Which two Sip requests use the same Cseq number of an earlier INVITE request? (Choose two.)
A. NOTIFY
B. UPDATE
C. REFER
D. BYE
E. ACK
F. CANCEL
Which two Sip requests use the same Cseq number of an earlier INVITE request?
Which two Sip requests use the same Cseq number of an earlier INVITE request? (Choose two.)
A. NOTIFY
B. UPDATE
C. REFER
D. BYE
E. ACK
F. CANCEL
E.F
Requests within a dialog MUST contain strictly monotonically
increasing and contiguous CSeq sequence numbers (increasing-by-one)
in each direction (excepting ACK and CANCEL of course, whose numbers
equal the requests being acknowledged or cancelled).
EF
https://tools.ietf.org/html/rfc3261#section-12.2.1.1
EF
EF according to RFC