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hi Hans,<BR>
<BR>
The standard for a PABX on G.711 is 6ms packaging of data - this is 48 byte per channel. If you go higher than this you start getting to much latency, if you go lower than this you start using to much CPU.<BR>
<BR>
400 byte is 50ms, meaning we have spent a lot of the latency budget already here, but this shoud be run-time configurable per channel as per need.<BR>
<BR>
- G.711 6 ms<BR>
- IVR is 250 ms<BR>
- 729 10 ms<BR>
- 723 30 ms<BR>
<BR>
etc.<BR>
<BR>
You need to take into consideration that you are on a system with 8, 16 or 32 E1's of whick some is running IVR, others SIP, others swicthing back out on a different E1 etc.<BR>
<BR>
Jan<BR>
<BR>
> <BR>> Also I have thought through message timing. In bigger systems I see that it is <BR>> required to dither messages in time. On cannot simply receive 30x400 bytes on <BR>> an E1 and burst it into the system, because the message queues will overflow <BR>> pretty quickly. Instead the interrupt rate of the hardware needs to be <BR>> increased so that 400 bytes are received in "1/30 * interval" fashion. This <BR>> will generally improve the system and load-balance in time.<BR>> <BR>> <BR>> The generic Message Header looks like this:<BR>> <BR>> /* NOTE: All fields are little endian */<BR>> <BR>> struct zap_hdr {<BR>> uint8_t dwDstNode[4]; /* Destination Node */<BR>> uint8_t dwSrcNode[4]; /* Source Node */<BR>> uint8_t wCommand[2]; /* Command Number */<BR>> uint8_t wMsgNum[2]; /* Message Number */<BR>> uint8_t bReserved[4]; /* Reserved bytes */<BR>> };<BR>> <BR>> If you have access to ISDN testing equipment and would like to help test the <BR>> non-EuroISDN variants of my upcoming ISDN implementation, please let me know.<BR>> <BR>> I expect to have something up and running within the next month, hopefully not <BR>> running out of time this time :-)<BR>> <BR>> --HPS<BR>> <BR>> _______________________________________________<BR>> Freeswitch-dev mailing list<BR>> Freeswitch-dev@lists.freeswitch.org<BR>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-dev<BR>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-dev<BR>> http://www.freeswitch.org<BR><BR><br /><hr />Get news, entertainment and everything you care about at Live.com. <a href='http://www.live.com/getstarted.aspx ' target='_new'>Check it out!</a></body>
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