[lkml]   [2000]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: all zeroes/all ones used in host IP's...
Magnus Danielson wrote:
> From: (H. Peter Anvin)
> Subject: Re: all zeroes/all ones used in host IP's...
> Date: 28 Jan 2000 11:55:20 -0800
> > You are, indeed, completely wrong. There rules are that neither the
> > *entire* network portion or the *entire* host portion of the address
> > can be all 0 or all 1.
> No, he is correct if you go by RFC 1122. However, if you are running CIDR you
> are right. It seems most posts on this topic actually misses the pre/post CIDR
> conditions and you really have to read the full section of RFC 1122 and think
> of what class the address at hand has in order to fully interprent the
> paragraph that he quoted correctly.

No, he's not; he claimed there was something magic about each *octet*.
That has never been true, although people have, in the past, been keen
on putting the barriers at octet boundaries.

However, RFC 1122 is obsolete. Everyone uses CIDR these days, and once
you have that, you have the rules I gave. CIDR is Best Current Practice
per RFC 2050.


<> at work, <> in private!
"Unix gives you enough rope to shoot yourself in the foot."

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:56    [W:0.060 / U:1.024 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site