Thanks Jeroen. The introduction of the separate layer as a concept is to help formalize the separation of concerns by handling errors at the MTL layer. If you look at NSI v1, the state machine was integrated and would mean that the state machine would change if you changed the requirements for the MTL layer. This is not the case with NSI v2.0. When people are talking about different MTL's, then we need to make sure that a change in MTL will not change the NSI state machine. The MDL makes that possible.

From your messages, I believe you agree this functionality is needed in NSA. What you are disagreeing is the formalization of that functionality into a layer. Maybe the NSI group can comment on that as well or you can make a formal proposal to the group to change it?

Inder



On Wed, Dec 12, 2012 at 2:55 AM, Jeroen van der Ham <vdham@uva.nl> wrote:
Hi,

On 12 Dec 2012, at 11:34, Inder Monga <imonga@es.net> wrote:

> Jeroen,
>
> What solution are you proposing - it is not clear?

I'm proposing to simplify things, to not introduce another layer, and simply describe that the NSI expects the NSA to make an effort in delivering a message. It should use the reliable MTL (which we've defined to be SOAP). If that fails, then it is up to the NSAs discretion to fail directly, or to make an extra effort and try again. Ultimately, it will either fail or it will succeed.

To me, it seems like a simple statement that can be added to the document. For example where you describe when you go from a state to the failed state.

Jeroen.