Design a session manager

Do we have a spec standard for designing a session manager? IMO, these are what a session should process:

2. a unique id for each session should be assigned (session id);
3. should be able to maintain attributes in the form of pairs;
4. should be able to check the client's availability (for instance, the client exits);
5. should be able to destroy a session;
6. 开发者_Python百科anything more?

Do we have some good example of a session manager?