T1 = N1 = C3
  
            /
  
  C1 -- S1 - S2 = C4
  
         /  \
  
        C2 - T2

-	Jabber XML Protocol
= Any other protocol
C1, C2	Jabber Clients
C3	Client on another IM Network
C4	Client using an alternate protocol to access the Jabber Server
S1	Jabber Server
T1	Transport, translating between the Jabber XML Protocol and the protocol used on another IM Network
T2	Transport providing other real-time data to Jabber, such as log notifications or headline news feeds
N1	Third-party IM Network