Filter
Top Products
Configuring general CS settings 343
SmartWare Software Configuration Guide 31 • CS context overview
Note Be careful when choosing where you get your clock source, if the clock used
for packaging the ISDN voice frames is not synchronized with the remote
ISDN clock, bit errors may result (such synchronization problems would
probably cause a fax transmission to fail).
• Two BRI ports will be needed, the first port for the ISDN phone and the second for the public ISDN net-
work (see section “Configuring ISDN ports” on page 348).
• Two ISDN interfaces will be needed, each bound to a BRI port (see section “Configuring call routing” on
page 345)
• An H.323 interface is required in order to use H.323 (see section “Configuring call routing” on page 345)
• The call router routing tables, and the H.323 and ISDN interfaces will have to be configure to support call
routing (see section “Configuring call routing” on page 345).
Calls are routed from an ISDN phone with a number in the range of 1xx–5xx to the main office with a fall-
back to the PSTN. All other calls are routed from the ISDN phone to the PSTN and from the PSTN or
main office to the ISDN phone.
• The H.323 gateway must be configured to use the G.711 codec (see section “Configuring an H.323 VoIP
connection” on page 348)
• Two Ethernet ports and their corresponding IP interfaces will be needed.
You must not start to configure the CS context and its components until you have finished planning your voice
environment. The following chapters explain how to convert the planned voice environment into the Smart-
Ware CS configuration. The IP configuration is not a topic in this example. For more information on IP con-
figuration refer to chapter 9, “IP context overview” on page 114.
Configuring general CS settings
There are several parameters that cannot be collected into one specific configuration task, because they are
independent of the rest of the CS context configuration and apply mostly to an interface card or even to the
entire SmartNode.
Configuring the clock source
A reference clock is needed for packaging the ISDN voice frames. The reference clock can be generated inter-
nally or obtained from an external source (e.g. public ISDN). SmartNode devices have a feature called ‘Clock
Source Hunting’. This feature allows to configure an index-based list of clock sources. The source with the low-
est index has the highest priority and vice versa. On SmartNode devices populated with several PRI or BRI
ports where more than one port is working in ‘clock slave’ mode, all these ports can be entered in the clock
source list. The algorithm behind this feature always takes the first synchronized ‘slave’ port in the list as the
current clock source. If the links of all the ports in the list are down or not synchronized, the system is falling
back to its internal clock source. It is also possible to enter all PRI or BRI ports of the device in the list, inde-
pendent on their clock mode. The Clock Source Hunting algorithm ignores all entered ports that are not
working in ‘slave’ mode.