[asterisk-users] t1 cards

[Gordon Henderson]

On Thu, 2 Oct 2008, Eric Fort wrote:

> I presently need to connect a few channels of voice and data between
> multiple locations where I own the copper between them.  Each location
> exceeds 300M from any other location.  I'm thinking of generating T1's and
> running those between locations.  If I use PC based cards wired back to back
> (I can do that, right?) what kind of distance can I expect to be able to
> span without needing repeaters?  What inexpensive cards can you recommend
> for use with asterisk?  I'm considering either digium or sangoma.  Would I
> get any better performance if I used a sync-serial card connected to a
> separate csu/dsu?

300 metres, right? (not 300 miles?)

Why stop at T1? Go for E1 :) with the right kit at each end you ought to 
be able to get 2Mb/sec or more. (distance depending)

Personally, I'd go for a technology that gave me Ethernet at each end - 
then it makes it much easier to mix voice and data - But using something 
like a sync. modem and line driver then you need a media converter of some 
sorts at each end which might bump up the cost - at the savings of the E1 
card in the PC though. Last time I had bare copper to play with (a BT EPS8 
circuit) I had a 2Mb modem at each end going into a Cisco 2600 which was 
running CHDLC over the link and acting as nothing more than a dumb media 
converter to give me Ethernet at each end. This was 6 years ago though.

Ah, Looks like the technology has improved somewhat:

   http://www.blackbox.com/Catalog/Detail.aspx?cid=381,1452,1468&mid=5261

From the UK site:

Or even:

   http://www.blackbox.com/Catalog/Detail.aspx?cid=425,1423,1424&mid=4946

(same thing from the UK site:)

   http://www.blackbox.co.uk/solutions/display.asp?cs=dvh&id=1&doc=lb300a-r2&tx=LAN&sx=Network%20Appliances

You need a pair, obviously...

Hm. US site is $305, UK £253. Rip-off Britain again by the looks of it....

As for inexpensive cards - OpenVox. Their E1 cards seem to work OK, but 
if using a LAN extender, then they're not neeed at all...

Gordon