Subject: Re: RFC-1122
To: Guenther Grau <Guenther.Grau@bk.bosch.de>
From: Matthew Smithshaw <M@ML-Associates.co.uk>
List: tech-net
Date: 08/15/1997 20:30:30
Looks like HP have done a backward step...
If you use Class Addressing, then they are correct, but
the Internet has been using classLESS addressing (CIDR)
now for _quite_ a long time, i.e. you are specifying a /25

I know on cisco routers there is an option for classless
addressing.

Most unix variants never bothered enforcing this (just as
well)

CIDR breaks much class A/B/C based subnet/supernet implementations
Tell HP to read RFC 1520 for some examples.

Check out RFC 1149 - then ask HP if they comply with that.

Remember in todays Internet, we do not think of Class A/B/C,
so a /25 (255.255.255.128) is valid.


Regards


-M
(my 2c worth)

At 11:05 15/08/97 +0200, Guenther Grau wrote:
>Hi,
>
>at work I am "forced" to work with hp-ux ( which is, IMHO, one of the
>worst unix implementations I ever worked with. But I don't want to
>talk about this right now :-). Starting from version 10.x they forbid
>the following netmask: 255.255.255.128 for a class C IP-Address (eg.
>192.13.13.13).
>When I called hp-support they said that this netmask was illegal, citing
>rfc-1122 (well, they also offered me a workaround, because other
>customers had complained about this as well :-). Reading through
>rfc-1122 I found the following passage (page 30):
>
>...
>            IP addresses are not permitted to have the value 0 or -1 for
>            any of the <Host-number>, <Network-number>, or <Subnet-
>            number> fields (except in the special cases listed above).
>            This implies that each of these fields will be at least two
>            bits long.
>
>where -1 means all bits one and the special cases are just broadcast and
>initialisation addresses.
>
>Can anybody explain why this was done?
>
>And my second question: Do we comply to this standard?
>Although I can see no reason for the requirement, we should comply
>and offer a variable which can be set by sysctl to turn this behaviour
>on or off.
>
>  Guenther
>
>
-- 
Matthew Smithshaw                 | ML Associates
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