PBT

Metro Ethernet has been going through some important changes as PBB-TE (PBT) has begun to take hold in the industry. The main arguments for PBT are based on lower cost, revolving around the technology's simplicity and capabilities for management of large-scale systems.

Because of PBT's deterministic approach, management of nodes becomes straightforward. Traffic shaping, granular provisioning, and fault identification are all built into the system. Furthermore, the intrinsic structure of the MAC-in-MAC addressing scheme mean that it is straightforward to create additional nodes and sub-nodes, further scaling the network.

The next natural step for PBT is further extension out to the edge. Currently, when vendors talk about PBT to the edge, they are referring to the network edge, that is, the first aggregation point. However, PBT can naturally have applications further out, at the actual customer premises. For example, at a campus or multi-tenant building, PBT can be used to provision each office separately, or again, to provision separate services within the office.

Telrad has developed CPE units that bring PBT to the edge, as shown in the following diagram.

Bringing PBT to the customer edge exponentially increases the number of VLANs that can be provided at multi-tenant sites, as well as at base stations and other types of end-user premises. Once the operator provides such an extensive solution, routing, fault management, and provisioning become much more cost-effective.

Operators can measure exactly what each individual customer is getting, and charge for guaranteed SLAs accordingly. This provides increased sources of income, and a higher level of customer satisfaction.

Using this configuration, operators can reduce the costs of support and service because of granular fault management.