NEC SL1100, Сетевое руководство

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NEC SL1100 Issue 6.0
Networking Manual 9 - 45
freely with each other. When building the VPN tunnels, throughout the
network, they must be assigned as a fully meshed network. This means that
every network is allowed direct connection to each and every other network in
the topology. Network equipment limitations may sometimes restrict this
ability resulting in no voice path on VoIP calls between sites. When this
happens Peer-to-Peer must be disabled in the SL1100. The downside to
disabling Peer-to-Peer is using more DSPs and consumption of additional
bandwidth at the MAIN location.
The following diagram shows three sites connected together via VPN. This
network is not fully meshed due to the lack of a VPN tunnel between Sites B
and C.
With Peer-to-Peer enabled, the IP phones on site A can communicate with IP
phones on sites B and C. IP Phones on sites B and C cannot communicate
directly with each other though. The IP phone from site B can set up a call to
the IP phone at site C, but there is no speech path. Here are the steps in the
call scenario leading to the failed call.

Extension 120 goes off hook and dials ext 130.

An initial invite message is sent from 192.168.2.15 (ext 120) to
192.168.1.10 (VoIPDB).

192.168.1.10 (VoIPDB) forwards that message to 192.168.3.26 (ext
130).
Figure 9-24 NEC SL1100 Network Example No. 2
VoIPDB IP Address =