M-R


MAC address

The unique identifier assigned to every network device when it is manufactured. The MAC is usually hard-coded and cannot be changed.

Media Access Control (MAC) layer

The protocol that defines how network adapters access the physical transmission medium of the network in the case of WLAN radio frequencies.

multipath signal interference

Multipath refers to a radio signal that because of obstructions or reflecting off of objects in the environment, splits into multiple signals that arrive at their destination at different times. This can cause problems as these different signals can cancel one another out and cause data loss.

Network Address Translation (NAT)

NAT translates internal network IP addresses into one or more public Internet IP addresses, allowing several computers on your network to share a common public IP address. NAT is how a broadband router shares your internet connection with the rest of the network. The router has a public Internet address and acts as a proxy between your network clients and the Internet. This protects your internal network and conserves the limited supply of public IP addresses.

Network Interface Card (NIC)

A network adapter, usually a PCI card, that allows a computer to connect to the local network, or Wi-Fi network in the case of a wireless NIC.

network latency

The amount of time it takes for data to make a round trip from one point to another on a network or across the Internet. Engineers often refer to latency as the round trip time (RTT). Many factors affect latency including network traffic levels, distance, signal loss, and interference.

network throughput

The amount of information that can be transferred between nodes on a network in a specific amount of time. Advertisers often advertise the potential throughput as a device’s speed. For example, 802.11g devices have an advertised maximum throughput of 54 Mbps, when in practice the actual network throughput seldom exceeds 30 Mbps.

Non-Line-of-Sight (NLOS)

A NLOS connection doesn’t require a line-of-site, obstruction-free signal path. NLOS signals can take different routes to their destination, including bouncing or reflecting off of environmental objects.

omnidirectional antenna

An antenna that radiates RF signals in all directions, rather than focusing them in one direction. This is the most common type of antenna and is usually the type that comes stock on most access points.

packet switching

The way that data is routed on a TCP/IP network (like the Internet). Computers divide data into smaller, individually addressed packets. Because each of these data packets contains a destination address, they can follow different paths to reach their destination. A packet-switched network uses network bandwidth more efficiently because users can send packets at the same time and share bandwidth. Routers direct each individually addressed packet to its proper destination.

Personal Digital Assistant (PDA)

A small handheld computer that stores personal information, and has productivity-enhancing applications. The best PDAs are as powerful as the desktop computers in use five to eight years ago. With the addition of a wireless adapter, most PDAs can connect to Wi-Fi or cellular networks.

piconet

An ad hoc network created when Bluetooth devices connect. A piconet can have up to seven Bluetooth devices, and piconets can connect to form larger scatternets.

Power over Ethernet (PoE)

A method of delivering power to Ethernet devices using Ethernet cable rather than an electrical cord. It’s possible to deliver power as well as data over Ethernet cable because it has two pairs of wires (4/5 and 7/8) that aren’t used in data transmission. PoE equipment uses these wires to supply power to PoE-compatible Ethernet equipment. Using PoE, you can install Ethernet equipment where it’s needed, rather than next to power outlets.

Radio Frequency (RF)

Electromagnetic frequencies higher than audio frequencies but lower than the frequencies of visible light. Wi-Fi devices use radio frequencies to communicate with each other.

radio frequency channel

A section, or slice, of a radio frequency band assigned for communication between two or more devices. Wi-Fi devices have several channels available for use in the 2.4 GHz range.

reversed polarity connectors

Also known as reversed gender connectors, RP connectors are coaxial plugs and jacks that have the center pin reversed, when compared to standard connectors of the same type.

RF interference

Radio frequency noise or competing transmissions in the same frequency band as a WLAN. RF interference can prevent normal operation of a wireless network.

Roundtrip Time (RTT)

A term used interchangeably with latency to describe the amount of time it takes for data to make a round trip between nodes on a network.

(router)

A device that forwards data traffic between networks. A broadband router forwards data between the Internet and your network clients (see network address translation). Some routers also include an integrated firewall to protect your network from unauthorized access and attack.




Caution. Wireless Networking. Preventing a Data Disaster
Caution! Wireless Networking: Preventing a Data Disaster
ISBN: 076457213X
EAN: 2147483647
Year: 2003
Pages: 145

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