Back to WaMu banks on MPLS

1. Metropolitan-area network: Each of WaMu's 3,000 locations feed LAN traffic into one of multiple MANs. Connectivity from MAN to MAN is achieved using dense wave division multiplexing and SONET ring technologies.

2. Supercore: A supercore provides a gateway for handoff of MAN traffic into the wide-area MPLS network. Supercores connect to the MCI network for primary service via two SONET OC-3 (155M bit/sec) trunks and to back-up carrier AT&T over a single OC-3 circuit. With each of these consolidated nodes, WaMu can partition the MPLS/WAN backbone to make upgrades, to contain security breaches, and to activate new sites without affecting overall performance of MPLS and desktop traffic.

3. MPLS/WAN backbone: MCI-based MPLS network handles supercore-aggregated traffic and consists of nine nodes that collapse into a three-node backbone.

4. Access layer for business partners. WaMu provides MPLS partners AT&T, Cisco, Juniper and MCI access to back-office systems running administrative, billing and management applications. This layer is firewall-protected.

5. Disaster-recovery layer. Details largely undisclosed, but this layer provides excess capacity, backup and storage in the event of network failure.

6. Dial back-up layer/ISDN: Provides a connectivity option should the MPLS network or MCI's infrastructure as a whole go down.