Here the data will be set up for gathering or sampling and then either saved or sent at a certain interval to the management and control system. The second is data generated by instrumentation and appliances used to “measure” the network. These data may be sent proactively to the measurement and control system or they may be periodically measured, then collected through sampling or querying the network equipment directly. The first is data generated by the network components themselves, as part of operating and providing services.

Network telemetry is performance data provided by two distinct sources in the network: ▪

Consider this integrated SUPM then, as a set of interrelated and connected subsystems providing services to customers and requiring measurement and management, through the use of network telemetry. Think of the network-including the FTTx access component (OLT and ONTs), the upstream components for transport, aggregation switches and routers, and the services integration equipment-as the entire integrated system under performance management. For the hybrid (C-VLAN with M-VLAN) model, the Ethernet switch must be able to pop/push tags onto C-VLAN traffic while not modifying the M-VLAN packets. VLAN stacking is not needed for S-VLANs or on the M-VLAN. The reverse process happens for upstream traffic. For downstream traffic, the Ethernet switch uses the outer tag to determine which port to forward the traffic to and will pop this tag before forwarding the traffic. In the last model, the traffic from the BSR to the switch includes two VLAN tags: an outer tag identifying the destination MSAN, and an inner tag identifying the subscriber on that MSAN. If there may be more than 4,095 subscribers per BSR port, then VLAN stacking (IEEE 802.1ad, also known as Q-in-Q) must be used.

If there are (and always will be) less than 4,095 subscribers connected to a single BSR port, then the aggregation switch can transparently pass all VLANs. When using an aggregation switch with a C-VLAN topology, there are two situations to consider: 1. The 12-bit VLAN identifier supports up to 4,095 subscribers.

Tor switch vs core switch