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Messaging – Nortel Networks NN43001-563 User Manual

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Per-call statistics support using RADIUS Client

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key for authenticating RADIUS records (the key is maintained between
the RADIUS client and the RADIUS server)

Data is configured at the IP Trunk 3.01 (and later) node level and is
distributed to all the IP trunk cards associated with the IP Trunk 3.01 (and
later) node.

Messaging

The RADIUS client sends two records to the network listener: one when
the call is answered and one at the end of the call. The messages are
sent by the Follower card which processes the voice call (not the DCHIP or
Leader if they are not handling the voice data). The RADIUS protocol uses
UDP for message exchange. The client sends a message to the listener
and waits for an acknowledgment. If no acknowledgment is received,
the client re-transmits the record using the standard exponential backoff
theme. The data is stored on the IP trunk card until an acknowledgment is
received. When an acknowledgment is received, the data is discarded. The
client stores a maximum of 100 records. This allows two Start and two
End records for each of the 24 or 32 ports (depending on whether it is an
ITG-Pentium 24-port trunk card or a Media Card 32-port trunk card).

Start record

The Start record is sent when the call is answered. It contains the following
fields:

Calling party number

Originating IP address and port

Called party number

Destination IP address and port (of the actual card handling the call, not
the remote Leader)

Call start time

Call duration (time from call initiation to call answer)

Codec used

Orig/Term call side indication

Snapshot of remote Gateway’s QoS at time of call connect

The calling and called numbers (with their corresponding IP addresses) are
just that, regardless of which end is doing the originating. So the Follower
card on the originating side generates a RADIUS record with its own IP
address as the originating IP address. The terminating Follower also
generates a RADIUS record with that far end’s IP address as the originating
IP address and its own IP address as the destination address.

Nortel Communication Server 1000

IP Trunk Fundamentals

NN43001-563

01.01

Standard

Release 5.0

30 May 2007

Copyright © 2007, Nortel Networks

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