LAN switching is a form of packet switching in which the data packets are transferred from one computer to another over a network. Switching technologies are vital to network design, as these technologies permit the traffic to be sent only where it is required; in most of the cases, making use of fast, hardware-based methods.
LAN switching technology helps to improve the overall efficiency of local area networks and address the existing bandwidth issues.
LANs (local area networks) are easy to establish, but complex to maintain. For LANs, different networking techniques are used to implement and maintain. LAN switching includes mainly 4 types of switching. They are as follows:
1. Layer 2 Switching:Layer 2 switching is hardware-based switching. It makes use of the (media access control (MAC) addresses on the network interface cards (NICs) of the host to determine the location to forward the frames. Advantages of layer 2 switching are its high data transmission speed with low latency and cost.
2. Layer 3 switching: Layer 3 switching provides similar functionality as router. Some fundamental functions are as follows:
Uses TL (time to live)
Identify paths on the basis of logical addressing
Enables hardware-based packet forwarding
Offers highly efficient packet switching
High speed data transmission with low latency
3. Layer 4 switching: An enhanced version of layer 3 switching, layer 4 switching uses hardware-based switching with the addition of applications like Telnet and FTP. Layer 4 switching uses routing on the basis of port numbers. Access list filtering completely functions on layer 4 switching. The most significant advantage of layer 4 switching is that the network admin is able to configure a layer 4 switch for prioritizing data traffic by application, which implies that a quality of service (QoS) may be defined for every user.
4. Multi-Layer Switching: Multi-layer switching (MLS) provides low latency and high performance. All three layer switching (2, 3 and 4) are combined in MLS. MLS makes use of the following while making switching decisions:
Source and destination address (MAC and IP)
Protocols details (fields)
Source port number and destination port number