Page 390 of 910 Configuration of IP Telephony nodes using Element Manager
553-3001-365 Standard 4.00 August 2005
Figure 93
Routes
Under Routes, enter the IP address and Subnet mask for any host that
is not on the ELAN subnet but requires access to the Voice Gateway
Media Card across the ELAN subnet. A Telnet session for maintenance
from a remote PC is an example of when this would be needed. The
address of the remote PC would be added in the Route list.
The default route on the card causes packets destined for unknown
subnets to be sent out on the TLAN network interface. Packets from an
external host arrive on the ELAN network interface and responses are
sent on the TLAN network interface. This process can cause one-way
communication if the TLAN subnet is not routed to the ELAN subnet. It is
necessary to add an entry in the Route list to correct the routing so that
response packets are sent on the ELAN subnet. Each entry creates a
route entry in the card's route table that directs packets out the ELAN
network interface. See Figure 94 on page 391.
CAUTION
Use caution when assigning card routing table entries.
Do not include the IP address of an IP Phone. Otherwise,
voice traffic to these IP Phones is incorrectly routed
through the ELAN subnet and ELAN subnet gateway. To
avoid including the wrong IP address, Nortel
recommends that Host IDs are defined for the card
routing table entries.