NetNews Usenet Archive 1993 #3/NN_1993_3.iso/spool/comp/protocol/nfs/3188

Internet Message Format | 1993-01-21 | 4.8 KB

Xref: sparky comp.protocols.nfs:3188 comp.dcom.isdn:1199
Newsgroups: comp.protocols.nfs,comp.dcom.isdn
Path: sparky!uunet!cs.utexas.edu!torn!nott!hobbit.gandalf.ca!dcarr
From: [e-mail] (Dave Carr)
Subject: Re: Low cost ether/isdn brouters (was PC-NFS PPP Serial/ISDN driver wanted)
Message-ID: <[e-mail]>
Organization: Gandalf Data Ltd.
References: <[e-mail]> <[e-mail]> <[e-mail]>
Distribution: na
Date: Thu, 21 Jan 1993 22:47:40 GMT
Lines: 89

In <[e-mail]> [e-mail] (Vernon Schryver) writes:

>In article <[e-mail]>, [e-mail] (Dave Carr) writes:
>> ...
>> >Just 2x64k (uncompressed would be ok), with real router sw (SNMP, RIP, ARP,
>> >OSI?) rather than a filtering bridge is what I want. However it can be

>I've argued vigorously with Gandalf representatives about their
>"brouter."  (Which word I hope they have removed from the brochure
>describing their half-bridge!)  Their position was "<big company> told

Point noted.  Marketting has been told.  But please, the 5510 is not
my favourite product either.  The 5510 isn't even a half-bridge.

Try a 5220.  And if you want a router with the same feature (data
compression, SNMP,...) for under $3000, wait a couple of months.

>Many who want to run network stuff over ISDN have real networks on both
>sides of the point-to-point link.  This applies just as much to
>companies who might replace leased lines in large "WAN's" with ISDN
>links as it does to individuals.  Individuals may often have only 1 or
>2 computers and a printer, but the reasons they have for treating their
>local network as something other than a bridged extension of the
>other network are similar.

Try the 5220i.  Not a misprint.  The 5200i can dial on demand, and only
brings the link up when needed.  Shoot, it even looks at ARPs and IP
addresses.  So tell me, is a router or a bridge.

>If bridging were always the right answer for corporate WAN's, then none
>of those point-to-point links would not be using routers.

Of course I'm right, and CISCO is wrong :-) Get real.

>If your argument were valid, "just fix the MAC group address bit
>problems and then bridges are enough", then there would be no market
>for routers.  If your argument were valid, then Cicso would not be in
>business, and neither would Wellfleet.   Instead, there would only be
>companies making clones of DEC bridges.

I made no such claim.  A bridge cannot replace a router.  But a router
IS overkill for many applications.  Especially for replacing V.32 modems
in a dialup application.  What do you want, a CISCO at home.  You must
have a big net at home if you need BGP.  And I thought all you needed was
OSPF at home.

I'm not trying to say that bridges are better.  Both have their places.

>IP routing does not require "100's of KBbytes of code".  Just how big
>is ka9q?

Is that all you want.  Buy the 5220i.  Now if you want an IP/DECNET/
APPLETALK/... router, plus OSPF/BGP/RIP/... then you are talking 800K.
The stacks take memory.

>Consider one example.  Assume you are employeed by <big company> and
>want to run ISDN to the corporate network to work at night.  Assume you
>have only 1 PC running 386BSD on your ethernet.  What if you also want
>to connect your machine a low cost Internet provider ($1/hour PPP or
>SLIP) to participate in mailing lists or to get source that <big
>company> might not appreciate?  Or maybe the firewall between the
>corporate network at <big company> and the Internet is inconvenient or
>too high for you.  If you have a real network and a real ISDN router,
>you can route directly to the corporate network or to CERFNET or CSN at
>will.  In this example if you have only a bridge, you have either a
>white elephant or a set of shackles locking you to the company network.

The 5220i can dial different ISDN numbers to get to different IP
addresses.  Okay, it's a static router.  Some limitations apply.
What's the equivalent CISCO box sell for?  What's that, you want
compression.  Sorry.  We're Cisco, you don't need compression.
And yes, I would have to go througH a router eventually to get to the
internet, but so would your router from home.

>Finally, I notice that you posted this to comp.protocols.nfs.  That
>suggests you are thinking about running NFS over your ISDN boxes.  NFS
>usually implies NIS.  NIS almost always involves broadcast packets.
>How are you going to "eliminate these [broadcast] packets"?

Sure, why not.  After all, a bridge doesn't discriminate on the basis
of protocol :-)

From what angle?  If bandwidth on the link is the problem, then I'll
ask "How much information content is in a broadcast? In the second?"
Know what compression does to these packets?

If your assuming that I am going to filter all broadcast and therefore
NIS packets won't get through, that's a wrong assumption.