CANCEL and OPTIONS

CANCEL

In addition to canceling a pending session
CANCEL can also be sent by a proxy or user agent
- for example, when a parallel fork has been done, once you have a successful match, then you can cancel the others

OPTIONS

Used to query a server or user agent for its capabilities
sometimes used for very simple presence information

Transcript

[slide151] Therefore we needed the cancel functions. We also had the OPTIONS so we could say what kind of functionalities does the other party support.