Which port numbers to use/avoid for web services (WCF + Rest?)

Question

I'm looking to deploy a WCF services project to IIS - the services are both wsHttp and webHttp (not that it makes much difference!) in the same project at the moment.

The server is already hosting MVC3 web sites on port 80, separate to the web services.
In the future, the services and sites may be separated...depending on load/performance/cost etc.

Are there "accepted/common" ports or port ranges to use for web services?

Any ranges to really avoid (*obvious ports ignored of course - 25/80/8080/443/1521/etc.)

Answer 1

If you're expecting your app to get used by folks in all sorts of environments, I'd strongly encourage you to figure out how to host it on port 80. Everything else is going to get blocked by one sort of firewall or another. About the only port that just about every company allows open is port 80.

My personal experience with this comes from having hosted a Silverlight-accessible web service on a non-standard port (port 4502, though it doesn't make much difference). Because of Silverlight's networking limitations we didn't have much of a choice, but we ran into a whole bunch of firewall issues at one company after another after another. Do yourself a favor and just host it on port 80.