[Asterisk-biz] PRI Hardware Echo Canceller

[alex at pilosoft.com]

On Thu, 30 Jun 2005 ewr at erols.com wrote:

> >> Unfortunately, soldering a power supply and cat 5 on to a 20 year old
> >> card from ebay and then putting it all in a shoe box, or trying to track
> >> down (as the wiki calls them) "the highly desireable 2 slot 253C"
> >> shelves, are not really the greatest options for a corporate
> >> environment.
> > ebay usually has those shelves, not the 2-slot ones, but 7-slot older
> > ones. yeah, they are wirewrap, big deal.
> 
> Is that the 253B shelf?  Wire-wrap is not really the problem.  The real 
> problem is availability (though size is also a consideration).  I just 
> looked through the Tellabs equipment on ebay and don't see any of the 8-slot 
> shelves available right now.
> 
> Either way, it doesn't solve my problem.  If I am installing asterisk in
> a small to medium sized office, I would like to find a product that is
> easy to purchase and easy to connect.  I don't want to rely on something
> that I *might* be able to get if I watch ebay close enough, never
> knowing just how much space it needs, how much I will have to pay for
> it, or if it will actually work when it arrives.
Yes, indeed, I don't disagree. In this case, you should hire Steve 
Underwood to write a proper g.168 echocanceller ;)

In my case, all T1s from remote offices are backhauled to central pop 
where I do echocan.

> I didn't really mean to be short in the last email, but it seems (IMHO)
> that there is a huge need for a current product like this.  Evidently
> they *do* exist, at least according to the Ditech and Valient websites,
> but I can't seem to find anyone that actually sells them.  My hope was
> that some of the other integrators or suppliers on this list might have
> found a current product that fills this need.  Is everyone just using
> the ancient Tellabs stuff?
Thing is, all existing devices are very-high-density and nobody seems to 
be interested in doing single-span echocan. I think latest tellabs stuff 
cancels a DS3 at a time. ;)