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ISAKMP - Internet Security Association and Key Manangement Protocol. The basis for IKE.
ISP - Internet Service Provider. An ISP is a business that provides connectivity to the
Internet for individuals and other businesses or organizations.
JPEG – Joint Photographic Experts Group. JPEG is a standard for compressing still images
and it provides compression with ratios up to 100:1. File extensions are .JPG or .JPEG.
LAN - A communications network that serves users within a confined geographical area. It is
made up of servers, workstations, a network operating system and a communications link.
Servers are high-speed machines that hold programs and data shared by network users. The
workstations (clients) are the users' personal computers, which perform stand-alone
processing and access the network servers as required.
Diskless and floppy-only workstations are sometimes used, which retrieve all software and
data from the server. Increasingly, "thin client" network computers (NCs) and Windows
terminals are also used. A printer can be attached locally to a workstation or to a server and
be shared by network users. Small LANs can allow certain workstations to function as a
server, allowing users access to data on another user's machine. These peer-to-peer
networks are often simpler to install and manage, but dedicated servers provide better
performance and can handle higher transaction volume. Multiple servers are used in large
networks.
The message transfer is managed by a transport protocol such as TCP/IP and NetBEUI. The
physical transmission of data is performed by the access method (Ethernet, Token Ring,
etc.), which is implemented in the network adapters that are plugged into the machines. The
actual communications path is the cable (twisted pair, coax, optical fiber) that interconnects
each network adapter.
MAC Address - MAC (Media Access Control) A MAC address is the hardware address of a
device connected to a network.
MDI / MDI-X - Medium Dependent Interface - Also called an "uplink port," it is a port on a
network hub or switch used to connect to other hubs or switches without requiring a
crossover cable. The MDI port does not cross the transmit and receive lines, which is done by
the regular ports (MDI-X ports) that connect to end stations. The MDI port connects to the
MDI-X port on the other device. There are typically one or two ports on a device that can be
toggled between MDI (not crossed) and MDI-X (crossed).
Medium Dependent Interface – X (crossed) - A port on a network hub or switch that crosses
the transmit lines coming in to the receive lines going out.
MP3 – MPEG Audio Layer 3. This is an audio compression technology that is included in the
MPEG-1 and -2 specifications. MP3 encoding can allow you to compress CD-quality sound by
a factor of 12.
MPEG – Moving Pictures Experts Group. MPEG is a standard for compressing video. MPEG-1
can provide resolution of 352x240 at 30 frames/second (fps) with 24-bit color and CD-
quality sound. MPEG-2 can provide resolution of 704x480. MPEG uses the same intraframe
coding as JPEG for individual frames, but also uses interframe coding which can help to
further compress the video data, thereby reducing the overall size of the video.
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