Kraun KR.XY, User Manual

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Voice protocol software
A choice of two different Voice protocols can be used to establish, maintain and terminate Voice
calls over the IP network. The following protocols are supported:
• SIP (Session Initiation Protocol). See RFC 3261.
SIP uses a peer-to-peer model, which has several advantages, including scalability. With SIP
the call control is performed in the devices that terminate the call, not in some central Call Agent.
The control of the call is performed directly between the two ends of the call. There can be
intermediate nodes, which are used in call establishment, these are known as proxies (or proxy
servers). The use of proxies in the network is not mandatory but has advantages for modularity
and scalability.
SIP features
SIP stands for Session Initiation Protocol (SIP), an application-layer control (signalling) protocol
for creating, modifying, and terminating sessions with one or more participants.
These sessions can include Internet telephone calls, multimedia distribution, and multimedia
conferences.
SIP invitations carry session descriptions that allow participants to agree on a set of compatible
media types. SIP makes use of network elements called proxy servers to help route requests
to the user’s current location, authenticate and authorize users for services, implement provider
call-routing policies, and provide features to users. SIP also provides a registration function that
allows users to upload their current locations for use by proxy servers. SIP can be configured
to run on top of several different transport protocols such as TCP or UDP. When a call is set up
using SIP, the two SIP agents use RTP (Real-time Transport Protocol, RFC 3550) packets to
send voice samples to each other directly.
Caller ID region support
Caller ID Region support enables both Type 1 and Type 2 Caller ID to be supported for various
regions of the world. Type 1 Caller ID is the variant of Caller ID used if the phone is on-hook.
Type 2 Caller ID is the variant of Caller ID used to interrupt an existing call (i.e. when the phone
is off-hook).
The following table defines the current IAD VoIP Caller ID behavior for different call scenarios:
Table 3-3: Call scenarios for Caller ID support
Type of call in
progress
Type of
incoming call
Caller ID
required
Action
None (On-hook) VoIP Type 1 Generate Type 1 Caller ID.
VoIP (Off-hook) VoIP Type 2 Generate Type 2 Caller ID.