[asterisk-users] One PRI card with 2 (or more) Telcos

[Tiago Geada]

Hi Kevin,

Thanks for your elaborated answer. I will try and set them on the same clock
and see if no problem occurs. If so, Different telco's clocks would be in
SYNC (I do doubt it).

This machine has no more PCI slots available and hardware is damn expensive.

Will have to look into it with my boss..

Thanks you.

On 18 March 2011 18:30, Kevin P. Fleming <kpfleming at digium.com> wrote:

> On 03/18/2011 01:23 PM, Tiago Geada wrote:
>
>> Hi! I can try that tho. Where do I configure what timer to use??!
>>
>
> If your telcos are not synchronizing their network clocks to each other,
> you will not be able to solve this problem on a multi-port Digium T1/E1
> card. Digium T1/E1 cards select a single master clock (either the onboard
> clock or the clock recovered from one of the spans) to use as the 'board
> clock', which is then used to transmit data on all the spans. If the master
> clock is not in synchronization with the clocks at the other end of those
> spans, then bit slips will occur and cause various sorts of problems. This
> is why a card is always configured to use the recovered clock from a telco
> span if there is one, because the onboard clock would never by in sync with
> it.
>
> If you have a board connected to two telcos and their clocks are not
> synchronized, not only will you have trouble using a Digium card, but even
> using a card that can handle using multiple transmit clocks at once will not
> solve the underlying bit slip problem that will occur if you ever connect a
> channel from Telco1 to a channel from Telco2. If you *never* connect
> channels between Telcos, then you don't have to worry about that problem,
> but if you do, at some point during the call there will be buffer overruns
> or underruns and there will be some effect (for a normal voice call, the
> effect might be a short audio artifact, and fairly harmless... unless the
> call is a modem or FAX call, in which case it could cause the call to fail).
>
> For your sanity, I would strongly suggest that you don't connect spans from
> multiple telcos/networks/etc. on a single card, but keep each span provider
> on their own card.
>
> --
> Kevin P. Fleming
> Digium, Inc. | Director of Software Technologies
> Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
> 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
> Check us out at www.digium.com & www.asterisk.org
>
>
> --
> _____________________________________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
> New to Asterisk? Join us for a live introductory webinar every Thurs:
>              http://www.asterisk.org/hello
>
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>  http://lists.digium.com/mailman/listinfo/asterisk-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20110318/5be0204b/attachment.htm>