▼

Saturday, June 27, 2009

E-mail headers

Aren't computers just complex? Take a simple little thing like e-mail headers, for example. My email app Eudora has settings which hide most of the headers from me, because there are dozens (hundreds?) of them, and I only want date, addresses, subject.

And yet so many odd headers show up. Sometimes I'll get the odd mail where I don't see a single odd, cryptic header, and that's a delight. But sometimes the headers will be like 20 lines, just meaningless code. How come some e-mails need them and some don't?

And look at this one: what in the world, besides military encryption, could need a code for a single header which is this long?? Think: every new character adds like 40 new possibilities.

(Damn, it doesn't wrap in the browser, I'll have to wrap it manually. It was one long line.)
X-YMail-OSG: uj6A4zsVM1kgmxKLDz20vrw8F18K1k0vbUDL
hzb1y7BX36sRZsi7Q2WAtt.DME.YCoIjDKjagTDFAGWJ5.m
CY5i2Rt10pNIsN15_fNdCqGc8Y40klKDYAQaNlL9Yzp9NTcd
3UH1sXpUTxvQ3tZIRPHEtzXkv_sqZ3Kcjdn473YtRfdYATTp
n6481BDFjSk9XXnd.X70Gp1XBro7HE0Xp6bRQ5vZB1Z6tuZ
XVV0kai215k3VapIojTP_cQZ6lYhvd6Tp8ty5zCQ--
at

5 comments:

  1. Chris S.27 Jun 2009, 21:42:00

    Anthing that touches the email on it's way could add headers. For example, spam filters will often add a header or two indicating what status it classes the message with. I've written email client code before and was surprised how simplistic the whole protocol is. Probably one reason it's been so abused over the years.

    ReplyDelete
  2. Eolake Stobblehouse27 Jun 2009, 21:47:00

    Aha. That explains why mails from Amazon has at least three extra headers all of their own.

    ReplyDelete
  3. Dibutil28 Jun 2009, 04:17:00

    This particular header is hashed code which would allow only Yahoo administrators to determine the sender's account @yahoo. This is done for protection of the senders from spam when a Trojan breaks recipient's computer as well as becomes digital proof that this account has sent this e-mail and nobody spoofed it (also helps protect from spam). Big Brother is watching...

    ReplyDelete
  4. Michael Burton28 Jun 2009, 07:02:00

    You can customize which headers are filtered out. Here's how to customize boring headers on a Mac. There's a page at the same site showing you how to customize on a PC.

    I've filtered out any header lines starting with "X-", since those are all extended headers.

    ReplyDelete
  5. Eolake Stobblehouse28 Jun 2009, 10:10:00

    Thanks, DF.

    MB, yes, I've done a lot of that. But new ones keep cropping up. :-)

    ReplyDelete