USN Architecture: Separate data and control planes
Two-layered architecture of USN enables flexibel dedicated channels to be provisioned in the data plane using a secure control plane:
USN data plane consists of two OC192 connections switched in the core by Ciena CDCI and at the edges by Force10 E300 as as shown below. SONET channels can be provisioned between CDCIs at OC3 (150Mps) resolution with maximum OC192 (9.6Gbps) capacity.
USN Data Plane Node
USN data plane node consitsts of hosts in addition to core and edge switches.
USN Control Plane
Since there is no expectation of continuity of data plane, control plane was implemented out-of-band over Internet connections. However, control plane traffic is supported over encrypted and authenticated tunnels using Netscreen NS-50 and NS-5.