TELECOM 247

Nigel Kendrick wrote in
message news:43a8829d$0$29560$da0feed9@news.zen.co.uk...

i have done this before with cisco routers.

you can put async modules in the router which make it act like a terminal
server.

the router could drive your existing kilostream link, or an ADSL or other
type of WAN - once you get to 1841 or 2800 routers the WAN interfaces are
modular.

1 thing to remember is that any routed link is not going to be as bandwidth
efficient as the stat mux - all that TCP/IP overhead adds up.

A lot of old kilostream corporate networks have migrated to ADSL. However,
conventional circuits have been getting cheaper for years, so new point to
point links may work out reasonable, even with higher bandwidths.

you can go for a Internet based service (in which case you need encryption
and router security to keep your network walled off from the Internet).
or you could use a private ADSL / IP service (popular with a lot of retail
chains) - most of these seem to be based on an MPLS core. however although
there are a lot of providers, you may find the overhead costs painful with
only 4 sites.

use a modular router and build it the way you need.

i suggest you split this into 2 separate issues
1. what is the end user devices - if they are PCs then you may not need
terminal servers at all
2. what should the transport be (almost certainly IP?) - but then you need
to decide on the underlying WAN.

the other thing is to step back from your current issue and plan what you
want so that it will last for a while, and whether other changes you expect
mean alterations to the WAN in the next few years.

for example, if you still have terminals, there might already be plans to
swap them out for PCs / Citrix terminals. If so your new IP network could
support old kit, new, or both (with enough bandwidth ) depending on the
timescales.
--
Regards

stephen hope@xyzworld.com - replace xyz with ntl