Karel DS200, Техническое справочное и монтажное руководство

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DS Series PBX Technical Reference And Installation Guide
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VII.3.T. EX200 (MGW1) MEDIA GATEWAY MODULE
A Media Gateway means the connection between the IP ports of the system and the TDM
(analog and digital) ports of the system or conversion from TDM to IP and from IP to TDM.
When an analog extension calls an IP extension or vice verse, the speech is bridged by the
media gateway channels.
The EX200 (MGW1) module supports 16 channels however, the channels to be used are set
by a license. MGW1 module has echo canceller, jitter buffer control, and similar QoS
services and G711 and G729 codecs.
As explained above the MGW1 is designed to carry audio to the destination via RTP
packages addressed by the system software.
The hardware structure of the EX200 (MGW1) module is exactly the same as the EX200
(16VoIP/0) module. However, the software is different.
Connection to the EX200 (MGW1) card is made over the RJ45 Ethernet connection on the
front face of the card.
VII.3.U. EX200 (MGW2) ADVANCED MEDIA
GATEWAY MODULE
The EX200 (MGW2) card has the same usage as MGW1 card but with some more advanced
feature.
MGW2 card has two daughter card slots with SODIMM connectors. These slots are for
media gateway channel add on cards which incorporates Black-fin DSP chips for the
functionality of MGW channels.
Each media gateway channel add-on card has one Ethernet connection for each black-fin
chip and also has an interface to the PCM backbone of DS200 series system.
There are two types of media gateway channels on add-on card. One has a single black-fin
chip which provides 12 RTP channels / 6 sRTP channels. The other one has two chips and
provides 24 RTP / 12 sRTP channels. The RTP and sRTP channel numbers can be
configured as an appropriate combination of both.
Due to the DS200 backbone topology any interface card may have maximum 32 channels.
The MGW2 card can provide 32 RTP channels or a total of 32 RTP and sRTP channels.
Since MGW2 card can have more than 16 channels, it has to be installed in an even
numbered slot and the next slot must be kept empty.
The MGW2 card supports G711, G729, G723 and iLBC codes and T.38 fax transmission
protocol and sRTP secure voice transmission protocol. (Note: T.38 and G723 are not ready
yet)
Connections to the EX200 (MGW2) card are made over the RJ45 Ethernet connection on the
add-on cards.