Date: Wed, 25 Mar 1998 13:33:42 -0500 (EST) From: "Ron G. Minnich" <rminnich@Sarnoff.COM> To: freebsd-hackers@FreeBSD.ORG Subject: Re: ARP REQUEST question Message-ID: <Pine.SUN.3.91.980325133056.9569D-100000@terra> In-Reply-To: <Pine.BSF.3.96.980325130952.17889B-100000@phoenix.its.rpi.edu>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, 25 Mar 1998, David E. Cross wrote: > I see what you are saying with corrupted packets being introduced by a > flaky ethernet card, but keep in mind that true 'end to end' detection and > reliability is not possible, if you have a bad memory circut, in the place > wher you are building the packet in the kernel, you are going to get a Don't forget, it's not just on your machine. It's on any device (router or switch) between your memory and the destination computer's memory. That covers a lot of ground. > It is also of note how laughable the Internet checksums are, they are 16 > bit modulo 2^16 checksums, they are NOT CRCs... a simple byte swap can yes, in fact you have just brought to mind one of the very few advantages that ATM has over both Ethernet and IP checksums: ATM AAL5 has a CRC-32 (as good as ethernet, much better than IP) that is end-to-end (as good as IP, much better than Ethernet). There's only a few places where ATM is a winner, and this is one of them. ron To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.SUN.3.91.980325133056.9569D-100000>