Networking: LAN, WAN and WLAN

Introduction to Networking

• A network involves two or more personal computers being linked together.
• Common network types include Local-Area Networks (LANs) and Wide-Area Networks (WANs).

LAN (Local Area Network)

• A LAN can span up to a 1 KM radius.
• It consists of computers and devices sharing a communication line or wireless link to a server.
• LANs connect computers and peripherals to a server within a limited geographic area.

WAN (Wide Area Network)

• A WAN's coverage has no limit.
• WANs connect different smaller networks, including LANs and metro area networks (MANs).
• With WAN, users in one location can communicate with other users in different locations.
• WANs can be implemented using a public transmission system or a private network.

WLAN (Wireless Local Area Network)

• WLANs wirelessly link two or more devices within a limited area.
• WLANs facilitate user mobility within a local coverage area while staying connected.
• Through a gateway, WLANs can provide internet connection.
• Modern WLANs follow IEEE 802.11 standards and are marketed under the Wi-Fi brand.

MAN (Metropolitan Area Network)

• A MAN interconnects users with computer resources in a geographic area larger than a LAN but smaller than a WAN.
• MANs interconnect networks within a city, potentially offering efficient WAN connections.
• Bridging several LANs through backbone lines is also considered a MAN.

CAN (Campus Area Network)

• A CAN consists of interconnected LANs within a limited geographical area.
• Networking equipment and transmission media in a CAN are primarily owned by the campus tenant or owner.

How Networks are Categorized

• Networks are classified based on topology, protocol, and architecture.
• Topology refers to the network's geometric arrangement (bus, ring, star).
• Protocol specifies the rules computers use to communicate (Ethernet, IBM's Token Ring).
• Architecture is either Peer-to-peer or client/server.

Peer-to-Peer Networking

• Peer-to-peer networks lack a central server; computers connect directly to share resources.
• Peer-to-peer setup is common in home configurations.
• Peer-to-peer setup is practical for small workgroups.

Client/Server Networking

• Client/server networks typically use an NT Domain Controller for computer log-in.
• The server provides services such as internet access, mail, file sharing, and security.
• Client/server setup is commonly used in corporate configurations.

Advantages of Peer to Peer Network

• Peer-to-peer networks are relatively inexpensive to build and maintain.
• No central configuration is required.
• Peer-to-peer networks are not dependent on a centralized system, connected computers function independently and failures don't disrupt other parts.
• Peer-to-peer networks are generally easy to set up, requiring only a hub or a switch.
• Peer-to-peer networks have good scalability
• Users manage their own systems, hence no specialized network administrator is needed.
• Each computer acts as both a server and a workstation, eliminating the need for a dedicated server.
• Peer-to-peer networks provide equal resource sharing among all users.

Disadvantages of Peer to Peer Networking

• P2P networking lacks centralization which makes locating files challenging.
• Performance degrades as the number of devices increases in P2P networks.
• Security for individual files are comparatively less in P2P networking.
• Remote access may lead to security vulnerabilities.
• Backup is difficult in P2P networks due to decentralized data.
• P2P networks are more prone to malware and virus attacks.
• P2P networks are often used for illegal content sharing, leading to potential legal issues.

Advantages of Client Server Network

• Client/server networks provide centralized control, beneficial for network administration.
• Client/server networks provide centralized data protection through access controls.
• Scalability is high in client/server networks.
• Client/server networks have streamlined file management due to central storage.
• All clients can access the system, irrespective of location or platform.

Disadvantages of Client Server Network

• Traffic congestion is a primary disadvantage of client/server networks.
• Client/server networks lack robustness, the entire network is disrupted by server failure.
• The cost of setting up and maintaining the server can be high.
• Client/server networks require non-stop maintenance and a specialized network manager.
• Not all server resources are accessible for client-side operations.