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RE: Reqt. 3.1.1 [was Re: (multi6) requirements draft comments]



Brian,

>> Brian Carpenter wrote:
>> The reason I've railed against Tony's PI proposal is because I
>> have serious doubts whether market forces will lead to the
>> adoption of metro (or metro-like) addressing and the consequent
>> creation of ISP-neutral metro exchanges.

I don't see why ISP-neutral metro exchanges would be needed. What
I find in Tony's draft is an adressing scheme. What you wrote above
leads me to think that you envision this geo addressing as being the
only address being used. It does not need to. If sites use their PA
address in combination with Tony's PI address, there is no need for
local exchanges.

>> However, returning to our topic, that would make the metro
>> exchanges key failure points in the multihoming system.
>> That breaks requirement 3.1.1 in the draft. Do we want to
>> insist that the solution MUST accommodate failure of metro
>> exchanges?

Again, metro exchanges are not necessarily needed. Going back to the
problem at hand, what we are bumping into is route aggregation.
Let's take the following example:

- A site is connected trough multiple transit providers. That site
advertises its PI prefix to all its transit providers and each PA
prefix only to the provider it belongs to.
- The transport of the actual traffic will use MHTP as described in
http://search.ietf.org/internet-drafts/draft-py-multi6-mhtp-01.txt
(Although the draft describes centrally allocated PI addresses, it
could easily use Tony's PI address scheme as well).
- Data is actually transported over PA addresses.
- The providers do not need to be connected together to a regional
exchange. All they need to do is to aggregate the regional routes
in order to keep the routing table small.

In other words: there is no need for a PI geographical infrastructure.
All is needed is PI geographical route aggregation, which is a lot
less work for the transit providers.

I would support working on Tony's draft when we actually can make
proposals working group documents. I agree that the creation of
ISP-neutral metro exchanges would probably not happen, but since
they are not needed I do see a lot of value in geo addressing.

Michel.