But unlike fault-tolerant Sonet, RPR will use both signals to carry traffic. If one signal is cut, all customers will be switched over to the remaining signal, meaning that their bandwidth drops but their data sessions are maintained. More important, since RPR is a higher-level protocol than Sonet, providers won't need to retrofit their existing Sonet networks to deploy it. Existing services will still operate normally, since Sonet equipment treats resilient packet rings like ordinary Ethernet. The difference is inside the resilient packet ring portion of the network, which uses both the active and the backup signal in the ring to send traffic.
Service providers are more than ready for the technology, if it delivers as promised.
The provider has turned to gigabit Ethernet to link customers to the Internet. It can be transported on top of a Sonet ring to add fault tolerance, but this bumps the costs back up. If something happens to break the connection, the traffic is redirected around the ring, so the customer doesn't experience an interruption, says IntelliSpace chief technology officer Carlo Lalomia. An actual standard implementation for the protocol is still in its very earliest stages of development. At least in these early stages, participants in the IEEE working group say the emphasis is on progress, not politics.