Re: [MBONED] draft-zhou-mboned-multrans-path-optimization

["Lee, Yiu" <[e-mail]>]

Hi Stig,

On 3/23/12 2:43 PM, "Stig Venaas" <[e-mail]> wrote:

>Please don't get me wrong. I want to avoid translation as much as
>possible. Hence I also want to avoid double translation, although it
>might in some cases be better than tunneling.
>
>Some general things to consider are IMO
>
>1. Is it bad if multiple independent devices are performing the same
>    translation of the same data?
>
>    Translation at the source may guarantee it happens at most once.
>    Translation further down the tree may result in multiple devices
>    doing the same translation. Bandwidth is the main reason not to do
>    it at the source in a dual-stack network.
>
>2. With multiple translators, can we ensure that packets don't get
>    double translated unnecessary?
>
>    Basically if the network is dual-stack, can one make sure that
>    there never will be more than one translator on the path between
>    any source-receiver pair?

These are interesting questions. IMHO, if we can deploy the translator
closer to the access network and connect the source directly to the
translator, this could be the most trivial setup. If the sources are
placed high-up in the network and multiple translators are involved, that
may require some intelligence in the translator. I agree what you said, we
may need more than simple matrix to design what situation the translate
should translate the stream. It is also not simple to decide a v6 stream
using native v6 address is equal to a v4 stream using v4-embedded v6
address in term on content. When we have a mixed environment, we need to
know what deployment problem we are trying to solve.

B.R.,
Yiu