Network switches

A network switch is a device which connects network segments in a computer network. It is often called a switch hub. This term is often referred to a network bridge that processes and routes data at the second layer or data link layer of the OSI model. Layer 3 switches or multilayer switches are those that process data at Layer 3 and higher layers. This term network switch does not generally include passive network devices like hubs and repeaters. Kalpana introduced the first Ethernet switch in 1990.

What are the functions of a network switch?

The network switch, sometimes referred to as packet switch, works as a necessary part of most Ethernet LAN (local area networks). Network switches vary in number depending on the size of the network. As for example, a single switch is enough for a small office/home office network ( SOHO ). This is also true for an all-purpose converged device like gateway access to home broadband connection such as DSL (Digital Subscriber Line) or cable Wi-Fi router. The terminal device for the user has a router and peripherals that interconnects to the physical broadband technology like a Linksys 8-port or 48-port device, or in some cases, a telephone interfaced to VoIP technology.

A network switch functions at the data link layer or Layer 2 of the OSI model to make a distinct collision domain per port in a standartt 10/100 Ethernet switch. Say for example if you have 4 terminals or computers A, B, C, and D connected on four switch ports. Terminal A and B may send and receive data between them. This is likewise true for terminals C and D without interfering with one another. However, if they are using a hub, all terminals would be sharing bandwidth and would be running in half-duplex mode. In this case, there would be collisions and packets have to be retransmitted. Switch functions as a micro-segmentation which allows a terminal to have a dedicated bandwidth with point-to-point connection running in full duplex mode with no collisions.

Ethernet network switches ( Network switch port )

In wired home networks sharing a single internet connection, like dial-up connection, ethernet switches are sometimes used. This is done to achieve high-performance data transfer between computers such as when sharing large files or playing network games within the home network.

Network Hub/Switch

Is there any difference between a network hub and a network switch? Most of the time, the term “switch” is often misused. A network hub, or a repeater, is a network device that does not manage the traffic of data that flows through them. They are passive devices and merely repeat or broadcast packets that enters through them, thereby prone to collisions which causes slow down of the network because in a hub, the speed of individual port is shared. For example, a hub with a maximum speed of 10BT with five users would be 10/5 or 2BT. However, this is not the case in switches because the individual ports are not shared but connected independently at the maximum speed like 10BT or 100BT.

How to Select a Network Switch

Selection of a network switch is a key part of network design. Network switches vary with every company infrastructure and need. The Cisco network switch has various components. Included are among, but not limited to, Switching Modules, Power Supplies, Supervisor Engine, Switch Chassis, and IOS/CatOS software. In selecting and buying switches, one has to consider the design of the network infrastructure and its overall assessment or features. For example, for wireless designs, there are access points which a switch has to be interfaced with. Also, factors affecting the switch have to be considered like increased usage, assigning switch ports, lists of access control, trunking, spanning tree protocol, and increased power draw from Power over Ethernet (PoE).

Enumerated hereinbelow are the factors to consider in the selection of network switch:

1. Network assessment and design features for the desired network infrastructure;

2. Selection of the proper network switch with all the design features needed;

3. Network switches that has the proper scalability;

4. Cost and limit of the network infrastructure; and

5. The version of the IOS and/or CatOS software.

In the selection network switches, paramount consideration should be given to the network assessment and its design specifications for the proposed network infrastructure. Not only is the design accounted for, but also the configuration, equipment, and/or devices which will be used. The specification of the devices shall determine the performance, availability, and scalability of the network. The selection of the IOS and/or CatOS version of the software will vary according to the features of the network infrastructure. Budget or fiscal matters also play an important aspect in purchasing a cost-effective device suitable for the network design.