Both Wireless LAN (WLAN) and Wired LAN (Local Area Network) aim to facilitate network communication and data sharing, but their implementation and protocols at certain OSI layers differ, especially at the lower layers. Below is a detailed comparison:
- Physical Layer
- Wired LAN: Uses physical media such as Ethernet cables (copper) to transmit data, involving electrical signals and physical cable characteristics.
- Wireless LAN: Employs radio frequencies or infrared signals as the transmission medium, transmitting data via electromagnetic waves through the air.
- Data Link Layer
- Wired LAN: Typically uses Ethernet technology which handles framing, error checking and includes MAC (Media Access Control) addressing.
- Wireless LAN: Uses Wi-Fi (IEEE 802.11) protocols that also manage framing and error checking but must additionally address signal attenuation and interference.
- Network Layer
- Both Wired and Wireless LAN: Generally employ the same protocols like IP (Internet Protocol), handling logical addressing and routing to determine the best paths for data packet transmission.
- Transport Layer
- Both Wired and Wireless LAN: Use protocols like TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) which are focused on providing reliable data transfer and are agnostic to the network type.
- Session Layer
- Both Wired and Wireless LAN: Manage connection controls between computers, handling session setup, maintenance, and termination, with minimal difference between network types.
- Presentation Layer
- Both Wired and Wireless LAN: This layer translates data between the network and application layers, handling encryption, compression, and conversion, operating independently of the network’s physical type.
- Application Layer
- Both Wired and Wireless LAN: Provide interfaces and services for software applications, including protocols like HTTP, FTP, SMTP, with functionality consistent across network types.
Key Differences:
- Speed and Bandwidth: Wired LAN typically offers faster speeds and more stable bandwidth compared to WLAN, which may be affected by physical barriers, distance from the router, and interference from other devices.
- Security: Wired LANs are often more secure, requiring physical access to network cables, whereas WLANs are susceptible to security breaches if not properly secured.
- Cost and Scalability: Installing and expanding wired networks can be costly and inflexible. In contrast, WLANs provide easier scalability and lower initial costs.
While both types of LAN operate similarly at the higher OSI layers, their significant differences are mainly found in the physical and data link layers, where their data transmission methods greatly diverge.