[olug] bad practices at home

[Brian Roberson]

aux:~ # traceroute home.bstc.net
traceroute to gomer.bstc.net (24.3.252.27), 30 hops max, 40 byte packets
 1  (REMOVED)
 2  (REMOVED)
 3  500.Serial1-3.GW4.MSP1.ALTER.NET (157.130.100.89)  15 ms  15 ms  15
ms
 4  0.so4-3-0.XR2.CHI2.ALTER.NET (152.63.67.238)  15 ms  15 ms  15 ms
 5  POS7-0.BR2.CHI2.ALTER.NET (152.63.67.245)  15 ms  15 ms  15 ms
 6  137.39.52.106 (137.39.52.106)  16 ms  16 ms  16 ms
 7  c2-pos10-0.chcgil1.home.net (24.7.77.170)  18 ms  19 ms  18 ms
 8  c1-pos2-0.desmia1.home.net (24.7.64.165)  24 ms  24 ms  24 ms
 9  c1-pos2-0.omahne1.home.net (24.7.64.137)  30 ms  29 ms  29 ms
 10  bb1-pos1-1.rdc1.ne.home.net (24.7.75.250)  30 ms  30 ms  30 ms
 11  10.88.40.70 (10.88.40.70)  31 ms  31 ms  31 ms
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is a Bad idea, not matter what way you want to look at it. 
( yes, I removed my packet filters on my core routers to allow 10.x.x.x
through, just for this display )
There are internal and external repercussions that are so great, that I
personally cannot think of any good reason to resort to this type of ip
engineering.

This is not a flame at you adam, just IMHO :-)


-----Original Message-----
From: Adam Korab [mailto:adam at ledhazard.net] 
Sent: Monday, May 21, 2001 12:37 AM
To: olug at bstc.net
Subject: Re: [olug] bad practices at home


On Mon, May 21, 2001 at 12:21:35AM -0500, Brian Roberson wrote:
> I would have to side with Vincent on this. It is bad mojo when you 
> cant pull out a ip subnet calculator and do proper sub/supernetting. 
> Being as wide spread as @home, and owning an entire class A subnet, 
> what are they thinking? However, it is not in any RFC that you must 
> use public ip space from edge-to-edge. I think the reason they are 
> doing this is that

Right, but there is an RFC1918 that says that the 10/8 subnet is
reserved for internal use.  A while back on another list I read there
was a lengthy thread about wheter having RFC1918 addresses on router
interfaces could break MTU path discovery.  The general upshot is that
the RFC specifically says that no packets with a reserved address in the
header (source or destination) should 
leave the network in question.  Also, the RFC says it is not at all 
unreasonable (but not required) for a network to filter packets with 
RFC1918 addresses in the source.  (To prevent attacks and things like
that.)

Comments/flames/discussion welcome.

--Adam
-- 
"A workstation without a network is like a geek in a field all by
himself. It looks intriguing, unusual and different but no one will come
within 20 feet of it." -- Sun help document

---------------------------------------------------------------------
To unsubscribe, e-mail: olug-unsubscribe at bstc.net
For additional commands, e-mail: olug-help at bstc.net



---------------------------------------------------------------------
To unsubscribe, e-mail: olug-unsubscribe at bstc.net
For additional commands, e-mail: olug-help at bstc.net