Re: Please help - Difference between Frame Relay and T1

"rockchalk" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> I'm trying to find information about how a 512K Frame Relay circuit is
> different with regard to performance, reliability, etc. compared to a
> T1.  This connection would be from our location to the internet (not a
> point-to-point to another of our locations).  Specifically I am hoping
> to find ways to prove that a T1 internet connection is better for our
> school district than the 512K Frame Relay that we presently have.  In
> the future, we will be looking into things such as VPNs, video
> conferencing, distance learning, etc. if that information is helpful.
> This is definitely not my area of expertise so I appreciate the help.

T1 speed is always 1.536 (or 1.544 Mbps), fixed at that speed forever.
Perhaps think of T1 as the Layer 1 (Physical Layer) technology that provides
physical connectivity from you to your ISP.

Your 512 Kbps Frame Relay connection actually utilizes a T1 or fractional T1
for physical connectivity from you to your ISP ... the difference is that
Frame Relay is the Data Link Layer functionality riding on top of (or, more
precisely, using the services offered by) the Physical Layer of T1.  (And in
case you don't understand Fractional T1, carriers offer 64 Kbps "chunks": of
T1's 1.536 Mbps, with several chunks working together to provide 256 Kbps,
384 Kbps, 512 Kbps and so on ... up to the full speed of the T1 line.)

512 Kbps is the speed of your Frame Relay PVC (permanent virtual circuit).
But you aren't necessarily limited to 512 Kbps .... there are two other
limiting factors:

1.  The speed of the T1 or fractional T1 line.  You'll never be able to
exceed that speed.

2. But there's another detail that you need to understand -- the Frame Relay
port speed.  This speed is contracted between you and the carrier, and
ultimately limits how fast all Frame Relay PVCs may simultaneously
transmit.(still, not exceeding the physical speed of the line, as above in
item 1).

You probably have a port speed of 768 Kbps, and you may have a Fractional
T1, also provisioned to run at 768 Kbps.  If this assumption is correction,
then your FR will allow you to burst up to 768 Kbps for short periods, even
though your PVC's rated speed is only 512 Kbps.

If you want to go faster, then you'll need both a faster FR port speed, and
a faster fractional T1 (or a full T1).

If the only two points on the Frame Relay network are you and the ISP, then
a point-to-point T1 (without Frame Relay) will get you 1.536 Mbps at a price
cheaper than Frame Relay -- at least from the perspective of the carrier.
The ISP may very well charge more for point-to-point T1 than for a FR
connection -- because they can assign one physical telco line (the T1 line)
to handle several customers over the same FR cloud, all sharing the T1
speed.  If they break out your connection to a dedicated physical connection
that only serves you (in order to give you full T1 speed), they might well
charge you substantially more.

If I can help with more information, or provide consulting services, please
let me know.  Just reply, removing the crazy parts of my email address
designed to make life more difficult for people sweeping the 'Net for email
addresses.