Subject: RE: Updating of mSLP draft-08

From: Mikael Pahmp <[email-masked]>
Date: Mon, 25 Sep 2000 11:09:34 +0200

> -----Original Message-----
> From: Weibin Zhao [mailto:[email-masked]]
> 
> 
> 
> (2) Using the "mesh-forwarding" extension in the above data transfer. 
> 
>     During the above data transfer, the requested data are sent as SrvReg
>     messages. All these SrvReg messages SHOULD have the "mesh-forwarding"
>     extension to request the receiving DA forwards the message to all of its
>     existing peers. The reason for this can be illustrated in the following
>     example. Considering that DA1, DA2 and DA3 all serve the same scopes.
>     DA1 and DA2 set up a peer relationship first, DA3 joins them later.
>     When DA3 joins DA1 and DA2, assume that all of them have already had 
>     some data. DA1 and DA2 have got synchronized since they are peer already.
>     Now, say that DA3 discovers DA1 first, DA3 exchanges data with DA1. DA1 
>     forwards the data it received from DA3 to DA2. Later, when DA3 discovers
>     DA2, since both DA3 and DA2 peer with DA1, they do not need to exchange
>     data.

When DA3 and DA1 has exchanged data, they both know that they are in sync and DA3 knows that it is also in sync with DA2 because DA1 forwarded the SrvRegs from DA3. So when DA3 sets up a peer connection with DA2, it will not request data from DA2 but how about DA2? Does he know that he is in sync with DA3 (since DA1 forwarder all SrvRegs) or will he still request data from DA3?

/Mikael

---

From: Weibin Zhao <[email-masked]>
Date: Mon, 25 Sep 2000 10:14:37 -0400 (EDT)

Hi Mikael,

The idea is that when a mesh-enhanced DA handles the peer relationship 
setup procedure with peer DAs, it synchronizes data with one peer
at each time. This can avoid race conditions in data synchronization
among peer DAs.

mSLP uses "Peer_DA_Indication", "Data_Copy_Rqst" and "Data_Send_Done"
MeshCtrl messages for data synchronization.

In the example, DA3 sends a "Peer_DA_Indication" to DA2 *AFTER* it have got
sychronized with DA1 and informs DA2 that it peers with DA1 in this
"Peer_DA_Indication". DA2 also sends a "Peer_DA_Indication" to DA3 in 
which it informs DA3 that it peers with DA1. Since both DA3 and DA2 peer
with DA1, and they know the other party also peers with DA1, they do 
not need to exchange data.

-Weibin

----------------------------------------
On Mon, 25 Sep 2000, Mikael Pahmp wrote:

When DA3 and DA1 has exchanged data, they both know that they are in sync 
and DA3 knows that it is also in sync with DA2 because DA1 forwarded the 
SrvRegs from DA3. So when DA3 sets up a peer connection with DA2, it will 
not request data from DA2 but how about DA2? Does he know that he is in sync
with DA3 (since DA1 forwarder all SrvRegs) or will he still request data 
from DA3?