The End-To-End Internet (was Re: Blocking MX query)

Masataka Ohta mohta at
Thu Sep 6 04:41:26 UTC 2012

(2012/09/06 13:15), valdis.kletnieks at wrote:
> On Thu, 06 Sep 2012 13:08:29 +0900, Masataka Ohta said:
>> The end to end transparency can be restored easily, if an
>> administrator wishes so, with UPnP capable NAT and modified
>> host transport layer.
> How does the *second* host behind the NAT that wants to use
> global port 7719 do it?

In the previous mails, I wrote:

> The remaining restrictions are that ...
> and that a set of port
> numbers available to the application layer is limited (you may
> not be able to run a SMTP server at port 25).

and Jimmy wrote:

> At the transport layer, end-to-end means you can establish connections
> on various ports to any peer on the internet, and any peer can connect
> to all ports on which you allow.   It doesn't necessarily mean that
> all ports are allowed;  a remote host, or a firewall under their
> control, deciding to block your connection is not a violation of
> end-to-end.

						Masataka Ohta

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