Hi Tore, thanks, that's an interesting idea, we'll look into it and investigate how best to set up an experiment. Regards, Vesna On 10/23/12 10:02 PM, Tore Anderson wrote:

Here's a suggestion for an Atlas experiment and subsequent RIPE Labs article. Do a ping measurement from all the probes to the .0 and .255 address of the same /24, plus to another control address in the same /24, and compare success rates.

It's particularly interesting for me as my own personal home page is accessible at 87.238.60.0 at the moment..,

Might also be worth checking it out for IPv6 at the same time (at least the case where the last 64 bits are all zeroes).

Tore

-------- Opprinnelig melding -------- Emne: Issues encountered with assigning .0 and .255 as usable addresses? Dato: Mon, 22 Oct 2012 22:07:50 +0000 Fra: Paul Zugnoni <paul.zugnoni@jivesoftware.com> Til: nanog@nanog.org <nanog@nanog.org>

Curious whether it's commonplace to find systems that automatically regard .0 and .255 IP addresses (ipv4) as src/dst in packets as traffic that should be considered invalid. When you have a pool of assignable addresses, you should expect to see x.x.x.0 and x.x.x.255 in passing traffic (ie. VIP or NAT pool, or subnets larger than /24). Yet I've run into a commercial IP mgmt product and getting reports of M$ ISA proxy that is specifically blocking traffic for an IP ending in .0 or .255.

Any experience or recommendations? Besides replace the ISA proxy…. Since it's not mine to replace. Also curious whether there's an RFC recommending against the use of .0 or .255 addresses for this reason.