perfsonar development work

[Freek Dijkstra <>]

Hi Giovanni,

Thank you for your answers. Let me clarify.

Giovanni Cesaroni wrote:

[...]
>> Basically, this describes a port with attached link,
>> "5004LE-asd001a_ome13-1-13-2", which is part of the end-to-end circuit
>> "CERN-TRIUMF-LHCOPN-001". Furthermore, this link is between nodes
>> NETHERLIGHT-AMS and CANARIE-CHCG1OME2.
>>
>> We have a few observations (or assumptions if you will). Can you confirm
>> if those are correct?
>>
[...]
>> - The node names are supposed to refer to device names, not to domain
>> names. Thus if the (name of a) node at a domain boundary chances, all
>> peering domains must chance their description as well.
>>    
> correct
> (in few cases the node name is the name of a PoP and not of a device, 
> but it doesn't change the meaning of your assumptions)

This is in fact unrelated to the multi-layer aspects, though we came
across a use case today. Right now, we really describe our network as a
single PoP. However, we rather like to describe it as individual devices
(using explicit Domain Links).

Your answer made us conclude that for a change in how we present our
topology (in this case from aggregated to non-aggregated), our peering
domains need to change their configuration. That is unfortunate.

>> - It is possible to describe multiple channels over a single physical
>> interface by describing each channel with a different logical name. For
>> example, assume that the above link between NETHERLIGHT-AMS and
>> CANARIE-CHCG1OME2 carries 2 channels, the link logical names could be
>> 5004LE-asd001a_ome13-1-13-2-channel-1 and
>> 5004LE-asd001a_ome13-1-13-2-channel-2. In this case, the peering domain
>> must also describe each channel with the same end-to-end path name
>> (globalName) and node names.
>>    
> mmm, I'd understand better the observation if you make some examples.
> What do you mean with channel?
> (If you mean for example a vlan, you could describe the vlan as an e2e...)

- Wavelength over a fiber
- VC-4 channel over an OC-192
- VLAN over an Ethernet link connection

(In ITU G.800 terminology: any forwarding port in a link port)


Regards,
Freek