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DEFINITY ECS Release 8.2 ATM Installation, | Issue 1 |
Upgrades, and Administration | April 2000 |
6 Troubleshooting |
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Troubleshooting | |
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Are talk paths being established between port networks? |
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Diagnostics.
■Can you talk both ways on a set on one port network dialed from another port network and vice versa?
—The CBR (Constant Bit Rate) virtual circuits (VCs) between ATM switch PPN port and ATM switch EPN port are used for talk paths between port networks (PPN to EPN, EPN to PPN, or EPN to EPN).
—They are established when calls are first setup between port networks. Each virtual circuit represents one party of a complete multiparty talk path.
—These virtual circuits may persist beyond the duration of a phone call. The DEFINITY Call Processing software saves virtual circuits for a few seconds after the end stations have hung up in case the VC can be used again for another call between the same two port networks. Also, check
—There may be other CBR virtual circuits between ATM switch ports that are not associated with DEFINITY port networks. A common CBR application is Circuit Emulation, in which
Unusual ATM trouble conditions
A few failure modes in the DEFINITY ECS/ATM switch combination are particularly difficult to diagnose. One example might be that you cannot make a completely successful call even though most indications from DEFINITY ECS and the ATM switch look good.
This section documents some hints and clues that may help diagnose the following failure modes:
■Incorrectly typed or omitted EPN route or end system identifier (ATM switch)
■Swapped routes, end system identifiers, or fiber between a PPN and an
EPN
■Swapped routes, end system identifiers, or fiber between A- and
■Swapped routes, end system identifiers, or fiber between two EPNs