WCF Sessions vs ASP.Net Sessions

WCF sessions are different from ASP.Net sessions

• ASP.NET sessions are always server-initiated.(WCF session is caller initated)
• ASP.NET sessions are implicitly unordered(WCF session is processed in the order of reception)
• ASP.NET sessions provide a general data storage mechanism across requests(not in WCF session except 'durable services')

In ASP.Net you can access session very easily

1) In config: <configuration>
<sessionstate
mode="inproc" />
1) and then in code : Session("Stocks") = "MSFT; VRSN; GE"

But in WCF, to manage sessions, we should learn about a few WCF concepts:
1) There is an attribute to enable session(SessionMode)
2) We should manage instancing ourselves (which is there for an entirely different purpose)
3) Instancing is related to binding, so we should learn about supporting bindings
4) We might even need to control the execution threads(concurreny)
For simple and indepth overview on WCF Sessions check this blog