Computer Networking Fundamentals and Architecture

Network Architectures and Technologies

According to the architecture: Arcnet, Ethernet, Token Ring, FDDI, ATM, ISDN, Frame Relay, DSL, and X.25.

Geographic Extent of Networks

• PAN (Personal Area Network): Home networks covering nearby areas within the same environment, such as the dependencies of a house (living room, bedroom, office, etc.). Example: Home Office.
• LAN (Local Area Network): Covers areas around local area networks within the same environment, such as offices, condominiums, schools, or a university campus.
• MAN (Metropolitan Area Network): Networks covering the metropolitan area of a large city or between nearby cities. Example: Speedy, Virtua.
• WAN (Wide Area Network): Long-distance networks connecting computers located in different cities, states, or countries. Example: The Internet.

Network Topologies

According to the network topology:

• Ring network
• Bus network
• Star network
• Mesh network
• Point-to-point network

Transmission Media and Connectivity

Wired Networks (Cable): Coaxial cable, twisted pair network cable, and fiber optics.

Wireless Networking: Infrared networks, microwave networks, and radio networks.

Network Roles: Servers, Clients, and Resources

• Server: Provides resources for the network. In a Peer-to-peer (P2P) network, there is no dedicated server; computers function as both clients and servers.
• Client: Also known as the user, this is the computer that uses the resources offered by the network.
• Resource: Anything that can be made available on the network, such as printers, disk drives, Internet access, files, and more.

The TCP/IP Protocol Suite

TCP/IP is a set of communication protocols between networked computers. Its name comes from two primary protocols: TCP (Transmission Control Protocol) and IP (Internet Protocol).

TCP/IP Layers

The Application Layer: This is the layer that most network programs use to communicate over a network with other programs. Processes that run in this layer are application-specific.

The Transport Layer: Protocols at this layer solve problems such as reliability (did the data reach its destination?) and integrity (did the data arrive in the correct order?). The suite of TCP/IP transport protocols also determines which application any given data is intended for.

The Network Layer (Internet or Internetworking): This layer is responsible for controlling traffic between networks in general. Its main functions include the routing of packets between source and destination.

IP Addressing and Routing

IP addressing is an important issue since it allows the numerous hosts and networks that form the Internet to communicate. There are two versions of IP; IPv4 is the current version.

Routing is performed by devices that execute routing procedures, better known as routing protocols.