Nortel Meridian

Nortel Meridian is a private branch exchange telephone switching system. It provides advanced voice features, data connectivity, LAN communications, computer telephony integration (CTI), and information services for communication applications ranging from 60 to 80,000 lines.

History

Exploratory development on digital technology, common for the SL-1 (PBX) and the DMS (public switch) product lines, began in 1969 at Northern Telecom, while R&D activities related to the SL-1 started in June 1973. SL stands for Stored Logic.

It was introduced by Northern Telecom in December 1975, with an original capacity from 100 to 7,600 lines, and became the first fully digital PBX announced on the global market aimed at the smaller PBX market. In the early 1970s, most PBXs were either electromechanical (e.g. cross-bar) or based on a hybrid technology (e.g. switching matrix made from a two-dimensional array of contacts but control performed by an electronic logic). For this reason, the SL-1 enjoyed a great success on the enterprise market both in North-America and globally.

Silver Line (MBTA)

The Silver Line is the bus rapid transit (BRT) system of the Massachusetts Bay Transportation Authority (MBTA). It currently operates four routes in two sections that were built in separate phases.

The first section has two routes from Dudley Square in Roxbury, mostly via Washington Street, to Boston's Downtown Crossing (SL5) and South Station (SL4), using articulated buses operating in reserved lanes. The second section runs from South Station Under to South Boston (SL2) and to Logan Airport in East Boston (SL1). It runs dual-mode buses, partly in a dedicated bus tunnel and partly on shared roadway, including surface streets, the Ted Williams Tunnel, and airport roads. Riders can transfer between the sections and to other lines at South Station; transfers there between SL1, SL2, and the Red Line—but not SL4—are within fare control. At South Station, however, a transfer from SL1, SL2, and the Red Line to SL4 (and vice versa) can be made by walking alongside streets.

Speed and schedule performance have disappointed some transit advocates and the Silver Line routes fall far short of the minimum BRT Standard promulgated by the Institute for Transportation and Development Policy (ITDP). Some sections have an exclusive right-of-way, but other sections are bogged down by street running in congested mixed traffic. As of September 2014, a contract has been awarded for the first phase of an extension to Chelsea, Massachusetts, largely in reserved right-of-way; other extensions of the Silver Line are being studied as well.