Redirect External Links
A strategy for dealing with PageRank spam on wiki. All external links are forwarded to a simple redirect script. Google runs a public redirect script for this purpose.
Additional information:
- http://simon.incutio.com/archive/2004/05/11/approved
- http://www.theregister.co.uk/2005/01/19/google_nogoogle/
Advantages:
- You can keep your wiki open to edits from anyone, and know even if you do get spam you aren't helping their PageRank.
Drawbacks:
- Eliminates PageRank for non-spam links, too.
- Doesn't really deter people from adding WikiSpam. Might become more of a deterrent once WikiEngines start adopting this strategy. Currently, none do - only some blog engines like MovableType.
See NoFollow. This new link tag also will stop Google from adding PageRank to the link. It is probably better than having to completely redirect the link.