ZyXEL Communications X6004 User Manual page 356

Chapter 23 ZyStack
Master/Slave in ZyStack
When you create a ZyStack, the X6004s can take on a role of a master or a slave.
There can only be one master X6004 per ZyStack. You can manage the
configuration of the master and slave X6004s by logging into the LAN or WAN IP
address of the master X6004.
ZyStack Internal Call Routing
When an IP phone is a SIP client of one X6004 (A in the figure) and it calls a
telephone that is a SIP client of another X6004 (B in the figure). The default
behavior of the X6004 (A) is to process the call and connect it to the X6004 (B) on
which the SIP client is configured. This telephone call is illustrated by the solid line
in the following figure. Note that the processing resources of both X6004s are
being utilized throughout the duration of the call.
The X6004s can handle internal calls more efficiently if you specify the local
subnets which can connect to other ZyStack members. The dotted line shows the
same phone call after it has been redirected to X6004 B. In this scenario the
subnet 192.168.1.0/24 was configured as a local subnet. When A receives a call
from a SIP client that matches the local subnet and the destination of the client's
request is a phone connected to another X6004 (B), it then redirects the call to B.
Figure 214 Internal Call Routing
192.168.1.1
192.168.1.2
A
B
192.168.1.102
192.168.1.101
In this first example all the devices reside on the same subnet. A single subnet
configuration is recommended for ease of use and management. This, however, is
not always possible in your network.
The following example shows an example where your IP phones are located in
different subnets on your network. The X6004s are still on the same subnet
(Subnet 1). IP phones in Subnet 2 and Subnet 3 are both SIP clients of X6004
A. In this example, Subnet 3 has been configured as a local subnet. When X6004
A receives a call from a phone on Subnet 3 that is directed to a SIP client of
X6004 B, it is then able to redirect the call directly to X6004 B. Subnet 2,
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X6004 User's Guide