Switch system comprising two switch fabrics

摘要

A switching system having at least two switch fabrics. Each fabric has a switch core and a set of SCAL (Switch Core Access Layer) receive and transmit elements. The switch cores are preferably located in the same physical area but the SCALs may be distributed in different physical areas. Port Adapters distributed at different physical areas are connected to the switch fabrics via a particular SCAL element so that each switch core can receive cells from any port adapter and conversely any port adapter may receive data from either switch core. Control logic assigns a particular switch core to one port adapter for normal operations while reserving the other switch core for use when the first core is out of service. Each switch core has a mask mechanism which uses the value in a mask register to alter a bitmap value which controls the routing process. The mask registers in the two switch cores are loaded with complementary values.