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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Cisco Flash help needed
>I've come across 2 CRCs so far - a 32 bit one used on the Class A cards, >and a 16 bit one used on the Class B cards. I've tried a standard crc32 >routine (stolen from ssh), but it doesn't match the CRC reported by the >router. Is there anyone good at understanding CRC routines who can help me >reverse-engineer the cisco CRC, or perhaps does someone have some inside >information they would like to share? After some suggestions from various people, I tried uploading a few test files onto a Cisco and seeing how the CRCs worked out. It turns out it's not a true CRC at all, but rather a variation on the TCP checksum algorithm. >Please don't ask me for the code yet! I'll let the list know when it's >available... v0.1 of the code is now available (read only at the moment): ftp://ftp.bbc.co.uk/pub/ciscoflash/ Enjoy, Simon -- Simon Lockhart | Tel: +44 (0)1737 839676 Internet Engineering Manager | Fax: +44 (0)1737 839516 BBC Internet Services | Email: [email protected] Kingswood Warren,Tadworth,Surrey,UK | URL: http://support.bbc.co.uk/
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