Pittsburgh, Pennsylvania-based firm Fore Systems Inc has already delivered the first results of its agreement with Northern Telecom Ltd (CI No 2,599) with a range of new T1 and E1 – 1.544Mbps and 2.048Mbps and JT2 – 6.312Mbps – wide area Asynchronous Transfer Mode interfaces. They are for use in the company’s ForeRunner ASX-200 Asynchronous Mode family of switches, and designed to connect users with wide area network carrier services. They incorporate the ability to pass timing information from the carrier network to locally-attached Asynchronous Transfer devices in order to support constant bit rate traffic such as voice and video, says Fore. To address bandwidth management, Fore has incorporated ForeThought Bandwidth Management technology into the modules: this is said to support all traffic classes, including constant, variable, available and unspecified bit rates. Fore has chosen to manage buffers using per-virtual circuit queuing, rather than the more common First-In, First-Out system. Fore says its approach, which creates a dedicated queue for each virtual circuit rather than buffering all connections destined for the same output port in a single queue as with First-In, First-Out, eliminates intolerable cell delays, as each connection can be serviced independently. Also featured are Smart Buffers that are claimed to have the largest per-port capacity available (13,312 cells) and dynamically allocate space according to service level requirements. Two Packet Level Discard techniques have been included, Partial Packet Discard and Early Packet Discard, while the company has also implemented its existing explicit forward congestion indicator, and dual-leaky bucket per-virtual circuit queuing. The modules come in two- and six-port configurations, at prices from $2,500. Fore says it is also enhancing its existing high-speed DS-3 – 45Mbps, E-3 – 34Mbps, and OC-3c/STM-1 – 155Mbps – interfaces with additional but unspecified wide area network capabilities.
