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List of terms
backbone router
A router that has an interface to the backbone, including area border routers (ABR). A backbone router that has connections only to other backbone routers also functions as an internal router.
backplane
The printed circuit board into which control and function processors on a shelf are seated. The backplane serves two functions: distributes power to all processor cards on the shelf, and supports the bus that transports data and signaling between processor cards.
backplane bus
A
backplane control system (BCS)
The software system that manages the operation of the Nortel Multiservice Switch 15000 and Multiservice Switch 20000 fabrics. The BCS controls the fabrics on each processor card, allowing applications to send and receive frames over the backplane X and Y fabrics. The BCS also monitors the state of the fabrics to ensure that all cards can communicate. Lastly, the BCS allows the operator to monitor and test the fabrics.
backplane fabric
A
backplane file system (BFS)
The file system that enables a processor card to access files on either the active or standby control processor across the backplane.
backward congestion indication (BCI)
A bit in the Nortel Multiservice Switch packet header that indicates that packets travelling in the opposite direction on the connection are encountering congestion.
backward explicit congestion notification (BECN)
The bit in a frame relay header that indicates congestion in the path for the direction opposite to the direction in which the frame is flowing.
backward resource management cell (BRM)
Forward resource management cells that the ABR destination device turns around for delivery to the available bit rate source. See forward resource management cell (FRM) (page 54).
Nortel Multiservice Switch 7400/15000/20000
Terminology
PCR7.2 and up March 2006
Copyright © 2006, Nortel | Nortel Confidential |
