[e2e] is IP address portability next?

[Dave Crocker]

Henning,


>>       particular Internet access port.  The string entered by typical users is
>>       already independent of the network service provider.

HS> Excepting maybe 20 million or so users (in the US) that have @aol.com 
HS> addresses, in addition to the others that have ISP-provided email 
HS> addresses.

Good point.  This suggests that any user/group without their own domain
name experiences the same addressing lock-in as telephone users have.

However...


HS> Given that most ISPs now prevent users from running MTAs and 
HS> that they enforce using a From address reflecting the ISP,

I think this is not correct, as universally as you suggest.  An issue,
yes, but not a universal.

Port 25 is sometimes blocked, but that's not universal.  The claim that
it is effective for blocking spam is mostly discounted among the
technical and operations community, but the practise does persist.

However, alternate ports, such as for Submit, are typically not blocked.
And of course, neither is port 80, which is used for web-based mail
service access.

In any event, most ISPs do support private domain names.  They'll
typically charge extra, of course, but they do support it.  And, of
course, it takes too much technical savvy to use one.

d/
--
 Dave Crocker <dcrocker-at-brandenburg-dot-com>
 Brandenburg InternetWorking <www.brandenburg.com>
 Sunnyvale, CA  USA <tel:+1.408.246.8253>