[c-nsp] ME3600x sub-interfaces

[Pete Lumbis]

I'm sure it had more to do with creating a configuration that follows
MEF standards than anything else, but even if they did shove it all
under a sub-interface you're now talking about completely rewriting
the sub-interface frame handling and data structure components. I
think there'd be more outrage when previously working sub-interfaces
run into bugs after an upgrade than doing all that development on a
new feature.


On Sun, Oct 28, 2012 at 4:43 AM, Saku Ytti <saku at ytti.fi> wrote:
> On (2012-10-27 16:43 -0400), Pete Lumbis wrote:
>
>> The biggest benefit you'll see with service instances over sub
>> interfaces is scalability. By abstracting out the 802.1q tag from the
>> forwarding action we don't necessarily have to burn platform resources
>> to make things happen.
>
> Yes, it works differently in the backend, but why must this be exposed to
> frontend? When configuration has no need to burn 802.1q tag, don't burn
> resources, do it intelligently in software, without user interaction.
>
>> For example, say you have 100 xconnects (L2VPN circuits) on a single
>> trunk interface. Traditionally you'd have to configure 100 sub
>> interfaces (or SVIs) which burns 100 VLANs on that platform. This
>>
>> if you have this same deployment with service instances you are merely
>> matching the tag on that port. You have 100 service instances
>> processing 100 802.1q tags (just like before) but now you haven't
>> burned any global VLAN resources.
>
> Right. And there is no technical reason, why when committing subinterface
> config with xconnect, it couldn't work exactly like it works today in EVC.
> Transparently, without user-interaction.
> So my question really is, what kinda benefits we do have in this double
> logical interface config structure? Is there something I can configure in
> both styles and might need to configure in both styles for single box for
> different requirement? As far as I know, no, I either need EVC or
> subinterface, which to mean translates single-behavioural need for UI.
>
> Seems not that hard 'do I have L3 AFI' yes -> create global VLAN. 'do I
> have L3 AFI' no -> handle locally.
>
> --
>   ++ytti
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/