linux-wireless.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andy Green <andy@warmcat.com>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: Ulrich Kunitz <kune@deine-taler.de>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	Daniel Drake <dsd@gentoo.org>
Subject: Re: mac80211 driver interface semantics
Date: Mon, 06 Aug 2007 09:25:32 +0100	[thread overview]
Message-ID: <46B6DAFC.7020301@warmcat.com> (raw)
In-Reply-To: <1186382658.21957.45.camel@johannes.berg>

Somebody in the thread at some point said:
> On Fri, 2007-08-03 at 11:49 +0100, Andy Green wrote:
> 
>> ''Because if you have both a hard monitor and a regular interface
>> (monitor_during_oper allowed) then we will never check the CRC on frames
>> that enter the networking path and can get corrupted TCP packets in etc.''
>>
>> If the rest of the networking stack didn't trust the packet anyway and
>> confirms the IP-level checksum, then it can make its own opinion about
>> the packet.
> 
> Maybe it helps if I add that the FCS covers more of the packet than the
> IP checksum; hence, if the FCS fails due to a bit in the area the IP
> checksum does not cover we will not ACK the packet and get a
> retransmission, but the IP checksum will check out as good and we'll
> have a duplicate packet.

Fair enough, thanks for the explanation.

-Andy

      reply	other threads:[~2007-08-06  8:25 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-08-03  0:30 mac80211 driver interface semantics Daniel Drake
2007-08-03  5:29 ` Ulrich Kunitz
2007-08-03  7:59   ` Andy Green
2007-08-03  9:54     ` Johannes Berg
2007-08-03 10:20       ` Joerg Mayer
2007-08-03 10:27       ` Andy Green
2007-08-03 10:32         ` Johannes Berg
2007-08-03 10:35           ` Andy Green
2007-08-03 10:41             ` Johannes Berg
2007-08-03 10:49               ` Andy Green
2007-08-06  6:44                 ` Johannes Berg
2007-08-06  8:25                   ` Andy Green [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=46B6DAFC.7020301@warmcat.com \
    --to=andy@warmcat.com \
    --cc=dsd@gentoo.org \
    --cc=johannes@sipsolutions.net \
    --cc=kune@deine-taler.de \
    --cc=linux-wireless@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).