Cabletron Systems WPIM-DDS Management Manual - page 27
Wan Terms And Acronyms
WPIM-DDS Local Management Guide
A-3
HDLC
High-Level Data Link Control. A layer 2 (link layer)
full-duplex protocol derived from SDLC.
INV-HDLC
A form of zero suppression in which all zeros in the HDLC
packet are changed to ones and all ones are changed to zeros.
ISDN
Integrated Services Digital Network. Allows point-to-point
connections at 64 Kbps or 128 Kbps when necessary and
disconnects 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
effective 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. A protocol used in Frame Relay.
Allows the device to gather information about the DLCIs (Data
Link Connection 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
(internal) 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
signals 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.