Subject: Re: mboned: AMT SSM addressing

From: Venketesan <[email-masked]>
Date: Thu, 14 Sep 2006 16:40:30 -0700

I am sorry i did not understand completly. 
Your point is if i want to source multicast traffic i shud have AMT 
gateway capability in my host itself?
Now arent the following problems in this:
1. I have to go to IANA to get an anycast prefix for myself i.e each 
host if it has to source SSM traffic?
2. I am already part of a fairly large domain which is multicast 
aware, but the ISP for this domain is not multicast aware. Hence i 
just want to have the AMT at the gateway router so that i have 
efficient multicast paths, that use my existing IP multicast 
infrastructure.
3. About getting native multicast.. my whole problem is to tunnel to 
remote domains and i rely on AMT for this so that i acheive a native 
multicast completly working (at least with MBONE and other AMT capable 
domains).  

>>how do you make the receivers aware of any source/group that is 
mashed up by going through this process?

Follow the SSM ideology which is S,G information is dissipated by out-
of-band means like web page, email or whatever.

thanks,
venkat

----- Original Message -----
From: John Zwiebel <[email-masked]>
Date: Thursday, September 14, 2006 3:55 pm
Subject: Re: mboned: AMT SSM addressing

> 
> On Sep 14, 2006, at 2:50 PM, Venketesan wrote:
> 
> > I had a question about the functioning (fault tolerence) of AMT 
> in a
> > certain situation in SSM described below. If one of the authors or
> > someone could answer it..
> 
> Don't source traffic from an AMT gateway?
> 
> FWIW: how do you make the receivers aware of any source/group that
> is mashed up by going through this process?
> 
> The way I read it, the real source has to be a gateway to make this
> work.  If your source breaks, your gateway breaks at the same time.
> 
> Setting up a router to be an AMT gateway to provide a source
> capability for an entire isolated PIM domain brings up a ton of
> other problems.  IMHO, if you want to source enough traffic that
> you want to have a backup AMT tunnel, you'd be much better off
> getting native multicast.  (Which is the point of AMT -- go native)
> _______________________________________________________________
> user interface: http://darkwing.uoregon.edu/~llynch/mboned.html
> web archive:  http://darkwing.uoregon.edu/~llynch/mboned/
> 
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---

From: John Zwiebel <[email-masked]>
Date: Thu, 14 Sep 2006 17:02:00 -0700

> gateway capability in my host itself?

"should" -- yes

> host if it has to source SSM traffic?

The anycast prefix is for the relay you connect to.

> aware, but the ISP for this domain is not multicast aware.

Don't go any farther.  Change your ISP.
FWIW: setting up AMT to source mpackets remains part of the spec, but
that doesn't mean relays are going to be implemented to support it.

> Hence i

Get a new ISP.

> multicast completly working (at least with MBONE and other AMT capable

The MBONE died years ago.  (Don't hit me shep.)  FWIW, I remember the  
MBONE
fondly as a way to prove that multicast could work over large domains  
(the world)
that was done years ago.  The fact that there are many areas that  
don't support
native multicast and have to be tunneled over, under, around or  
though, doesn't
make the result the "MBONE".  Maybe the Minternet.  :->

Why are your sources inside of a remote domain, isolated from native  
multicast?
Either they aren't important sources or your network design is  
broken.  (IMHO)

AMT implementations -will- support your ability to receive in those  
remote locations.
I look at the requirements for being able to source traffic from an  
AMT gateway
and I cringe.  Its a lot of work for little payback.  If you want to  
do it
though, please don't let my opinion stop you.

Seriously, unless multicast gets deployed natively so that anyone  
anywhere
can send to everyone everywhere, we lose.   Where "lose" is defined  
to mean
we don't accomplish my minimum requirements for success.  (ie, IMHO)
And to make that happen, native is the -only- way to go.

> of-band means like web page, email or whatever.

Then -if- you manage to get a backup gateway, its your responsibility
to redistribute the backup information and your responsibility to  
provide
the protocol to make it 'efficient'.  Sorry.
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