Nortel Meridian Meridian 1 Feature Description And Administration page 1195

Figure 95
Transit node RRA operation
Node A
MCDN
MCDN Alternate Routing examples
SBOC = RRA
Node B
Call is routed to next
available alternate route.
Example 1: Meridian 1 networked with Passport
In this scenario (refer to Figure 96), node A attempts to call node B using a
primary route through Passport. The primary route is congested. Passport
sends the cause value in the Call Clearing message to node A. With node A
defined as SBOC = RRA or RRO, the cause value triggers a retry to make the
call through the next alternate route. Alternate route 1 is from node A to node
B through nodes C and D. If alternate route 1 is unavailable, then an attempt
is made to route the call through alternate route 2: node A to node B through
the Public Network.
International ISDN PRI Feature description and administration
MCDN Alternate Routing
SBOC = RRA or
RRO or NRR
Node C
MCDN
Call Clearing
message
Node E
Private
Exchange
or
C e n t r a l
O f f ic e
Page 1195 of 1814
Node D
Congestion
Call is established
using alternate route.
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