NEC SL1100, Networking Manual

Page: 101 / 292

NEC SL1100 Issue 6.0
Networking Manual 7 - 7
4.5 Supported CODEC
SIP Trunking can use the following CODECs.

G.729. Low bandwidth requirement, and is used on most Wide Area
Network links

VAD

VIF size 20ms~30ms

G.711 – High bandwidth requirement – usually used on Local Area
Networks.

G.722 – This CODEC is useful in fixed network, Voice over IP
applications, where the required bandwidth is typically not prohibitive.

G.726 – is an ITU-T ADPCM speech coded standard covering the
transmission of voice at rates of 16, 24, 32, and 40Kbps.

ILBC (Internet Low Bitrate CODEC) – Narrow band speech. ILBC
enables graceful speech quality degradation for lost frames, which
occurs in connection with lost or delayed IP packets
S
ECTION
5
S
UPPORTED
SIP T
RUNKING
F
UNCTIONS
The functions in this section are supported by NEC SL1100 SIP Trunking.
5.1 Address Resolution
If using any SIP Proxy Server, the NEC SL1100 always sends messages to an
external SIP server.
If not using any SIP Proxy Server, the NEC SL1100 uses the internal address
table (Program 10-23 : SIP System Interconnection Setup).
When a user creates an interconnection network with SIP trunks,
Program
10-29-14 : SIP Server Information Setup - SIP Carrier Choice
must be set to 0
(default).
5.2 Authentication Process
When using an external SIP Server provided by a carrier, an authentication
process is usually needed.
NEC SL1100 SIP trunks support HTTP digest authentication process (MD5).
This process is done on a Register process and Initial INVITE process.