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During call set-up, a codec is selected automatically for voice transmission. 2N
®
supports the codecs included in the table above. The type of codec to
VoiceBlue MAX
be used depends on your VoIP network (individual devices) and your 2N
VoiceBlue
®
configuration.
is designed primarily for VoIP corporate
MAX
2N
VoiceBlue MAX
®
networks and tries to meet the opponent's codec requirements. If a codec is
requested that is incompatible with
, the call will be rejected.
2N
VoiceBlue MAX
®
The SIP and ITU-T H.323 recommended protocols are mostly used for connection
establishing, maintaining and cancelling.
uses the
(Session
2N
VoiceBlue MAX
®
SIP
Initiation Protocol) signalling.
Tip
In the case of separated direct connection of your SIP Proxy and 2N
®
, use the G.711 codec to achieve a high voice quality.
VoiceBlue MAX
SIP Components
The following components are involved in the SIP message exchange:
UAC (User Agent Client) – the terminal device client, which initiates SIP
signalling.
UAS (User Agent Server) – the terminal device server, which responds to SIP
signalling from the UAC.
UA (User Agent) – a SIP network terminal (SIP phones, gateways to other
networks, etc.), which contains the UAC and UAS.
Proxy server – receives connection requests from the UA and transfers them to
the next Proxy server if the given station is not under it administration.
Redirect server – receives connection requests, but, instead of sending them to
the called line, sends them back to the requesting device asking for where to
route the request.
Location server – receives registration requests from the UA and updates the
terminal database accordingly.
All the server components (Proxy, Redirect, Location) are mostly on one physical
device called Proxy server, which is responsible for keeping a client database and
connection establishing, maintaining and terminating, as well as call routing.
