LAN & WAN | IGCSE Information and Communication Technology Preparation - Year 11 PDF Download

LAN

• Limited Geographic Scope: LANs typically cover a small geographic area, often confined within a single building or a small campus environment.
• Infrastructure Components: LANs are constructed using hubs and/or switches to interconnect multiple devices within the network. These devices facilitate communication and data transfer among connected devices.
• Connection to External Networks: A common configuration involves connecting a hub or switch to a router. The router serves as a gateway, enabling connectivity between the LAN and external networks such as the internet. This allows LAN users to access resources and services beyond the local network.
• Localized Resource Sharing: LANs facilitate resource sharing among connected devices, allowing users to share files, printers, and other network resources within the local network environment.
• High-Speed Data Transfer: LANs typically offer high-speed data transfer rates, making them suitable for applications requiring rapid data exchange within the local network.

Advantages of a Local Area Network (LAN)

• Centralised Management: A LAN enables centralized management of updates, backups, and software installations. For example, a company's IT department can efficiently update software across all connected devices from a central location.
• Enhanced Security: Security features like firewalls and antivirus software can be implemented on a LAN to prevent unauthorized access to data. This ensures that sensitive information remains protected within the network.
• File Sharing and Collaboration: Users within a LAN can easily share resources such as printers and files, fostering collaboration among team members. For instance, colleagues can work on shared documents simultaneously, enhancing productivity.

Disadvantages of Local Area Networks (LAN)

• If hardware malfunctions, the LAN may cease to operate effectively or entirely.
• LANs are more susceptible to cyber-attacks compared to individual computers operating in isolation.
• Accessing data and peripherals over a LAN can be sluggish due to network congestion.
• Maintenance demands are high for LAN networks to ensure current software, upgrades, and backups, incurring potentially significant costs.

WAN

• Wireless Connectivity: WLANs are Local Area Networks (LANs) that enable devices to connect wirelessly, eliminating the need for physical cables.
• Wireless Access Points (WAPs): Wireless Access Points serve as connectors between wireless devices and an existing wired network infrastructure. They facilitate wireless connectivity by providing access to the network.
• Spread Spectrum Technology: Wireless Access Points utilize spread spectrum technology, offering a range of approximately 30 to 50 meters. This technology contrasts with Infrared, which has a much shorter range of around 3 meters.
• Practicality and Convenience: WLANs are preferred in situations where using physical cables is impractical or where devices lack Ethernet ports. This makes them suitable for environments where mobility and flexibility are important.
• Device Compatibility: WLANs support a wide range of devices, including smartphones, laptops, tablets, and other wireless-enabled devices. This versatility makes WLANs popular in public areas such as shopping malls, airports, and cafes, where users expect wireless connectivity.

Advantages of Wireless Local Area Networks (WLAN)

• Mobility: Wireless LANs (WLANs) offer users the freedom to connect from anywhere within the range of a Wireless Access Point (WAP) without the constraints of additional hardware or wiring. For example, in a university campus with WLAN coverage, students can move between buildings and still stay connected to the network seamlessly.
• Flexibility: WLANs are highly versatile and can be deployed in various settings, including indoor and outdoor environments. This adaptability makes them suitable for different scenarios such as office buildings, public spaces, and outdoor events. For instance, a company using WLAN technology can easily extend its network to cover a new office floor without major infrastructure changes.
• Scalability: One of the key advantages of WLANs is their scalability. As network requirements evolve, additional Wireless Access Points (WAPs) can be incorporated with relative ease. This scalability ensures that more users can join the network or that network coverage can be expanded efficiently. For instance, a growing business can seamlessly increase its WLAN capacity to accommodate a larger workforce.
• Peripheral Access: Wireless devices connected to a WLAN have access to peripherals such as printers without the need for physical cabling. This accessibility enhances convenience and productivity in various settings, such as offices, where multiple users can wirelessly print documents from their laptops or mobile devices.

Disadvantages of WLAN

• Limited Coverage: WLANs have limited coverage compared to wired networks and can be further restricted by physical barriers such as walls and structures. This limitation can affect signal strength and connectivity in different areas within the network's range.
• Bandwidth Challenges: Bandwidth speeds in WLANs may face challenges, especially in high-traffic areas where multiple devices are accessing the network simultaneously. This congestion can lead to reduced performance and slower data transfer rates.
• Interference Concerns: WLANs are susceptible to interference from other electronic devices operating in the same frequency range. Interference can degrade the performance and reliability of the wireless connection, causing disruptions in connectivity.
• Security Vulnerabilities: WLANs are prone to security threats because wireless signals can be intercepted by unauthorized users. Without proper encryption and security measures, WLANs are vulnerable to attacks such as eavesdropping, unauthorized access, and data breaches. Implementing robust security protocols is essential to protect sensitive information and ensure network integrity.