L2F

Layer Two Forwarding, is a Cisco tunneling protocol that uses virtual dial-up networks for secure data packet transport.

Lag

A period of time in which it seems a computer is not connecting to a requested Website. It is also a term used in connection with IRC. The lag is the time it takes for a message to travel from the user's server to the Net. If it is bad, then it maybe hard to keep up with the conversation.

LAMP

Short for Linux, Apache, MySQL and PHP. An open-source Web development platform that uses Linux as the operating system, Apache as the Web server, MySQL as the RDBMS and PHP as the object-oriented scripting language. Perl or Python is often substituted for PHP. LAMP has become a de facto development standard.

LAN

Local Area Network. A network of two or more computers usually spanning a relatively small geographical area. May be connected to other LANs to form a WAN.

Landgrab

The mad rush for domain names and the establishment of brands at the start of the dot-com boom.

LAP-B

Link Access Procedure-Balanced. A protocol that is a subset of HDLC.

LAP-D

Link Access Procedure D-channel. A protocol that is a subset of HDLC.

LAT

Local Area Transport, a DEC proprietary Ethernet protocol for connecting terminals to a LAN. Connections are typically between a DEC terminal server and a VAX.

Latency

The time it takes for a packet to arrive at its destination.

LAWN

Local Area Wireless Network.

LBA

Logical Block Addressing, a method used with SCSI and IDE disk drives to translate the cylinder, head and sector specifications of the drive into addresses that can be used by an enhanced BIOS. LBA is used with drive's that are larger than 528 Mb.

LCD

Liquid Crystal Display, a type of display used in watches and many portable computers.

LCP

Link Control Protocol, a protocol that is part of the PPP. In PPP communications, both the sending and receiving devices send out LCP packets to determine specific information that will be required for the data transmission.

LDAP

Lightweight Directory Access Protocol, a set of protocols for accessing information directories. LDAP is based on the standards contained within the X.500 standard, but is significantly simpler. And unlike X.500, LDAP supports TCP/IP, which is necessary for any type of Internet access.

LEC

(1) Local Exchange Carrier. Is the term for a public telephone company in the U.S. that provides the local service.

(2) LAN Emulation Client. Software providing the emulation of the link layer interface that allows the operation and communication of all higher-level protocols and applications to continue.

LED

Light-Emitting Diode, is a semiconductor light source that emits light when current flows through it.

Leet

Leet, is a system of modified spellings used primarily on the Internet. It often uses character replacements in ways that play on the similarity of their glyphs via reflection or other resemblance.

Lidar

Light Detection and Ranging, is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth.

Link

See hyperlink.

Link Farming

(1) The process of exchanging reciprocal link with Web sites in order to increase search engine optimization (SEO). The idea behind link farming is to increase the number of sites that link to yours because search engines such as Google rank sites according to, among other things, the quality and quantity of sites that link to yours. In theory, the more sites that link to yours, the higher your ranking in the search engine results will be because the more links indicate a higher level of popularity among users of the Internet. However, search engines such as Google consider link farming as a form of spam and have been implementing procedures to banish sites that participate in link farming, so the term link farming has garnered negative connotations across the Internet. A link farm is a Web page that is nothing more than a page of links to other sites.

(2) In UNIX systems, a link farm is a directory tree containing links to files in a master directory tree of files.

Linux

A freely-distributable open source implementation of UNIX that runs on a number of hardware platforms, including Intel and Motorola microprocessors. Another popular, free version of UNIX that runs on Intel microprocessors is FreeBSD.

Liquid

A webpage whose content is designed to fit no matter the display resolution or window size of a user's browser.

LISP

LISP is an object-oriented programming language.

LLC

Logical Link Control, a sublayer of the Data Link Layer of the OSI 7 layer model. Provides an interface between the MAC sublayer and the Network Layer.

LLVM

Low Level Virtual Machine, compiler infrastructure project is a "collection of modular and reusable compiler and toolchain technologies" used to develop compiler front ends and back ends.

LMHOSTS

A static file containing NetBIOS name to TCP/IP address mappings.

Load

(1) To install. For example, to load a disk means to mount it in a disk drive.

(2) To copy a program from a storage device into memory. Every program must be loaded into memory before it can be executed. Usually the loading process is performed invisibly by a part of the operating system called the loader. You simply enter the name of the program you want to run, and the operating system loads it and executes it for you.

(3) In programming, load means to copy data from main memory into a data register.

(4) In networking, load refers to the amount of data (traffic) being carried by the network.

Logic Bomb

A logic bomb is a piece of code intentionally inserted into a software system that will set off a malicious function when specified conditions are met.

LSA

(1) Large Scale Array.

(2) Linux Standards Association.

LUN

Logical Unit Number, is a number used to identify a logical unit, which is a device addressed by the SCSI protocol or SAN protocols which encapsulate SCSI, such as Fibre Channel or iSCSI.

Lurker

A visitor to a newsgroup or chat room who simply views activity without taking part.