Fujitsu Network Communications has added both high-order and low-order virtual concatenation (VCAT) to its FLASHWAVE 4100 optical access platform. Support for both high-order and low-order VCAT enables carriers to transport next-generation services across existing SONET networks more efficiently. The FLASHWAVE 4100 Multi-Service Provisioning Platform (MSPP) supports the delivery of Ethernet over SONET (EoS) through Ethernet/Fast Ethernet (10/100Base-T) or Gigabit Ethernet interfaces.
VCAT allows the same full wire speed Gigabit Ethernet circuit that previously required an STS-24c to be mapped into seven virtually concatenated STS-3c envelopes (STS-3c-7v). VCAT allows the same full wire speed Gigabit Ethernet circuit that previously required an STS-24c to be mapped into seven virtually concatenated STS-3c envelopes (STS-3c-7v). Fractional, tiered-rate services may also be provided by using up to 12 concatenated STS-1 channels or up to eight concatenated STS-3c payloads. End users may request a partial rate, tiered service with an actual throughput composed of multiple STS-1 (51.84 Mbps) or STS-3c (155.52 Mbps) concatenated channels.
Fujitsu said its FLASHWAVE 4100 platform is also one of the first systems to support low-order VCAT for efficient mapping of Ethernet and Fast Ethernet circuits into virtually concatenated VT1.5 (1.728 Mbps) payloads. Low-order VCAT allows each Ethernet frame to be spread across all available VT1.5 channels on a byte-by-byte basis, as opposed to the frame-by-frame scheme of Multi-Link Point-to-Point Protocol (MLPPP) technology. When compared to MLPPP, low-order VCAT offers a reduction in the time required to transmit an entire Ethernet frame proportional to the number of VT1.5 channels provisioned. Low-order VCAT also offers greatly reduced latency and higher effective bandwidth when an acknowledgement-based protocol such as TCP/IP is used for transport and flow control.
In addition, new management capabilities allow FLASHWAVE 4100 nodes on the endpoints of an Ethernet circuit to monitor the delay of various routes across the network. http://us.fujitsu.com
