Fundamentals of computer Networks

1.OSI (open System Interconnection) Open Systems Interconnect Reference Model. It is divided into application layer (SMTP), presentation layer, Transport layer (TCP), Network layer (IP), data connection layer, physical layer.

2.TCP/IP Network communication Protocol, Transmission Control Protocol TCP is a reliable connection-oriented Transport layer communication protocol based on Byte stream, the Internet is made up of tens of millions of computers, confirming that every computer on the network relies on the only IP that can recognize it.

3. Domain Name: is the name used on the Internet to identify the location of the network server, DNS is the abbreviation of the computer domain Name System, which consists of a parser and a domain name server.

4. Domain Name server: means the domain name and corresponding IP address of all hosts in the network, and a server that translates the domain name into the IP address function.

5. Network interconnection Devices: Hubs, switches, routers, modems, gateways, etc. only for network interconnection.

Physical layer, the data link layer with the device is: hub, switch: With the MAC address to determine the destination address of the forwarding data, where the exchanger can separate the conflict domain.

The network layer has the following devices: routers, which can separate conflict domains from broadcast domains.

Modem: Used to convert an analog signal to a digital signal.

Gateway: For the transport layer above.

Fundamentals of computer Networks