[comp.protocols.tcp-ip] RE A routing mystery -- some small input

enger%gburg.DECnet@BLUTO.SCC.COM ("GBURG::ENGER") (09/03/87)

Being curious, I did some pinging from my direct net-10 host, SCCGATE.SCC.COM
(10.11.0.20).  It has its DEFAULT route set to PURDUE-CS-GW.ARPA.

I ping successfully off of FUZZ.CSC.ORG (128.121.50.20)
JVAX.CCIT.ARIZONA.EDU (128.121.50.100)
JVAX.CCIT.ARIZONA.EDU (128.196.1.1)
NOAO.ARIZONA.EDU (128.196.4.1)

I could not raise a response from NOAO.ARIZONA.EDU (192.31.165.2) for quite
some time.  I made a number of attempts over a 10-15 minute period.
I found this curious, as this is simply the address on the 192.31.165 network
for the machine I had just heard from using the 128.196 network.
Further, I had initially been unable to raise any hosts on 192.31.165, and
after I started to hear from the 192.31.165 side of NOAO.ARIZONA.EDU, I 
also found that I could reach those back hosts, but the ping echo times
were much longer than those obtained from the 128 addressed gateways/hosts.

I checked my routing table.  Here is what I found.

destination net  	gateway

128.121.0		psc.psc.edu

128.196.0		psc.psc.edu

192.31.165		DCEC-MILNET-GW.ARPA

It appears that I'm routing through a MILNET gateway to reach
net 192.31.165.

Hope this info can be of some help to you,
Bob
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