User guide

Connections 153
PBX Networking
Connections
Networking two or more TK systems means interconnecting them.
The Forum 523/524 allows you to use the following connections:
z ISDN trunk lines
z ISDN point-to-point connections (Q.SIG) on external S
0
ports
z IP network connections (Q.SIG-IP or SIP tie line)
Note: Networking via IP network connections requires a MGW
interface card Forum 525 Media Gateway Card.
Example of a PBX network
Various line types and transmission protocols can be used for
point-to-point connections. The required network topology (dis-
tance, connection capacity) determines which type of point-to-
point connection is most suitable.
An IP network connection with Q.SIG-IP or SIP tie line can be
established either with a direct LAN connection or via a fast VPN
connection (see also Branch Link starting on page 97). When the
connection is via internet, encryption is advisable for security rea-
sons.
Point-to-point
connection
Trunk line
PBX PBX PBXPBX
PBX