RE: delayed multihoming/mobility set-up

["marcelo bagnulo" <mbagnulo@ing.uc3m.es>]

Hi Christian,

> My preferred time-line would be:

I agree with most of this outline, just a question...

>
> 1) Start a communication using one of the available pairs of src/dest
> addresses.
> 2) If the communication is determined to be worth it (i.e. last long
> enough), engage in "multi-homing signaling" to obtain a "set of
> equivalent addresses"

Wouldn't be possible to exchange additional information once that the outage
has been detected?
This sound a bit strange, i know...
But suppose we are using something like SIM
We start the communication using the AID a one locator without any kind of
validation of the AID
If no outage occurs, the communication continues and no extra overhead is
introduced.
If an outage occurs, the endpoints detect it (for instance helped by the
transport or application layer)
At that time, they start using different source addresses and see if they
reach the other end (this packet has to contain also some validation
information, linking the initial AID with the new source locator)
Now, when the other end receives a packet with a different source address
(and validation information), it starts sending to this new address.

This approach allows to avoid any additional packet exchange until an outage
occurs (when it is needed)

Do you think this may work?

regards, marcelo


> 3) On a transport event such as retransmission time-out, probe alternate
> pairs of src/dest addresses, and pick a "better one" if available.
>
> I would note that a lot of the communication we have today do not meet
> the "worth it" requirement. The top applications in the Internet today
> are web pages, which mostly consist of a large number of very short
> exchanges, and p2p file sharing, which includes its own application
> level tools to deal with multi-homing.
>
> -- Christian Huitema
>