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 By Technology:

Major types of wireless networks include:

• Phone-line networking technology commonly referred to as HomePNA, is based on the specifications developed by the Home Phone Networking Alliance (HPNA), and uses the telephone jacks to connect the computers to the network.  In HomePNA, voice and data travel on the same wires without interfering with each other.

• Optical networking  is comprised  fiber optic cabling, which transmits data as electronic pulses. Technologies based on communication standard such as SONET/SDH, and protocol FDDI.

• Grid system. This is a type of parallel and distributed system that enables the sharing, selection, and aggregation of geographically distributed "autonomous" resources dynamically at runtime depending on their availability, capability, performance, cost, and users' quality-of-service requirements.  (see: www.ibm.com).

• The Virtual Private Network (VPN) is a logical, secured network that connect users together across the Internet. This  technology  allows users to connect  without purchasing expensive equipment and services.

• Intranet is the Internet technology used for  LAN.

By Communication Standards and Protocols

Standards, legitimated by Standard Organizations (as ANSI, IEEE, ISO, etc.), are imbedded in most of the components that can  be used in network. There are standards for wire, for the connectors on the ends of the wire, for voltages on the wires, for how the client stations will "talk" using those voltages, and so on. But amid these standards there are most  important standards for communications in the network on the physical and data link layers (according to the 7-Layer OSI Model.) -communication standards.

Here are several examples of communication standards:

• Synchronous Optical Network (SONET) is standard for fiber optic networks.

• Synchronous Digital Hierarchy (SDH) is another  standard for fiber optic communications, based upon a transfer rate of 51.84 megabits per second.

• Asynchronous Transfer Mode (ATM) is a high-sped networking standard designed to support both voice and data communications.

• IEEE 802.11, Bluetooth for WLAN. These are  wireless data networking standards.

• HPNA 2.0 is the standard for Phone-line networking technology

Protocols: A protocol is a standard for devices communication. Protocols can be broken down into layers.  A group of protocols that work together is called a protocol suite.  Protocol specifies a common set of rules and signals for the computers communication on the network.  Here are those  in the common use:

• TCP/IP  ( Transmission Control Protocol / Internet Protocol):  This protocol is used as the basis for the internet,

• IPX/SPX (Internetwork Packet eXchange/Sequenced Packet eXchange):  IPX is like an optimized TCP/IP, it allows quicker access over the network than TCP/IP,

• NetBEUI : This protocol is designed for small LANs,

• AppleTalk:   A set of communication protocols that define networking on an AppleShare network. This protocol is used for mapping a device's physical hardware address to a temporary Appletalk network-assigned address in Macintosh computer LANs,

• FDDI (Fiber Distributed Data Interface) is a protocol for transmitting data over optical networks, standardized by The American National Standards Institute (ANSI),

• The Token Ring protocol is a popular network protocol for data transmission. IBM's version of the Token Ring protocol has been accepted as the standard by the Institute of Electrical and Electronic Engineers (IEEE).

By Topology 

Topology specifies the geometric arrangement of the network. Common topologies are a bus, ring, star, tree, mesh, hybrid . A bus topology means that each computer on the network is attached to a common central cable, called a bus or backbone.   A ring topology means that each computer is connected to two close ones, and they arranged in a shape of ring. A star topology means all computers on the network are connected to a central hub.  A tree topology resembles a tree with branches ending  computers as leafs. A full mesh topology provides a point-to-point connection between every computer on the network. Hybrid topologies are a mixture of other topologies on the network.

These are  the two major types of the classical network architecture: Peer-to-peer (P2P) or Client/server. In a Peer-to-Peer networking configuration, there is no server, and computers simply connect with each other  to share files, peripherals, or Internet access. This is most commonly found in home configurations, and is only practical for workgroups of a dozen or less computers. In a client/server network, one computer, that called a server (rest computers are clients), able to provide various services, including centrally routed  file sharing,  peripherals  access, Internet Access, e- mail, as well as ensuring security across the network. This is most commonly found in corporate configurations, where network security is essential.