R&S M3SR 4100 Series, Operating Manual

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Operating Manual 6175.4760.02 – 01 5.111
M3SR Series 4100 Voice over IP (VoIP)
Call Initiation
An operator at any radio in the radio network is able to initiate a call. A phone book entry can
be chosen remotely (GB2PP) or from the MMI. It is also possible to dial the SIP phone num-
ber of the desired called party from the MMI. This request is sent to the VoIP gateway radio,
which tries to initiate a call session with the desired called party through SIP.
When an external VoIP user wants to call the radio network, it calls the VoIP gateway radio.
To address a particula radio in the radio nework, the Name of the Radio (RGA, ALE-3G) in
the network is called. The VoIP gateway radio is able to accept an incoming call automati-
cally after a period of time defined by means of the automatic call accept delay parameter
configured for the VoIP gateway radio via the R&S RNMS3000 (the default value is 10 s).
However, in case the automatic response is not desired, this parameter should be set to
65535 s to deactivate it. This ensures that the incoming call can only be answered by an op-
erator of a radio in the radio network.
For SECOM-V, if the radio network is called, the VoIP gateway radio broadcasts a signalling
message announcing the incoming call to the endpoint radios. Operators are able to accept
this call before the timeout defined by the automatic call accept delay. Calls can be accepted
on any radio. Since ALE-3G uses the standard xDL for IPoA services which does not support
broadcast, only the remote radio can accept an incoming call (either automatically or manu-
ally).
Call Termination
Any radio operator in the radio network is able to terminate incoming or outgoing calls to or
from his radio if the phone service is enabled. The call session can also be terminated by the
external VoIP user.
The limitation of the phone service for ALE-3G affects only the broadcast of signalling
messages from the VoIP gateway to the endpoint radios. Therefore the announcement
of an incoming call to the endpoint radios in broadcast mode is not supported. The
initiation and termination of a call from an endpoint radio is, nevertheless, not affected
by this limitation.
5.5.1.5 Scenario: Call Session between a Radio Network and a VoIP Telephone
This scenario describes a VoIP communication over an IP network between a radio network
and a VoIP telephone.