CCNA Cisco Certified Network Associate Study Guide - FTP Server

Glossary 685
LANE LAN emulation: The technology that allows an ATM network to
operate as a LAN backbone. To do so, the ATM network is required to provide
multicast and broadcast support, address mapping (MAC-to-ATM),
SVC management, in addition to an operable packet format. Additionally,
LANE defines Ethernet and Token Ring ELANs. See also: ELAN.
LAN switch A high-speed, multiple-interface transparent bridging mechanism,
transmitting packets between segments of data links, usually referred
to specifically as an Ethernet switch. LAN switches transfer traffic based
on MAC addresses. Multilayer switches are a type of high-speed, specialpurpose,
hardware-based router. See also: multilayer switch, and store-andforward
packet switching.
LAPB Link Accessed Procedure, Balanced: A bit-oriented Data-Link layer
protocol that is part of the X.25 stack and has its origin in SDLC. See also:
SDLC and X.25.
LAPD Link Access Procedure on the D channel. The ISDN Data-Link layer
protocol used specifically for the D channel and defined by ITU-T Recommendations
Q.920 and Q.921. LAPD evolved from LAPB and is created to
comply with the signaling requirements of ISDN basic access.
latency Broadly, the time it takes a data packet to get from one location to
another. In specific networking contexts, it can mean either 1) the time elapsed
(delay) between the execution of a request for access to a network by a device
and the time the mechanism actually is permitted transmission, or 2) the time
elapsed between when a mechanism receives a frame and the time that frame
is forwarded out of the destination port.
Layer-3 switch See also: multilayer switch.
layered architecture Industry standard way of creating applications to
work on a network. Layered architecture allows the application developer to
make changes in only one layer instead of the whole program.
LCP Link Control Protocol: The protocol designed to establish, configure,
and test data link connections for use by PPP. See also: PPP.
leaky bucket An analogy for the basic cell rate algorithm (GCRA) used in
ATM networks for checking the conformance of cell flows from a user or
network. The bucket’s “hole” is understood to be the prolonged rate at
which cells can be accommodated, and the “depth” is the tolerance for cell
bursts over a certain time period.