Re: CT1 vs. PRI

Marty Likier (marty@livingston.com)
Wed, 16 Apr 1997 07:45:30 -0700

At 08:45 AM 4/16/97 -0500, Jeffrey J. Mountin wrote:
>At 07:22 AM 4/15/97 -0700, Marty Likier wrote:
>>The real question is do require ISDN service? If you do, than PRI is the
>>best way to go. If you are just trying to support dial-in analog modems,
>>then CT1 is a good choice. However with that said, the PM3's has a unique
>>implementation for answering calls over a CT1 which permits the answering
>>of both analog modems and ISDN (56K) data-over-voice calls. So you can get
>>limited ISDN service without paying for the premium of PRI. ;-)
>
>But even if you use just the modems isn't PRI the preferred method?

This might be a religous issue, but I agree PRI is preferred for 3 main
reasons:
(1) PRI call setup time of 300 ms as opposed to T1 call setup time of 3-5 sec
(2) PRI uses out-of-band signaling which means a data channel isn't
allocated if the destination number is busy. T1 allocates a channel while
it checks to see if the destination line is busy.
(3) Total bandwith (PRI) 23 x 64K = 1472K, (T1) 24 x 56K = 1344K

>I believe this was brought up before and once K56flex is out I plan to have
>one PRI turned up and see if it does work better over PRI. Regardless the
>real world testing is what counts. 8-)

K56flex should work equally as good on T1s, but I agree real world testing
is what counts. ;-)

--
Marty Likier
Product Marketing Mgr.
marty@livingston.com