Barton.Bruce@camb.com (Barton F. Bruce) (04/07/91)
At last! there is now a signigicant and different way to connect ALL
your company's scattered LANs into a big WAN.
Frame relay is here and you can order it. Some thought Sprint would be
first later this year, but WilTel has been beta testing it with some
LARGE customers, and has now announced its general availability.
The actual switches are not yet in all their POPs, but they will bear
the expense of back-hauling your access lines from a switch to the POP
near you.
What is frame relay? Think of a FAST efficient and cheap (and no
packet charges) x.25 network. Your sites will all be part of a CUG
(Closed Users Group) so, though you are on a public net, you traffic
is on your virtual private net.
You need Enet routers that can handle frame relay. Cisco's CAN today.
You need an approved T1 CSU (Datalink's is today). You get to use the
rest of the T1's DS0s for any other leased line type access they can
sell you, since you won't be using all of it for frame relay.
Note well that this is distance insensitive, and look at the pricing!
They are offering two 'port connection' speeds - 256 kbps, and 1024
mbps. These are obviously four and sixteen DS0s out of the T1 access
pipe. The approved CSUs let you gain access to the other DS0s on a
seperate port.
Their service is provided in PVCs (Permanent Virtual Circuits) between
your sites. These PVC have a nominal speed, BUT can support bursts up
to the Port Connection speed. The idea here is that you are paying for
some average amount of transport, but can get peaks that will be
carried. Many companies buy leased lines that vastly exceed their
average load just to cater to the bursty needs of their WAN. This
*may* solve some of these problems at lower cost.
The 'Port Connection' (the ONE physical connection to your cisco box )
supports various lower speed PVCs to many remote sites. Each nominal
PVC speed is also some number of DS0s (64 kb - 1 T1 time slot) of
bandwidth. I am making a N x DS0 column below, because that number
does figure into pricing.
Port Connection PVC speed N x DS0
256 Kbps 56/64 Kbps 1
128 Kbps 2
1.024 Mbps 56/64 Kbps 1
128 Kbps 2
256 4
512 8
This is per site pricing, NO local access lines, etc included. It is
based on the Port Connection speed, and the total of N x DS0s of PVC
bandwidth terminating there. N.B. that you need not subscribe to PVCs
between all possible nodes, and that, depending on traffic, you may
implement anything between a simple star to a full mesh topology. Each
PVC can be whatever speed is needed.
Port Connection Size: 256 K 1.024 Mbps
----- ----------
Total DS0s of PVCs $ $
1 635 1535
2 920 1820
3 1062 2105
4 1176 2390
5 1262 2675
6 1347 2960
7 1404 3245
8 1461 3530
As an example, three nodes A, B, C with A being the central site with
very little traffic between B and C could all use 256 K Ports; A would
use two 64k PVCs ($920), and the two other sites would only have a 64k
PVC to A for $635 each or total for all 3 sites of $2190. If there
needed to be a PVC between B and C, each site would pay $920 for $2760
total.
If your sites are Boston, NYC, and Albany, these prices are terrible
compared to leased 64kb DDS-II lines, but with greater distances, many
more PVCs, and enjoying the benefits of the burst capability, this
sort of offering could look very attractive. Remember also that each
site ONLY needs one high speed serial port into their cisco, not one
for each remote served by a PVC. This is a big savings in cisco
hardware.
This is based on my phone notes after talking to a WilTel sales
critter, and could easily contain many errors, but does give some feel
for the offering. I think this was officially announced last Monday.
Friday I let my Sprint saleswoman go on in detail about how they were
going to be first with frame relay much later this year. I then told
her about WilTel ...
Usual disclaimers: I have NO $ connections to any above companies (not
even as a customer - yet). This is just good stuff we all will need to
know soon.
WilTel is at 1.800.642.2299 - tell them the price is still too high.