ZyXEL Communications IP PBX X6004 - Manual (Page 146)

Chapter 6 Server
X6004 User’s Guide
146
The BRI interface card enables the X6004 to communicate with the following BRI
switches.
• 5ESS - AT&T basic rate switches
• MDS100
• NI1 - National ISDN-1 switches
• ENT3 - Euro-ISDN switches (UK and others)
• AUS - Australian TS013 switches
Q.SIG
Q.SIG is a protocol used for ISDN PRI voice signaling. Q.SIG enables the X6004 to
connect PBXs and central office switches (COs) using the Q.SIG protocol. The
X6004 can be a Q.SIG master or Q.SIG slave.
• Master - is responsible for layer 2 signaling and initiates the negotiation.
• Slave - responses master’s signaling.
You must connect a Q.SIG master device to a Q.SIG slave device. An example of a
Q.SIG configuration is shown next.
Figure 52 Q.SIG Configuration Example
Side A/B Settings in Q.SIG
When using Q.SIG, the side A and B settings are used to avoid voice channel
collision. See an example in the following figure. In E1, there are 30 voice
channels. X6004 (X) requests to use channel 1 for an outgoing call and waits for
Y’s response. Almost at the same time, X receives Y’s request to also use channel
1 for an outgoing call. If you configure X to use the side A, X will ignore Y’s
ISDN
Device
ISDN
Device
Q.SIG
T1/E1
Slave Master
Q.SIG