Subversion allows you to use SSH as the network protocol by using the svn+ssh:// scheme in the repository URL. One downside to this is that the only way to specify your remote username is in the URL, for example:

svn+ssh://dribin@svn.example.com/repo

This is all fine and dandy if you’re just doing a checkout, but this can cause problems if you want to use the svn:externals property. If you include a username in your URL, no other user can use the external without your remote password. Ideally, you want to allow each user to use their own username in the URL. Unfortunately Subversion has no way to override the SSH username in the URL. The trick around this is to not use usernames in URLs at all:

svn+ssh://svn.example.com/repo

You can then specify your remote username in your $HOME/.ssh/config:

Host svn.example.com
        User dribin