From: Bakul Shah <bakul@iitbombay.org>
To: Warner Losh <imp@bsdimp.com>
Cc: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] conventions around zero padding in ip4
Date: Sat, 7 May 2022 16:19:53 -0700 [thread overview]
Message-ID: <FA943880-F763-4548-A7AC-0BDB9991E731@iitbombay.org> (raw)
In-Reply-To: <CANCZdfpsFbB7A4+aaiNwc=cCVzu=sLpSx8V7ekka6TGhtYxvLQ@mail.gmail.com>
On May 7, 2022, at 12:14 PM, Warner Losh <imp@bsdimp.com> wrote:
>
> 10.2 is ambiguous. In a network context, it means, typically, 10.2.0.0/16 (though your mileage may vary).
> In a host context, it means 10.0.0.2. It's this confusion that has lead to many efforts
> to outright kill this notation.
On FreeBSD:
ping 10.2 tries to ping 10.0.0.2 and
ping 192.168.300 tries to ping 192.168.1.44 (1*2^8+44 == 300)
ping 10.2.300 tries to ping 10.2.1.44
ping 192.1000000 tries to ping 192.15.66.64 (15*2^15+66*2^8+64 == 1000000)
ping 1000000001 tries to ping 59.154.202.1 (59*2^24+154*2^16+202*2^8+1)
ping 300.300 tries to ping 23.217.138.110 (I haven't worked this out! Prob. a bug)
So the last number is treated as the host number on a given net.
This may have some sense in the classful network world but is
very confusing in the CIDR world.
next prev parent reply other threads:[~2022-05-07 23:22 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-07 16:14 ron minnich
2022-05-07 16:38 ` Bakul Shah
2022-05-07 16:48 ` Erik E. Fair
2022-05-07 18:49 ` Steffen Nurpmeso
2022-05-07 19:14 ` Warner Losh
2022-05-07 19:50 ` ron minnich
2022-05-07 19:57 ` ron minnich
2022-05-07 23:19 ` Bakul Shah [this message]
2022-05-07 23:49 ` Warner Losh
2022-05-08 10:28 ` Ralph Corderoy
2022-05-08 5:21 ` jason-tuhs
2022-05-08 10:22 ` Ralph Corderoy
2022-05-09 14:08 ` Steffen Nurpmeso
2022-05-10 10:49 ` Ralph Corderoy
2022-05-07 19:43 Noel Chiappa
2022-05-08 14:54 ` Michael Kjörling
2022-05-09 16:14 Noel Chiappa
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