Computer Networks: Crash Course Computer Science #28

LAN

(Local Area Network) A computer network limited to the immediate area usually the same building or floor of a building or a school campus.

MAC address

A Media Access Control address is a hardware address that uniquely identifies each node on a network.

Internet Protocol (IP)

A communication standard that enables computers to route communications traffic from one network to another as needed.

ARPANET

A computer network developed by the Advanced Research Project Agency (now the Defense Advanced Research Projects Agency) in the 1960s and 1970s as a means of communication between research laboratories and universities. It was the predecessor to the Internet.

Network Router

A device found at each intersection on the Internet backbone that examines the IP address of incoming data, and forwards the data towards its destination.

IP address

A number that uniquely identifies each computer or device connected to the Internet.

Message Switching

A telecommunications methodology that controls traffic in which a complete message is sent to a concentration point and stored until the communications path is established.

exponential back-off

Backing off behavior using an exponentially growing wait time.

BGP

Border Gateway Protocol A core routing protocol that bases routing decisions on the network path and rules.

CSMA

Carrier Sense Multiple Access--A method used by Ethernet networks to allow shared usage of a baseband network and avoid collisions.

ICMP

Internet Control Message Protocol A TCP/IP protocol that is used by devices to communicate updates or error information to other devices.

hop count

The counter associated with a packet as it moves from node to node within a wide area network. Every time the packet moves to the next node, the hop count is increased/decreased by 1.

Hop Limit

The number of times that an IPv6 packet can be forwarded by routers on the network; similar to the TTL field in IPv4 packets.

Collision Domain

The portion of an Ethernet network in which collisions could occur if two nodes transmit data at the same time.

TCP/IP

Transmission Control Protocol/Internet Protocol. Protocol that connects computers to the Internet. Tells computers how to exchange information over the Internet.

collision

When network traffic increases, the probability that two computers will attempt to write data at the same time also increases. When that happens the data gets all gobbled up, like two people trying to talk on the phone at the same time.

circuit switching

a dedicated connection is formed between two points and the connection remains active for the duration of the transmission

Packet Switching

a mode of data transmission in which a message is broken into a number of parts that are sent independently, over whatever route is optimum for each packet, and reassembled at the destination.

Ethernet

a system for connecting a number of computer systems to form a local area network, with protocols to control the passing of information and to avoid simultaneous transmission by two or more systems.

The bigger the networks the more likely that there are

multiple paths to get data from one location to another.

Network Switch

network controller which connects network devices and allows effective communication between these devices

bandwidth

the sense in multiple access and the rate at which the carrier and transmit data