Clarify constraints on a Network Device's LLDP configuration

[garethsb]

LLDP (IEEE 802.1AB) seems to allow both Chassis ID and Port ID to use a number of sub-types.

In IS-06, the JSON schemas and documentation require that a Network Device's chassis_id MUST be the MAC address and the port_id MUST be the "Ethernet Interface information" or "the ifAlias".

However I think the spec would benefit from a clear statement that requires the LLDP emitted by the Network Device (switch) to correspond, identifying the relevant sub-types.

[garethsb]

References:

• IS-06 Endpoint schema says:
  • "chassis_id" is "as signalled in LLDP from this endpoint" (or null)
  • "port_id" is the "MAC address of the endpoint" (no mention of LLDP!)
  • "attached_network_device.chassis_id" is the "MAC address of the peer network device" (switch)
  • "attached_network_device.port_id" is the "ifAlias of the peer network device" (switch)
• IS-06 Network Device schema says:
  • "chassis_id" is "the MAC address of the network device" (switch)
  • "interfaces.port_id" is the "ifAlias of the network device" (switch), described as the "Ethernet Interface information" in the Network Links documentation
• IS-04 Node schema says:
  • "chassis_id" is "as signalled in LLDP" (or null)
  • "port_id" is "as signalled in LLDP or via ARP [and] must be a MAC address"
  • "attached_network_device.chassis_id" is the "Chassis ID [...] as signalled in LLDP"
  • "attached_network_device.port_id" is the "Port ID [...] as signalled in LLDP"

Given the means of discovery likely to be available to the Broadcast Controller and IS-04 Nodes, I think this implies that the IS-06 specification requires LLDP transmitted by network devices (switches) MUST use Chassis ID sub-type 4 "MAC address" and Port ID sub-type 1 "interface alias". If that were not true, the IS-06 schemas could not be met by transferring data from the IS-04 Node "attached_network_device" to the IS-06 Endpoint.

Is that so?

I'm not sure that the spec(s) require that IS-06 Endpoints (IS-04 Nodes) must transmit LLDP? If they do, they presumably MUST use Port ID sub-type 3 "MAC address" in order that the switch can match it to the Endpoint "port_id"?

[NEOAdvancedTechnology]

Gareth to make pull request for consensus position

[garethsb]

What's missing is top-level documentation in IS-06 that says IS-06 Network Device interfaces MUST transmit LLDP, signalling Chassis ID = MAC address and Port ID = ifAlias, and that an IS-06 Endpoint interface must transmit LLDP, signalling Port ID = MAC address (so far as I can see, there is no constraint in either spec on which LLDP Chassis ID subtype a Node/Endpoint should use?).

Unless I'm mistaken and IS-06 is usable without LLDP?

[NEOAdvancedTechnology]

Issue is solved.