Cisco BPX-BXM-155-8DX Installation And Configuration Manual page 623

W
A network of transmission circuits generally spanning a large region or territory for transmission of
WAN (Wide Area
Network) voice and data between widespread end users. An IGX/BPX network is an example of a WAN.
X
X.21 A CCITT standard for data interfaces transmitting at rates up to approximately 2 Mbps.
A commonly-used standard that defines the protocol for low-speed data packet networks.
X.25
A simple communications protocol for controlling the flow of data from one device to another. An
XON/XOFF
XON sent from a receiving device indicates it is ready to accept data and the transmitting device may
begin to output data. An XOFF from the receiving device indicates that it can no longer store any more
data and the transmitting device should temporarily cease transmitting.
Y
A short adapter cable forming an electrical branch (thus the term Y) for connecting a single customer
YY-cable(s)
data or trunk connection to two identical back cards to provide hardware redundancy on the IGX
switch.
A redundancy type used in the switch when a 1:1 card redundancy is implemented using a split or
Y-cable redundancy
Y-cable for the data connection between the user device and the primary and standby interface card.
A digital trunk conforming to the Japanese "Y" circuit standard, for use as a packet line. Similar to
Y1
T1, it operates at 1.544 Mbps.
Another name for remote alarm as the remote alarm lamp on digital transmission equipment is always
yellow alarm
yellow in color.
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Cisco BPX 8600 Series Installation and Configuration
Glossary
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