I believe that Melinda discusses a method for transmitting data thru hostile gateways in her paper on Rita.
-----Original Message----- From: CMSTSO Pipelines Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Paul Gilmartin Sent: Tuesday, July 31, 2007 11:20 AM To: [email protected] Subject: [CMS-PIPELINES] Checksums? CRC? (and hex display?) Looking for data validation, I find the CRC stage. But 16-bit checksums are much in disrepute -- probably good enough for detecting noise, but not sound cryptographically. (Heck, even the 128-bit MD5 is now suspect.) Is better available somewhere? SHA-1? Or even the lowly MD5? Weakness notwithstanding, MD5 has the advantage of being readily available on other platforms. And I readily suspected and proved a weakness in PIPE CRC: files with content: a bc and: ab c show identical CRC checksums -- apparently the algorithm ignores record boundaries. This is unfortunate because such framing errors are readily introduced by transfer to a stream-oriented workstation and back. And consider Melinda's(?) assertion that CMS Pipelines is superior to other pipe utilities because not all data should be treated as streams. I suppose PIPE PACK | CRC can be used to overcome the record boundary deficiency. For my testing, I would have liked a stage comparable to the Rexx C2X function. Of course, it's easy to write, but has someone else already invented that wheel? Thanks, gil -- StorageTek INFORMATION made POWERFUL
