'Today' considers data retention and IMP

[Ian Batten]

>
> (2) I'm not convinced the certificate check IS dealing with a  
> different
>    risk.  The very people most likely to have the ability to passively
>    sniff *backbone* links are probably ISP staff, who could just as  
> easily
>    mount an active attack to defeat opportunistic TLS.  E.g redirect  
> SMTP
>    to a transparent proxy, effectively man-in-the-middle'ing the TLS.

That's a much harder attack to mount, though.  For a two blokes ISP  
it's do-able, but it would require co-ordination across quite a wide  
range of functions with a larger undertaking.  It'd be something an  
ISP undertook, not an ISP employee.

It'd also be fairly easy to spot.  You strew about on other machines  
you control self-signed certificates which you can verify, and use  
those as canaries in the mine.

ian