[Nsi-wg] STPs in NSI v2.0

[Henrik Thostrup Jensen]

On Wed, 11 Jul 2012, Freek Dijkstra wrote:

> On 11-07-2012 11:09, Henrik Thostrup Jensen wrote:
>
>> In some aspect VLAN is part of the data we
>> move around so it shouldn't really be touched, however they are so used
>> that it is something we have to support with the quirks that come with it.
>
> I disagree, to me the VLAN is part of the header, not of the data
> stream. I presume that the actual end-user submits his/hers data to the
> network without VLAN, even though by the time it reaches the first STP
> the network provider will likely added a VLAN to the data.

This is all a matter of perspective, and what the user wants. I don't see 
there being any right or wrong. Jerry have though a lot about what to do 
with framing and so, so I'll let him fill out the details here :-).

> Would it be useful to distinguish between a C-VLAN (which I consider
> part of the data stream) and the S-VLAN and/or I-SID (which I consider
> part of the ISP headers)?  (and you may now point me at the fact that I
> mixed C-VLAN and S-VLAN in my previous message, oops.)

I don't know. But we need to have some semantics about framing and what 
will happen with it.

> Perhaps more important: I presume most STP will be a 802.1Q Ethernet
> interface, thus with VLAN tags.

It is likely. I don't know. I'd suppose regular untagged ethernet and IP 
being rather common as well.

I still think the whole ethernet/VLAN interface is silly. The first thing 
users (and ourselves) do is to put IP on top of it. A "good" user 
interface towards NSI will ask for the IPs you'll want the bandwidth 
between and bandwidth in each direction, and then figure out the rest. Of 
course this should not be the base abstraction in NSI, but something that 
can be built on top of what we have.

> Would NSI also support a STP without VLAN tags?

Most definitely yes (IMHO).


     Best regards, Henrik

  Henrik Thostrup Jensen <htj at nordu.net>
  Software Developer, NORDUnet