From: "Milan P. Stanic" <mps@arvanta.net>
To: linux-ppp@vger.kernel.org
Subject: Re: CRC-16 or CRC-32
Date: Tue, 20 Apr 2010 15:10:09 +0000 [thread overview]
Message-ID: <20100420151008.GB16143@arvanta.net> (raw)
In-Reply-To: <291B2C7721AC7B49AD11449A2883992E2C4A9BDC3C@SINTEFEXMBX01.sintef.no>
On Tue, 2010-04-20 at 16:49, Jan Just Keijser wrote:
> Arne Lie wrote:
> >Hm, my observations are that if there are bit errors introduced in the PPP frame, the "ifconfig ppp0" will count such packets in the "error" tab. From this I anticipated that the PPP stack included CRC checking of its payload. By CRC-16 I mean 2 byte CRC, CRC-32 4 byte. Our customer wants 4 byte CRC. From RFC2823 I see both are mentioned. The question is, how does one select either? Perhaps it is not configurable via pppd?
> >
> RFC2823 is about PPP SDL on SONET/SDH ; AFAIK the pppd code does not
> support this *at all* so I am not surprised that I did not find any
> references to CRCs in the headers...
>
> So the short answer to your question would be: no, PPP v2.4.5 does
> not support CRC-16 or CRC-32.
In Linu CRC is done in kernel ppp driver not the ppp daemon.
ZLIB compression uses crc-32, AFAIR.
--
Kind regards, Milan
--------------------------------------------------
Arvanta, IT Security http://www.arvanta.net
Please do not send me e-mail containing HTML code.
next prev parent reply other threads:[~2010-04-20 15:10 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-20 9:42 CRC-16 or CRC-32 Arne Lie
2010-04-20 14:16 ` Jan Just Keijser
2010-04-20 14:38 ` Arne Lie
2010-04-20 14:49 ` Jan Just Keijser
2010-04-20 15:10 ` Milan P. Stanic [this message]
2010-04-21 6:56 ` Arne Lie
2010-04-21 8:10 ` Jan Just Keijser
2010-04-21 9:08 ` Milan P. Stanic
2010-04-21 9:17 ` Milan P. Stanic
2010-04-23 3:46 ` James Carlson
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