User guide

T1 Phonebook Configuration MultiVOIP User Guide
286
PhoneBook Configuration Parameter Definitions
(cont’d)
Field Name Values Description
H.323 Version 4 Parameters
Q.931
Multiplexing
(Mux)
Y/N Signaling for multiple phone calls
can be carried on a single port
rather than opening a separate
signaling port for each call. This
conserves bandwidth resources.
H.245
Tunneling (Tun)
Values: Y/N
Description: H.245 messages are encapsulated
within the Q.931 call-signaling channel. Among
other things, the H.245 messages let the two
endpoints tell each other what their technical
capabilities are and determine who, during the
call, will be the client and who the server.
Tunneling is the process of transmitting these
H.245 messages through the Q.931 channel. The
same TCP/IP socket (or logical port) already being
used for the Call Signaling Channel is then also
used by the H.245 Control Channel. This
encapsulation reduces the number of logical ports
(sockets) needed and reduces call setup time.