Messaging - Nortel 1000 Description, Installation And Operation Manual

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.
System description
IP Trunk Description, Installation, and Operation
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