[Asterisk-Users] T1 Sync clarification

[John Todd]

At 9:17 PM +0800 1/14/04, Steve Underwood wrote:
>>[snip]
>>It's the same in the US, however in the US there are far more independent
>>telcos (example, Iowa had the distinction of the most independent 
>>telcos at 600+ of all states) and many of those do not have an 
>>engineering staff nor the expertise to address this. Their 
>>engineering is typically farmed out to either the central office 
>>switch vendor or to independent engineering firm(s) when needed. 
>>Those groups should have addressed it, but in at least some cases 
>>it was not.
>>The US also has some carriers that got into the national and/or international
>>long distance business with a low budget staff that ran hard but never
>>documented anything. (I've done some consulting work for two of those and
>>wouldn't bet a dollar on their attention to detail.)
>>
>>Rich
>>
>If they have frame slips too often FAX will not work. It would be 
>hard for even the most incompetant telco to ignore that. However, 
>their core equipment is likely to use a rhubidium clock and keep 
>everything OK, even if they done sync to their peers properly.
>
>Regards,
>Steve

This is getting pretty far off the topic of Asterisk, but I'll 
confirm that several of the small CLECS that I've worked 
for/consulted for do _not_ have their own timing sources in the form 
of a rubidium standard.  These also are carriers that sell PRI's and 
T1 connections out of their switching equipment.  They typically use 
clocking source from one of their interconnect providers, or they 
simply don't know the answer to the question of "who provides clock 
in your network?"

If they're taking sync off one of their upstreams, this is not so 
bad.  If they simply don't know where they're getting sync, this is 
much worse.  If my experiences have been this poor in what I think 
are fairly dense population/financially wealthy areas, I can only 
imagine what it's like as one moves further away from "high-budget" 
telephony centers.  A scrupulous tech will fix those problems... but 
there are a dwindling number of scrupulous techs, and an even shorter 
supply of money for rubidium standards or cesium beam timepieces.

In other words: I suspect a great number of Asterisk users, being 
(sometimes) budget conscious,  will run across these types of shady 
clocking situations since the lowest budget carriers often don't have 
the funding to implement the "right" solutions.

JT