ietf-smtp
[Top] [All Lists]

Re: Existing email address meta-syntax standards, especially GSTN

2008-05-22 10:29:23


On May 21, 2008, at 6:46 PM, Douglas Otis wrote:
RFC 3340,1,3 apex=

RFC 3191 [/] SMS= (example)
RFC 3192 FAX=
RFC 3804 VPIM=, VOICE=, AMIS=

http://www.openspf.org/SRS

(original paper used "#" instead of "=" and example uses "+")

http://www.libsrs2.org/srs/srs.pdf
SRS0=
SRS1=

http://cr.yp.to/proto/verp.txt

Where "=" replaces "@" for local-part cascaded addresses.

list-lp"-"subscrib-lp"="subscrib-dom(_at_)list-dom

This means verp overlaps with "tag=" convention.


By changing the BATV tag ABNF from:

tag-type         = 1*( DIGIT / ALPHA / "-" )

to:

tag-type         = ALPHA *( ALPHA / DIGIT )

BATV could then rely upon the use of the "-" in Verp to ensure differentiation.



By omitting the timer, a need to standardize algorithms is driven solely by the need to ensure compatible tag generation. When only a secret change permits the generation of tags, some of the timer digits should be allocated as selectors.

One implementation might be:

"pih="[pass-phrase:1][index:3][hash:4]"="

Where index is incremented when abuse is detected.


Another might be:

"pwh="[pass-phrase:1][week:2][hash:4]"=".

week = (((epoch-sec + hash(pass-phrase) % 604800) % 31449600) / 604800;

hash = hash(pass-phrase + email-address + week + tag) % 65535;

The week interval would include an induced error to distribute the impact the change may make.

This would tend to automate dealing with abuse, rather than requiring a response.

-Doug