Re: [ppsp] FW: New Version Notification for draft-huang-ppsp-extended-tracker-protocol-03.txt

[Arno Bakker <[e-mail]>]

Hi Rachel and all

please see inline.

On 30/07/2013 12:43, Huangyihong (Rachel) wrote:
>
> "1. The peer list of a specific swarm obtained by a peer may be out
> of date":
>
> I always assumed that when the initial peer list received via the
> base protocol is outdated, a peer would send a new CONNECT message
> with a PeerNum attribute to get a new list. So why is extra support
> needed?
>
> [Rachel]: I think the peer should first disconnect from the swarm,
> and then send a new CONNECT message to get a new list. Actually, I
> think this procedure is more complicated than having a new message (
> in this spec, we define a new message FIND) to deal with it.
>

I may have been misreading the base protocol spec for a long time then. 
Table 8 of the base protocol indeed does not list that a "CONNECT 
action=join" while in tracking state is a valid transition. IMHO, I 
think it should for both LEECH and SEED, retrieving a new set of peers 
for the swarm you are in is basic functionality. Or FIND must be moved
into the base protocol spec.


> "2. A peer may have the requirement to inform the tracker its new
> network address when the peer has changed its primary network
> attachment."
>
> a) Isn't this the role of mobile IP? and b) can't the base CONNECT
> handle this?
>
> [Rachel]: I think this case is talking about the peer switches its
> network address during the streaming. For example, a peer is firstly
> using WIFI to connect to the tracker. But during the streaming, the
> WIFI has problem and the peer decides to switch to a wired network
> but it doesn't want to stop the streaming. Actually, I think the base
> CONNECT can't handle it. Because it can't "CONNECT" to the same swarm
> twice, right?
>

There are many IETF drafts to deal with IP-address change, and IMHO 
there is no need to add another one here.

CU,
     Arno