On 2004-06-01T05:28:37-0400, Adam Back wrote: > > Putting extra stuff into the header makes line-length an issue, > > I think we are already close to having a line-length issue, especially > if we include sub-puzzles. Practically you want sub-80-chars. Isn't an 80 character limit unnecessary? I looked through my mailbox, and Exchange has a 40-byte hex field at the beginning of its message-id, which tends to make its message ids extremely long (given the penchant of Windows admins to name machines exchange-01-sjc.foo.bar.baz.subdivision.company.com). I have a handful of messages with 90+ character Exchange-generated MID headers that aren't line-wrapped. > > X:0405310625:hashcash@xxxxxxxxxxxxx:25:sender@xxxxxxxxxxxxxx:asdlkfj1325ASDFJ I don't like the idea I suggested of including the sender's address, and you're right, a good base64 random field is just as good as a timestamp. Implementations could even use the 16.4 bits of HHMMSS information and put that in the high 18 bits of the random field, saving 3 bytes of stamp length. Is the length of the random field fixed in v1? In v0 it was fixed at 96 bits, right? > > I understand the rationale behind multiple puzzles, but people sending > > generating stamps should allow that it might take up to an order of > > magnitude longer than normal. If I expect a stamp to take 1 minute, I'm > > not going to get bent out of shape if it takes 5 minutes to deliver. If > > messages are time-critical, make sure the recipient has you whitelisted > > Well if the postage generation is done in the background probably > doesn't matter so much. (Though there is some user expectation > potential problem -- eg dialup, I want to know when its gone so I can > hangup). Well that's a problem, but minting could also take much longer than expected with sub-puzzles. Unless common stamp values are so small they have six-sigma time bounds of 10-20 seconds, I don't think foreground stamp generation would fly. I suspect that's near 20 bits at the moment, for most desktop machines. -- "Not your decision to make." "Yes. But it's the right decision, and I made it for my daughter." - Bill, Beatrix; Kill Bill Vol. 2