
                <s id="cmsynergy">
                    Yes and no.  Files and directories are checked out and in
                    individually, however you have to work in the context of a
                    project, which consists of one or more directories.
                </s>
                <s id="clearcase">Yes, using snapshot view load rules.</s>
                <s id="ls-sync">
                   It is possible to commit only a certain directory. However, one must
                   check out the entire repository as a whole.
                </s>
                <s id="SourceAnywhere">Yes. SourceAnywhere can define the user access right to each project
                 and users can be restricted to work only on the projects they have check out/in right.</s>
             <s id="git">No.  However, commits could be restricted somewhat, see the "Repository Permissions".</s>
                <s id="tfs">Yes.</s>
           </compare>
        </section>
        <section id="tracking_uncommited_changes">
            <title>Tracking Uncommited Changes</title>
            <expl>
                Does the software have an ability to track the changes in the
                working copy that were not yet committed to the repository?
            </expl>
            <compare>
                <s id="cvs">Yes. Using cvs diff</s>
                <s id="accurev">
                    Yes. The functionality is available through both the GUI
                    and the command line interface.
                </s>
                <s id="subversion">Yes. Using svn diff</s>
                <s id="cmplus">
                    Yes. Use Updates | Delta | Delta Update. Or
                    right click a file or directory and do a compare to workspace.
                </s>
                <s id="superversion">Yes. Local changes are detected and shown immediately. Changes can be
                  collected in a local buffer before being committed to the repository.</s>
                <s id="svk">Yes. Using svk diff</s>
                <s id="bitkeeper">Yes. Using bk diff.</s>
                <s id="arch">
                    Yes, using "tla changes".
                </s>
                <s id="bazaar">Yes, using "bzr diff".</s>
                <s id="darcs">
                    Yes, using "darcs whatsnew".
                </s>
                <s id="aegis">Yes. Using aediff</s>
                <s id="mercurial">Yes. Using hg diff.</s>
                <s id="monotone">Yes. In a similar fashion to CVS.</s>
                <s id="opencm">Yes. Using cm diff</s>
                <s id="aegis">Yes. Using aediff.</s>
                <s id="perforce">Yes.</s>
                <s id="purecm">Yes.</s>
                <s id="vesta">
                    Yes.  Intermediate immutable snapshots can be
                    taken during an active checkout (with vadvance).
                    These intermediate versions can be treated just
                    like checked in versions: they can be replicated
                    to other repositories and used as the basis for
                    branches.
                </s>
                <s id="co-op">Yes, using built-in visual differ/editor.</s>
                <s id="vss">Yes, using integrated diff tool.</s>
                <s id="cmsynergy">Yes, either using integrated diff tool or user-configured
					external diff tool</s>
                <s id="clearcase">Yes, "cleartool diff"</s>
                <s id="ls-sync">
                  Yes, with the Synchronizer Studio (default Java client) or with the
                  standard diff command (diff -r . .so6/xxx/REFCOPY/)
                </s>
                <s id="SourceAnywhere">Yes. Using saw diff.</s>
                <s id="git">Yes.
                Also, branches are very lightweight in Git, and
                could be considered a kind of storage for "uncommitted" code in some workflows.
                </s>
                <s id="tfs">
                  Yes. Using tf diff or "Pending Changes" in Visual Studio.
                </s>
            </compare>
        </section>
        <section id="per_file_commit_messages">
            <title>Per-File Commit Messages</title>
            <expl>
                Does the system have a way to assign a per-file commit message
                to the changeset, as well as a per-changeset message?
            </expl>
            <compare>
                <s id="cvs">No. Commit messages are per change.</s>
                <s id="accurev">No. Commit messages are per change.</s>
                <s id="subversion">No. There is no such feature.</s>
                <s id="cmplus">
                    Yes.  Out of the box CM+ is configured to
                    prompt for messages (i.e. comments) only per change.
                    However, the schema is pre-configured so that you may
                    prompt on a per file basis as well (typically done at
                    checkout time as the entire change is normally checked
                    in with a single operation.
                </s>
                <s id="superversion">Yes.</s>
                <s id="svk">No. There is no such feature.</s>
                <s id="bitkeeper">Yes. It is possible to have a per-file
                    commit message</s>
                <s id="arch">
                    No.
                </s>
                <s id="bazaar">
                    With respect to pure Bazaar: No.  At least one
                    plugin (bzr-gtk) supports it though.
                </s>
                <s id="darcs">
                    No.
                </s>
                <s id="mercurial">
                    No.
                </s>
                <s id="monotone">
                    Yes. It is possible to attach a comment to a certain
                    file at a certain revision.
                </s>
                <s id="opencm">
                    Unknown.
                </s>
                <s id="perforce">
                    No. Commit messages are per change.
                </s>
                <s id="purecm">
                    No. Commit messages are per change.
                </s>
                <s id="vesta">
                    Not exactly.  The unit of checkin is a directory,
                    and commit messages are assigned at that level,
                    not to individual files.  Since configurations are
                    also versioned, they also have commit messages.
                </s>
                <s id="co-op">No. Commit messages are per change.
                    They go to all project members and update
                    their repositories.
                </s>
                <s id="vss">Since changesets are not supported, yes.</s>
                <s id="cmsynergy">Yes.</s>
                <s id="clearcase">
                  Yes, assuming a comment on the branch is sufficient
                  for a per-changeset message.
                </s>
                <s id="ls-sync">No. Commit messages are per changeset.</s>
                <s id="SourceAnywhere">No. There is no such feature.</s>
                <s id="git">No. Commit messages are per changeset.</s>
                <s id="tfs">No. Commit messages are per changeset.</s>
           </compare>
        </section>
    </section>
    <section id="technical_status">
        <title>Technical Status</title>
        <section id="documentation">
            <title>Documentation</title>
            <expl>
                How well is the system documented? How easy is it to
                get started using it?
            </expl>
            <compare>
                <s id="cvs">Excellent. There are many online tutorials and
                    resources and an online book. The command line client
                    also provides an online comprehensive help system.
                </s>
                <s id="accurev">
                    Excellent.  There is a full set of documentation available
                    in pdf format available at
                    <a href="http://www.accurev.com/documentation.html">AccuRev
                        Documentation</a> as well as context-sensitive help
                    in the GUI.
                </s>
                <s id="subversion">
                    Very good. There is a free online book and some online
                    tutorials and resources. The book is written in
                    DocBook/XML and so is convertible to many different
                    formats. The command-line client also provides a good
                    online help system that can be used as a reference.
                </s>
                <s id="cmplus">
                    Very good.  There is a self-demo/tutorial
                    to get you started quickly.  Administration is minimal.
                    So normal developer use requires only a 1 to 2 hour
                    training session (or equivalent guide) to introduce you
                    to concepts and capabilities (e.g. like updates, options).
                    Customization documentation is also extensive but should
                    normally be accompanied by a 2-day to 4-day course for
                    GUI, Process, Data and Application set customization.
                </s>

                <s id="superversion">
                    Fairly poor. There are two tutorials, but there is no
                    reference. Installing and getting started with the GUI
                    is very easy though.
                </s>
                <s id="svk">
                    Relatively poor, but improving. There's
                    <a href="http://svkbook.elixus.org/">a work-in-progress
                        book</a> as well as
                    <a href="http://svk.elixus.org/">the Wiki</a> and some
                    external Articles and Tutorials.
                </s>
                <s id="aegis">
                    Medium. The documentation is given in several large scope
                    troff documents, that are only usable as not-so-PDFish
                    PDF documents, and as text documents that lack any
                    formatting. It is very hard to get started using
                    it with the online resources. The content is of good
                    quality, but otherwise not made very accessible.
                </s>
                <s id="arch">
                    Medium. There are two online tutorials and a
                    comprehensive online documentation. The command line
                    client also supplies a reference page. However, some of
                    the documentation is out of date or incomplete.
                </s>
                <s id="bazaar">
                    Excellent.  Apart from online help in the command
                    line client there exist tutorials, a reference
                    card ("Quick Start Guide"), several full fledged
                    guides and references, and documents on
                    specialized topics, such as migration from other
                    VCS systems and different workflows.  The
                    documentation comes in html and plain-text formats.  The
                    API of the underlying library is fully documented.
                    In the UI design of the command line client
                    special attention was paid to make it easy to get
                    started with Bazaar.
                </s>
                <s id="darcs">
                    Good. The manual contains a brief tutorial and a solid
                    reference.  Every sub-command can print its usage.
                    Because the command-set is small and the model is
                    simple, many users find it easy to get started.
                </s>
                <s id="bitkeeper">
                    Very good. There is a comprehensive help at the BitKeeper
                    site. Each command is documented in its own man page,
                    and the client contains a help tool that offers
                    an integrated help system.
                </s>
                <s id="mercurial">
                    Very good.  There is a
                    <a href="http://hgbook.red-bean.com/">companion
                        book</a> and a wiki. Every command has integrated help.
                </s>
                <s id="monotone">
                    Good. There's an overview and tutorial written in Texi,
                    and a man page. The client supplies documentation for
                    every command.
                </s>
                <s id="opencm">
                    Well documented.
                </s>
                <s id="perforce">
                    Very Good (html and command line help)
                </s>
                <s id="purecm">
                    Very Good (html and command line help)
                </s>
                <s id="vesta">
                    Quite thoroughly (HTML, man pages, published
                    papers, a book-length research report).
                </s>
                <s id="co-op">Very good. Step-by-step tutorial and HTML help
                    is included.
                </s>
                <s id="vss">Medium.  Help file which is sometimes useful.
                	However, the interface is reasonably intuitive so
                	documentation isn't needed as much.
                </s>
                <s id="cmsynergy">Medium.  Lots of books, plus somewhat
                	clunky set of HTML pages, but has some radical concepts
                	which can cause real problems really quickly.  They recommend
                	a day's training for basic users, more for more advanced users.
                	Took a while to become fluent.
                </s>
                <s id="clearcase">
                  Extensive online help in Windows Help / UNIX manpage
                  format, also PDF-based documentation. However the
                  complexity of the tool can mean a lengthy ramp-up
                  time.
                </s>
                <s id="ls-sync">
                  Medium. There are an online tutorial and some comprehensive online
                  documentation. Installing and getting started with the GUI is very easy
                  though. (update/commit-next-next-next-finished)
                </s>
                <s id="SourceAnywhere">Good. There's an overview and tutorial on the web site,
                 and integrated help for every command.</s>
             <s id="git">
                 Medium. The short help is too terse and obscure. The man pages are extensive,
                 but tend to be confusing. The are many tutorials.
             </s>
                <s id="tfs">
                  Good. A comprehensive documentation in the MSDN Library.
                  Many Step-by-Step tutorial videos online.
                </s>
            </compare>
        </section>
        <section id="ease_of_deployment">
            <title>Ease of Deployment</title>
            <expl>
                How easy is it to deploy the software? What are
                the dependencies and how can they be satisfied?
            </expl>
            <compare>
                <s id="cvs">
                    Good. Out of being the de-facto standard,
                    CVS is available on most systems and is easy
                    to deploy.
                </s>
                <s id="accurev">
                    Excellent.  All that is required is to download the
                    binaries for the appropriate platform and run the
                    installer.  The installation package is self-contained.  No
                    additional software is needed.  AccuRev supports most UNIX,
                    Linux, and Windows platforms and deploying AccuRev to a
                    multi-platform environment is straight-forward.
                </s>
                <s id="arch">
                    Excellent. An arch service is nothing but a
                    filesystem-space hosted by any of its supported
                    protocols (FTP, SFTP, WebDAV, etc.). The arch client
                    is written in C, and is portable across UNIX systems
                    (and on Win32 only with a UNIX emulation layer).
                </s>
                <s id="bazaar">
                    Very easy.  Bazaar has an installer for MS Windows
                    and packages for some major Linux distributions,
                    FreeBSD, and Mac OS X.  The dependencies for
                    manual installation are listed on the Bazaar
                    website.
                </s>
                <s id="darcs">
                    Very good. darcs requires few external libraries,
                    however you need the Glasgow Haskell Compiler if you
                    cannot find a binary. To start working, just "darcs
                    init".
                </s>
                <s id="bitkeeper">
                    Good. All that is required is downloading a binary
                    for the system and installing it using the installation
                    script. The package is self-contained and is easy to
                    set up.
                </s>
                <s id="aegis">
                    The Aegis binary should be installed as SUID-root, and
                    so requires root privileges to install. It also not very
                    portable to Win32 systems. Other than that, Aegis supports
                    an easy autoconf or RPM/apt-based installation process.
                </s>
                <s id="subversion">
                    A Subversion service requires installing an Apache 2
                    module (if one wishes to use HTTP as the underlying
                    protocol) or its own proprietary server. The client
                    requires only the Subversion-specific logic and the
                    Neon WebDAV library (for HTTP). Installation of the
                    components is quite straightforward, but will require
                    some work, assuming Subversion does not come prepackaged
                    for one's system.
                </s>
                <s id="cmplus">
                    Yes. Typical installation need only be done
                    on the server (with a single shortcut established on the
                    client).  This assumes file system connectivity. For IP
                    only connectivity, installation is also required on
                    remote clients.  Installation is typically a couple of
                    minutes. No dependencies unless web interface is used,
                    in which case an Apache server is required. A download
                    is available from Neuma's web site and takes you right
                    into a self-guided fully working demo version.
                </s>
                <s id="superversion">
                    If Java 1.4 is installed, deployment of Superversion
                    usually takes two clicks.
                </s>
                <s id="svk">
                    In addition to installing subversion, users are required
                    to install the subversion perl bindings and a few modules
                    from CPAN.
                </s>
                <s id="mercurial">
                    Excellent.  Binary packages are available for all
                    popular platforms.  Building from source requires
                    only Python 2.3 (or later) and a C compiler.
                </s>
                <s id="monotone">
                    Excellent. It is possible to copy or compile the executable
                    to the user's machine, without any configuration or
                    external dependencies.
                </s>
                <s id="opencm">
                    Very good. Install the RPM, or build from tarball and
                    install the init script.
                </s>
                <s id="perforce">
                    Very good. Perforce is very easy to deploy.
                </s>
                <s id="purecm">
                    Very good. PureCM is very easy to deploy.
                </s>
                <s id="vesta">
                    Medium to Good.  There is a detailed installation guide
                    for setting it up using a binary kit.  RPMs and
                    Debian packages have been recently released.
                    There are no dependencies on other software. There is a
                    bootstrap package available to build Vesta from using
                    "make".
                </s>
                <s id="co-op">Very easy to deploy, since there is no central
                    server. Can be configured to use e-mail or LAN (or both) for
                    synchronization. For e-mail, requires MAPI-compliant
                    e-mail client.
                </s>
                <s id="vss">
                    Very good - an installation package which does the work.
                    When you create a repository it installs the exe's in a
                    directory and you can run them from there if you need to.
                </s>
                <s id="cmsynergy">
                    Medium. There is a detailed install guide for setting it
                    up using a binary kit and a set of scripts.  However
                    it still took several tries to get it properly installed
                    and configured.  The Windows client has a slightly clunky
                    Windows installer.
                </s>
                <s id="clearcase">
                  Poor. Clearcase is very difficult to install in
                  general. At least, setup for a new site is quite
                  complex. Installing additional servers (eg
                  repository servers) is less so.
                </s>
                <s id="ls-sync">
                  Excellent. It is managed by JavaWebStart with links on any
                  LibreSource repository web page.
                  (links: create workspace, update, commit, studio...)
                </s>
                <s id="SourceAnywhere">Excellent. Dynamsoft SourceAnywhere is extremely easy to install.
                 It is totally written in C++ from scratch,
                  which means that you don't need any additional components
                   and frameworks to support the installation.</s>
               <s id="git">
                   Good.  Binary packages are available
                   for modern platforms.  C compiler and Perl are
                   required. Requires cygwin on Windows, and has some
                   UNIXisms.
               </s>
                <s id="tfs">
                  Installation is quite complex. Needs IIS, MS-SQL Server and
                  Reporting Services. A own installation guide with
                  step-by-step guide is available.
                  Allows separating in data and app tier.
                </s>
           </compare>
        </section>
        <section id="command_set">
            <title>Command Set</title>
            <expl>
                What is the command set? How compatible is it with
                the commands of CVS (the current open-source defacto
                standard)?
            </expl>
            <compare>
                <s id="cvs">
                    A simple command set that includes three most commonly
                    used commands (cvs commit, cvs update and cvs checkout)
                    and several others.
                </s>
                <s id="accurev">
                    Very extensive but not compatible with cvs.
                </s>
                <s id="subversion">
                    A CVS-like command set which is easy to get used to
                    for CVS-users.
                </s>
                <s id="cmplus">
                        CM+ has several dozen commands that can
                    be used both for operation and configuration of the product.
                    As CM+ is change-based, commands are substantially
                    different than CVS.  The GUI is used primarily and implemented
                    on top of the command set.  As well, CM+ covers a full ALM
                    suite and can be extended beyond, so there are many more
                    generic commands for browsing, reporting, etc.
                </s>
                <s id="superversion">
                    There is little need to memorize a command set because
                    all actions take place in a GUI. A part of the terminology
                    used in the application is borrowed from CVS.
                </s>
                <s id="svk">
                    A CVS-like command set which is easy to get used to
                    for CVS-users.
                </s>
                <s id="bitkeeper">
                    A CVS-like command set with some easy-to-get-used-to
                    complications due to its different way of work and
                    philosophy.
                </s>
                <s id="aegis">
                    A complex command set that involves many operations
                    just to get started. Not CVS-compatible. (albeit
                    support for such basic operations was contemplated)
                    Note that Aegis is a Software Configuration Management
                    system and not just a simple version control system,
                    which may justify this extra complexity.
                </s>
                <s id="arch">
                    Many commands are compatible with CVS or BitKeeper. However,
                    there are many other commands for it for different uses.
                    Aliasing of commands is possible so it it may be possible
                    to make it more compatible.
                </s>
                <s id="bazaar">
                    Tries to follow CVS conventions, but deviates
                    where there is a different design.
                </s>
                <s id="darcs">
                    The command set is fairly compact and the core commands
                    are easy to understand.  Follows CVS in a few places,
                    but since the model is different most commands are
                    unique.
                </s>
                <s id="mercurial">
                    Tries to follow CVS conventions, but deviates where there
                    is a different design.
                </s>
                <s id="monotone">
                    Tries to follow CVS conventions, but deviates where there
                    is a different design.
                </s>
                <s id="opencm">
                    A CVS-like command set that is familiar to existing CVS
                    users.
                </s>
                <s id="perforce">
                    Very extensive but not compatible with CVS.
                </s>
                <s id="purecm">
                    A CVS-like command set which is easy to get used to
                    for CVS-users.
                </s>
                <s id="vesta">
                    The command set is unrelated to CVS.  Most of the
                    time, users use about 5 commands.  Few ever need
                    to know more than about 20 commands.
                </s>
                <s id="co-op">Basic commands are compatible with CVS.</s>
                <s id="vss">
                    A bit of an afterthought.  It's possible to do basic
                	things, but it's really geared up for using the GUI.
                </s>
                <s id="cmsynergy">An extensive and powerful command set,
                	which has some CVS similarity, though the architecture
                	is so different that it quickly moves away for anything
                	but the basics.
                </s>
                <s id="clearcase">
                  Excellent. All tools are available through the
                  command-line. Not very compatible with CVS though.
                </s>
                <s id="ls-sync">
                  Basic commands available (commit/update), but it's really simple to
                  use the GUI. Ant task are also available.
                </s>
                <s id="SourceAnywhere">Very extensive but not compatible with CVS.</s>
                <s id="git">Command set is very feature-rich, and not compatible with CVS.</s>
                <s id="tfs">
                  The command set allows more operations than the GUI
                  but isn't compatible with CVS.
                </s>
           </compare>
        </section>
        <section id="networking">
            <title>Networking Support</title>
            <expl>
                How good is the networking integration of the system?
                How compliant is it with existing protocols and infra-structure?
            </expl>
            <compare>
                <s id="cvs">
                    Good. CVS uses a proprietary protocol with various
                    variations for its client/server protocol. This protocol
                    can be tunneled over an SSH-connection to support
                    encryption.
                </s>
                <s id="accurev">
                    Good. (proprietary protocol using TCP/IP)
                </s>
                <s id="arch">
                    Excellent. Arch can utilize a multitude of protocols
                    for its service, which is nothing but a dumb remote
                    filesystem server. Currently supported protocols include
                    FTP, SFTP, WebDAV (remote file access over HTTP),
                    as well as any remote filesystem protocol (NFS, SMB).
                </s>
                <s id="bazaar">
                    Excellent. Works natively over HTTP (read-only),
                    FTP and SFTP without having Bazaar installed at
                    the remote end.  Works over HTTP, SSH and a custom
                    protocol when talking to a remote Bazaar
                    server. Supports RSYNC and WebDAV (experimental)
                    through plugins.
                </s>
                <s id="darcs">
                    Good. Darcs supports getting patches over HTTP, and
                    getting and sending patches over SSH and email.
                </s>
                <s id="subversion">
                    Very good. The Subversion service can use either
                    WebDAV+DeltaV (which is HTTP or HTTPS based) as its
                    underylying protocol, or its own proprietary protocol
                    that can be channeled over an SSH connection.
                </s>
                <s id="cmplus">
                    Very good.  File system connectivity,
                    TCP/IP connectivity and Web connectivity may be
                    intermixed. MultiSite connectivity is over TCP/IP,
                    as is License server. Works well with SSH, NFS, SMB, etc.
                </s>
                <s id="superversion">
                    Good. Network support based on RMI is integrated
                    seamlessly. Encryption and HTTP tunnelling are planned
                    for the near future.
                </s>
                <s id="svk">
                    Very good. svk uses SVN::Mirror to retrieve remote
                    repository. There has been plans to add VCP support
                    to SVN::Mirror so it will be able to mirror from arbitary
                    remote version control systems.
                </s>
                <s id="bitkeeper">
                    Good. Repositories can be checked out from remote
                    over HTTP, and BitKeeper also sports its own proprietary
                    protocol for communicating between one repository and
                    the other.
                </s>
                <s id="aegis">
                    Poor. Aegis is filesystem-oriented and so can be networked
                    only via NFS (network file-system) or a similar protocol.
                    There exists some HTTP-functionality, but it is quite
                    limited.
                </s>
                <s id="mercurial">
                    Excellent.  Uses HTTP or ssh.  Remote access also
                    works safely without locks over read-only network
                    filesystems.
                </s>
                <s id="monotone">
                    Good. Uses a custom protocol called "netsync".
                </s>
                <s id="opencm">
                    Good. Uses its own proprietary client/server protocol.
                </s>
                <s id="perforce">
                    Good. (single TCP/IP socket)
                </s>
                <s id="purecm">
                    Good. (single TCP/IP socket)
                </s>
                <s id="vesta">
                    Networking is inherent to the system.  The
                    repository exports both an NFS interface and an
                    RPC interface.  The checkout and checkin tools
                    automatically contact a remote repository when
                    required to perform an operation.
                </s>
                <s id="co-op">Uses the simplest LAN interface:
                    copying files between shared directories.
                </s>
                <s id="vss">
                    VSS uses a Windows network share which has to be writable
                    for the VSS users (since this means doubling maintenance
                    for new users). Add user in VSS and to share permissions.
                    the share is most often world-writable, as is the default
                    when creating a share) It does not perform well over a
                    slow network connection.
                </s>
                <s id="cmsynergy">Good (single TCP/IP socket)</s>
                <s id="clearcase">
                  Poor. Uses an *extremely* chatty RPC protocol for
                  most clearcase operations, plus NFS or SMB for
                  accessing the files themselves. Typically servers
                  should be deployed locally (ie on the same LAN) as
                  the client workstations for acceptable performance.
                </s>
                <s id="ls-sync">
                  Good. Use of HTTP to get through firwalls.
                </s>
                <s id="SourceAnywhere">Good. (single TCP/IP socket)</s>
                <s id="git">Excellent.  Can use native Git protocol,
                but works over rsync, ssh, HTTP and HTTPS also.</s>
                <s id="tfs">Good. Use of HTTP(S).</s>
            </compare>
        </section>
        <section id="portability">
            <title>Portability</title>
            <expl>
                How portable is the version-control system to various
                operating systems, computer architectures, and other
                types of systems?
            </expl>
            <compare>
                <s id="cvs">
                    Good. Client works on UNIX, Windows and Mac OS.
                    Server works on UNIXes and on Windows with a UNIX
                    emulation layer.
                </s>
                <s id="accurev">
                    Excellent. The server runs on most UNIX, Linux
                    and Windows platforms. The client runs on all of these
                    platforms and on Mac OS X.
                </s>
                <s id="subversion">
                    Excellent. Clients and Servers work on UNIX,
                    Windows and Mac OS X.
                </s>
                <s id="cmplus">
                    Good.  Clients and Servers work on Unix,
                    Linux, and Windows.  MAC OS X port pending.  Moving server
                    from one platform to another is a copy operation only. Can
                    have different platforms for different servers in a MultiSite
                    configuration. Easily configurable Web client also supported.
                    No CR/LF issues. Scripts are all portable as well.
                </s>
                <s id="superversion">
                    Excellent. Clients and servers work on any Java
                    1.4-compatible platform. There is official support
                    for Windows, Linux and OS/2.
                </s>
                <s id="svk">
                    Good. Clients requires subversion and its perl bindings.
                </s>
                <s id="bitkeeper">
                    Very good. Binaries are available for most common UNIX
                    systems and for Windows 98 and above.
                </s>
                <s id="aegis">
                    Medium. The source is portable across all UNIXes,
                    but the Windows version work only using cygwin, and even
                    then not entirely natively.
                </s>
                <s id="arch">
                    Good. The source is portable across all UNIXes,
                    but requires a UNIX emulation layer on Windows. (need to
                    verify). A service can be hosted on any platform
                    that sports a suitable Internet service.
                </s>
                <s id="bazaar">
                    Works on MS Windows, Linux, Mac OS X, FreeBSD,
                    UNIX, and basically on any system that has a
                    recent Python port.  With case-insensitive file
                    systems there are some issues that can be avoided
                    by using a graphical frontend.  On MS Windows
                    there is a plugin to support tracking of symlinks
                    even if they are not supported natively by the
                    file system.
                </s>
                <s id="darcs">
                    Very good. Supports many UNIXes, Mac OS X, and Windows,
                    and is written in a portable language.
                </s>
                <s id="mercurial">
                    Excellent. Runs on all platforms supported by
                    Python.  Repositories are portable across CPU
                    architectures and endian conventions.
                </s>
                <s id="monotone">
                    Excellent. Executable is portable across all UNIXes and
                    Win32.
                </s>
                <s id="opencm">
                    Good. Portable across all UNIX systems.
                </s>
                <s id="perforce">
                    Excellent. Runs on UNIX, Mac OS, BeOS and Windows.
                </s>
                <s id="purecm">
                    Excellent. Client and Server run on Windows, Linux,
                    Solaris and other UNIXes. The client also runs on Mac
                    OS X.
                </s>
                <s id="vesta">
                    Good.  It should be portable to any UNIX system.
                    Currently it runs on Digital/Compaq/HP Tru64 UNIX
                    and Linux on several different CPU architectures.
                    Ports to Solaris and FreeBSD are planned but
                    haven't begun yet.
                </s>
                <s id="co-op">Windows only: starting with Win95.</s>
                <s id="vss">
                    The Microsoft Product is Windows only.
                    <a href="http://www.mainsoft.com/">MainSoft</a>
                    ships a version of it for some UNIX platforms.
                </s>
                <s id="cmsynergy">
                    Very good - various flavours of Unix,
                    Windows (only NT family for the server), VMS, and
                    possibly other systems.
                </s>
                <s id="clearcase">
                  Medium. Available on Windows, and several selected
                  flavours of UNIX (not including MacOS X, or any
                  other Linux other than Red Hat).
                </s>
                <s id="ls-sync">
                  Excellent. Clients and servers work on any Java 1.5-compatible
                  platform. (Windows, Linux and Mac OS X )
                </s>
                <s id="SourceAnywhere">Good. The server runs on Windows only.
                 Clients can work on any platform that SWT (Standard Widget Toolkit) supports,
                  including Windows, Linux, Mac, Solaris, AIX, HP-UX, SCO Unix, FreeBSD and so on.</s>
              <s id="git">
                  The client works on most UNIXes, but not on native MS-Windows. The cygwin build
                  seems to be workable, though.
              </s>
              <s id="tfs">
                The Server and Client needs Windows. A thirdparty company,
                Teamprise, has developed a client for Eclipse, which means
                Linux, Mac and other UNIXes support. The Project SvnBridge
                allows access using SVN clients but needs to run on Windows.
              </s>
            </compare>
        </section>
    </section>
    <section id="user_interaces">
        <title>User Interfaces</title>
        <section id="web_interface">
            <title>Web Interface</title>
            <expl>
                Does the system have a WWW-based interface that can be
                used to browse the tree and the various revisions of the
                files, perform arbitrary diffs, etc?
            </expl>
            <compare>
                <s id="cvs">Yes.
                    <a href="http://www.freebsd.org/projects/cvsweb.html">CVSweb</a>,
                    <a href="http://www.viewvc.org/">ViewVC</a>,
                    <a href="http://www.horde.org/chora/">Chora</a>,
                    and <a href="http://wwcvs.republika.pl/">wwCVS</a>.
                </s>
                <s id="accurev">No.</s>
                <s id="bitkeeper">Yes. Its own built-in web-interface.</s>
                <s id="subversion">Yes.
                    <a href="http://www.viewvc.org/">ViewVC</a>,
                    <a href="http://freshmeat.net/projects/svnweb/">SVN::Web</a>,
                    <a href="http://websvn.tigris.org/">WebSVN</a>,
                    <a href="http://viewsvn.berlios.de/">ViewSVN</a>,
                    <a href="http://www.outoforder.cc/projects/apache/mod_svn_view/">mod_svn_view</a>,
                    <a href="http://www.horde.org/chora/">Chora</a>,
                    <a href="http://www.edgewall.com/trac/">Trac</a>,
                    <a href="http://web-cpan.berlios.de/modules/SVN-RaWeb-Light/">SVN::RaWeb::Light</a>,
                    <a href="http://www.polarion.org/svnbrowser.php">SVN
                        Browser</a>,
                    <a href="http://insurrection.tigris.org/">Insurrection</a>
                    and <a href="http://www.osdevel.org/projects/show/16?lang=en">perl_svn</a>.
                    Aside
                    from that, the Subversion Apache service provides a
                    rudimentary web-interface.
                    </s>
                <s id="cmplus">
                    Yes.  Can be configured to restrict which operations
                    are allowed by which users, so that customers may access their
                    requests without seeing development team data.
                </s>
                <s id="superversion">No.</s>
                <s id="svk">Yes. Same as Subversion.</s>
                <s id="arch">
                    There's <a href="http://arch.bluegate.org/viewarch.html">ViewARCH</a>, and
                    <a href="http://migo.sixbit.org/software/archzoom/">ArchZoom</a>
                    which are
                    works in progress.
                </s>
                <s id="bazaar">
                    Yes, several:
                    <a href="http://www.lag.net/loggerhead/">Loggerhead</a>,
                    <a href="http://goffredo-baroncelli.homelinux.net/bazaar/">Webserve</a>,
                    <a href="http://mccormick.cx/dev/bzrweb/index.py/log/bzrweb/head">Bzrweb</a>,
                    and
                    <a href="http://bazaar-vcs.org/TracBzr">Trac</a>.
                </s>
                <s id="darcs">
                    <a href="http://abridgegame.org/cgi-bin/darcs.cgi/darcs/">darcs.cgi</a>
                    is included in the distribution.
                </s>
                <s id="aegis">Yes.</s>
                <s id="mercurial">Yes.  The web interface is a bundled component.</s>
                <s id="monotone">No.</s>
                <s id="opencm">No.</s>
                <s id="perforce">Yes, P4Web.</s>
                <s id="purecm">Yes.</s>
                <s id="vesta">
                    Yes: <a href="http://www.scooter.cx/vestaweb/">Vestaweb</a>.
                </s>
                <s id="co-op">Since this functionality is always
                    available locally, there is no need for web interface.
                </s>
                <s id="vss">
                    It is possible to code one using the API, but no official
                    or third-party one exists.
                </s>
                <s id="cmsynergy">Possibly.</s>
                <s id="clearcase">
                  Yes. Web views are supported.
                </s>
                <s id="ls-sync">
                  Yes, without diff features but with a better awareness support.
                  (allow to know at any time on each version each one is working on)
                </s>
                <s id="SourceAnywhere">Currently not.</s>
                <s id="git">
                    Yes.  Gitweb is included in distribution.
                </s>
                <s id="tfs">Web Access is available as download for free.</s>
            </compare>
        </section>
        <section id="availability_of_guis">
            <title>Availability of Graphical User-Interfaces.</title>
            <expl>
                What is the availability of graphical user-interfaces for
                the system? How many GUI clients are present for it?
            </expl>
            <compare>
                <s id="cvs">Very good. There are many available GUIs:
                    WinCVS, Cervisia (for KDE),
                    TortoiseCVS (Windows Explorer plug-in).
                </s>
                <s id="accurev">
                    A single, comprehensive,
                    java-based GUI is provided.  The GUI has the same
                    look-and-feel on all platforms.
                </s>
                <s id="bitkeeper">
                    Good. BitKeeper ships with several
                    GUIs for performing common tasks. I'm not aware
                    of any third-part GUIs.
                </s>
                <s id="subversion">
                    Very good. There are many available
                    GUIs: RapidSVN (cross-platform),
                    TortoiseSVN (Windows Explorer plug-in), Jsvn (Java), etc.
                    Most of them are still under development.
                </s>
                <s id="cmplus">
                    Excellent.  Windows and Unix/Linux GUI as well
                    as web GUI.  Extensively configurable via simple menu files,
                    browser files, etc.  Can customize the set of to-do lists by
                    user/role, same for menus, pop-up menus, default visible tabbed
                    reports, etc.  GUI also used for all admin and for process
                    and data schema customization.  Also plug-in for Visual Studio,
                    Eclipse, etc. and File Browser (Windows).
                </s>
                <s id="superversion">
                    A GUI is integrated.
                </s>
                <s id="svk">
                    No GUIs are available.
                </s>
                <s id="arch">
                    There are
                    <a href="http://www.ibe.miee.ru/tlator/">tlator</a>,
                    <a href="http://www.hpl.hp.com/personal/Yasushi_Saito/octopy/">Octopy</a>,
                    and <a href="http://www.nongnu.org/archway/">ArchWay</a>
                    and possibly others under development.
                </s>
                <s id="bazaar">
                    There are several graphical frontends in
                    development,
                    see <a href="http://bazaar-vcs.org/BzrPlugins">the Bazaar Plugins page</a>
                    and <a href="http://bazaar-vcs.org/3rdPartyTools">the Third-party Tools page</a>.
                    Notable
                    are <a href="http://bazaar-vcs.org/QBzr">QBzr
                    (Qt)</a> and
                    <a href="http://bazaar-vcs.org/bzr-gtk">bzr-gtk (GTK+)</a>, which
                    can be considered beta quality.  Work is also
                    being done on integrating Bazaar with Windows
                    Explorer, Eclipse, Nautilus, and Meld.
                </s>
                <s id="darcs">
                    None to speak of.  (There is a modest graphical
                    interface to a few commands in the distribution, but it
                    is not being developed currently.)
                </s>
                <s id="aegis">
                    There is tkaegis.
                </s>
                <s id="mercurial">
                    History viewing available with hgit extension;
                    check-in extension (hgct) makes committing easier.
                    Some third-party IDEs and GUI tools (e.g. eric3,
                    meld) have integrated Mercurial support.
                </s>
                <s id="monotone">
                    No GUIs are available.
                </s>
                <s id="opencm">
                    No GUIs are available.
                </s>
                <s id="perforce">
                    Yes, P4Win and others based on the available libp4
                    library.
                </s>
                <s id="purecm">
                    Cross-platform GUI for Windows, Linux, Mac OS X
                    and other UNIXes.
                </s>
                <s id="vesta">
                    No GUIs are available, but the repository has a
                    C++ API, and it is not hard to write one.  (At
                    least three different project-specific ones have
                    been written by users at Compaq and Intel.)
                </s>
                <s id="co-op">The system is GUI-based by design.</s>
                <s id="vss">
                    Standalone GUI comes with it, plus SCCI plug-in for
                    MS Visual Developer Studio. There is an Eclipse
                    plug-in.
                </s>
                <s id="cmsynergy">
                    A couple of GUIs.  A motif-based one
                    (even on Windows) allows most functionality but is clunky.
                    A nicer Java one allows developer work but not much
                    administrative stuff. Has an SCCI plug-in, though it
                    doesn't handle network problems well.
                </s>
                <s id="clearcase">
                  Supplied for both Windows and UNIX. GUI tools are
                  typically not as solid as the command-line tools
                  though.
                </s>
                <s id="ls-sync">
                  One written in Java/SWING and available on any OS that
                  is automatically launched from the repository web page and
                  another one which is an Eclipse plugin.
                </s>
                <s id="SourceAnywhere">The system is GUI-based by design.</s>
                <s id="git">
                    Gitk is included in distribution.  Qgit and Git-gui tools are also available.
                </s>
                <s id="tfs">TFS client integrates into Visual Studio.</s>
           </compare>
        </section>
    </section>
    <section id="license">
        <title>License</title>
        <expl>
            What are the licensing terms for the software?
        </expl>
        <compare>
            <s id="cvs">GNU GPL (open source)</s>
            <s id="accurev">Proprietary, named-user licensing.</s>
            <s id="arch">GNU GPL (open source)</s>
            <s id="bazaar">GNU GPL (open source)</s>
            <s id="darcs">GNU GPL (open source)</s>
            <s id="bitkeeper">
                Proprietary, binary only license. Pay per use license,
                with an option for a costless license for developers of
                open-source software. Used to have a gratis, downloadable
                license, which was intended for the develpoment of open
                source software. It had <a href="bk-license.html">a
                    problematic license</a>,
                and was discontinued starting at April 2005.
            </s>
            <s id="aegis">
                GNU GPL (open source)
            </s>
            <s id="subversion">
                Apache/BSD-style license. (open-source)
            </s>
            <s id="cmplus"> Network licenses and user licenses. No minimum
                checkout time, and automatic license checkin on idle. License
                server included in product. Professional and Enterprise editions.
                Enterprise includes customizations, additional applications, and
                full multiple site capability.  One Server license per site. Total
                license cost per user typically less than $1000 + 18% annual mtce.
            </s>
            <s id="superversion">
                GNU GPL (open-source)
            </s>
            <s id="svk">Perl License. (open source)</s>
            <s id="mercurial">GNU GPL (open source)</s>
            <s id="monotone">GNU GPL (open source)</s>
            <s id="opencm">
                GNU GPL (open source), but moving soon to
                BSD or CPL (also open source).
            </s>
            <s id="perforce">
                A proprietary, binary only, commercial license.
                <a href="http://perforce.com/perforce/price.html">Price
                    starting at $800 per seat for the first year</a> and then
                a $160 for continuing support for the subsequent years. The
                latter payment is optional and required only for support,
                as the product can be used without it. Free for
                Open Source projects (no support in this case).
            </s>
            <s id="purecm">
                A proprietary, binary only, commercial license.
                <a href="http://www.purecm.com/purchase">Price
                    starting at $1000 for 5 users</a>
            </s>
            <s id="vesta">
                GNU LGPL (open source)
            </s>
            <s id="co-op">Proprietary, short text key. 30-day
                full-featured trial. Free to "observers"
                (members who don't make changes).
                $159 per workstation.
            </s>
            <s id="vss">
                VSS Ships with MSDN, and can also be purchased
                standalone or with other tools.
            </s>
            <s id="cmsynergy">
                Prices negotiable with salesman.
                Server is typically roughly 20,000 British Pounds.
                Clients are 4,000 British Pounds.  Per-year costs of 18%
                of original.
            </s>
            <s id="clearcase">
              Proprietary, with floating license supported. License
              server contacted for each clearcase operation, which
              obtains a license to be used for the next 30-60
              mins. Prices are several $k per license plus yearly
              maintenance fee. Typically 1-3 users per license
              required, depending on activity. Multisite requires
              additional licensing.
            </s>
            <s id="ls-sync">QPL - The Qt Public License (OpenSource)</s>
            <s id="SourceAnywhere">Proprietary, named-user licensing.</s>
            <s id="git">GNU GPL v2 (open source).</s>
            <s id="tfs">Commercial license.</s>
        </compare>
    </section>
</section>
    </contents>
</comparison>
