Re: [ftpext] draft-ietf-ftpext2-hash command name and default algorithm

Robert Oslin <> Tue, 18 January 2011 14:37 UTC

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From: Robert Oslin <>
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Date: Tue, 18 Jan 2011 08:40:05 -0600
Thread-Topic: [ftpext] draft-ietf-ftpext2-hash command name and default algorithm
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Subject: Re: [ftpext] draft-ietf-ftpext2-hash command name and default algorithm
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I don't see why we need a reply that includes information the client already knows (hash used, filename, etc.). Only the hash is needed, hence option (a) below. 

Again, I'm not insisting on XCRC over HASH and CRC32 over SHA-1 as the default algorithm; I'm simply make the case that doing so will ease the path for adopting the new standard for most FTP server client/server vendors.

Robert Oslin

-----Original Message-----
From: Sob [] 
Sent: Monday, January 17, 2011 11:58 AM
Subject: Re: [ftpext] draft-ietf-ftpext2-hash command name and default algorithm

At 17:04 17.1.2011, Robert Oslin wrote:
>I believe it would make life easier on developers and speed the 
>adoption of your RFC if you considered changing the following:
>1. Keep the command XCRC ...
>2. Keep the default hash CRC32 ...

You would have to keep one more thing, "250 <crc>" as default (or 
only) reply format, otherwise old clients with knowledge of only the 
old XCRC wouldn't know what to do with it.

So you can either:

a) scratch all new reply format ideas and stick with the old one; 
after all, it shouldn't be that hard for client to remember what it 
asked for (filename, range, hash type)

b) force new clients to support two completely different reply 
formats, otherwise they wouldn't understand old servers and the 
"instant success" would not happen; again, it's probably doable, 
developers are clever people and the two formats should be different 
enough to get properly recognized

But essentially it would still be two different commands, only with 
the same name, no real advantage. Old client wouldn't benefit from 
new server and the other way around.