Use the official manual to learn more about SubVersion. You can use SubVersion to checkout the software, choose either of the following options:

1. Check out the latest stable revision, including the most recent security and bug fixes:

On the logging server:

svn checkout http://svn.ids.surfnet.nl/surfids/logserver/tags/stable-2.00.04/ /tmp/opt/surfnetids

On the tunnel server:

svn checkout http://svn.ids.surfnet.nl/surfids/tunnel/tags/stable-2.00.04/ /tmp/opt/surfnetids

2. Check out the latest and greatest bleeding edge software with lots of cool new stuff, and cooperate in adding functionality and fixing bugs.

On the logging server:

svn checkout http://svn.ids.surfnet.nl/surfids/logserver/trunk /tmp/opt/surfnetids

On the tunnel server:

svn checkout http://svn.ids.surfnet.nl/surfids/tunnel/trunk /tmp/opt/surfnetids

3. Or check out the entire project to some local path:

svn checkout http://svn.ids.surfnet.nl/surfids /some/local/path

The bug fixes for each major release can be found in the branches for each part of the SURFids.

Tunnel server bugfixes
Logging server bugfixes

You can just check these files out and overwrite the old ones.

svn checkout http://svn.ids.surfnet.nl/surfids/tunnel/branch/bugfixes-2.00.04/ ./tunnel-bugfixes
svn checkout http://svn.ids.surfnet.nl/surfids/logserver/branch/bugfixes-2.00.04/ ./logserver-bugfixes