Cabletron Systems WPIM-SY Management Manual - page 38
APPENDIX B: WAN TERMS AND ACRONYMS
WPIM-SY LOCAL MANAGEMENT GUIDE
B-3
ISDN
Integrated Services Digital Network. Allows point-to-point
connections at 64 Kbps or 128 Kbps when necessary and dis-
connects the line when not in use. With this service the user
only pays for the time connected.
JBZS
Jam Bit-Zero Suppression, a form of zero suppression that
places a one in the seventh bit of a timeslot. Reduces the effec-
tive throughput to 56 Kbps.
LEX
LAN Extender, a Cisco Systems protocol used to internetwork
a host-based router with a remote switch.
LMP
Link Management Protocol, used in Frame Relay. Allows the
device to gather information about the DLCIs (Data Link Con-
nection Identifiers) See T1.617-D, Q.933-A.
Local Timing
Timing for digital transmission circuit is internally generated
by a source within the equipment. Usually used for short haul
private lines. In this case one CSU must be set for Local (inter-
nal) timing and the CSU at the other end of the line must be set
for Loop (recovered) timing to create a master-slave situation.
Loop Timing
Timing for digital transmission circuit is recovered from the
received data, not generated internally by a source within the
equipment. This is the typical situation when using public
lines.
MIM
Media Interface Module, Cabletron Systems products designed
to fit in a Multi Media Access Center (MMAC) hub.
MUX
Multiplexer, an electronic device that allows two or more sig-
nals to pass over one communications circuit.
PPP
Point-to-Point Protocol, provides a method for transmitting
datagrams over serial point-to-point links.
PRI
Primary Rate Interface, an ISDN service providing 23 “B”
(Bearer) channels of 64 Kbps and one 64 Kbps “D” (Data)
channel for signaling and control.
PVC
Permanent Virtual Circuit, a virtual circuit that provides the
equivalent of a dedicated private line service.
Q.933-A
Q.933 Annex A, an ITU link management protocol specifica-
tion used in Frame Relay.