IPv6 Network Programming

62 5.2 Further Extensions

5.2

5.3

Now, we need to make a couple of design decisions:

• Whether to listen to multiple sockets and use poll(2)/select(2), or listen to a

single socket and run multiple instances of popa3d

• What we should do about sessions[].addr

Here, we made the following decisions:

• Make popa3d listen to a single socket only, and switch the address family using

a command-line argument: -4 or -6.

• Use string representation of the address for session[].addr. The member is used

to rate-limit access from the same address; therefore, the format (binary or

string) does not matter if we can uniquely identify the peer. ...