Network Devices -Switch

A network switch is a computer networking device that links network segments or network devices. The term commonly refers to a multi-port network bridge that processes and routes data at the data link layer (layer 2) of the OSI model. Switches that additionally process data at the network layer (layer 3) and above are often called layer-3 switches or multilayer switches

Types of Switches

Modular switches: These types of switches offer more flexibility in their configuration. Modular switches typically come with different sized chassis that allow for the installation of different numbers of modular line cards the line cards actually contain the ports. The line card fits into the switch chassis like expansion cards fit into a PC. The larger the chassis, the more modules it can support.

Fixed configuration switches:- These types of switches are fixed in their configuration. What that means is that you cannot add features or options to the switch beyond those that originally came with the switch. The particular model you purchase determines the features and options available. For example, if you purchase a 24-port gigabit fixed switch, you cannot add additional ports when you need them. There are typically different configuration choices that vary in how many and what types of ports are included.

Stackable Switches
Stackable switches can be interconnected using a special back cable that provides high-bandwidth between the switches. Cisco introduced StackWise technology in one of its switch product lines. Stack Wise allows you to interconnect up to nine switches using fully redundant back plane connections.

As you can see in the figure, switches are stacked one atop of the other, and cables connect the switches in daisy chain fashion. The stacked switches effectively operate as a single larger switch. Stackable switches are desirable where fault tolerance and bandwidth availability are critical and a modular switch is too costly to implement. Using cross-connected connections, the network can recover quickly if a single switch fails. Stackable switches use a special port for interconnections and do not use line ports for inter-switch connections. The speeds are also typically faster than using line ports for connection switches.

Cisco Switches

Switches moves traffic base on MAC addresses. Each switch maintains a MAC address table in high-speed memory, called content addressable memory (CAM). The switch recreates this table every time it is activated, using both the source MAC addresses of incoming frames and the port number through which the frame entered the switch.

Switches perform their routing functions at the layers 2 model of the OSI. Some switches  process data at the Network Layer (layer 3), This types of switches are referred to as layer 3 switches or multilayer switches. Switches form an integral parts in networking LAN or WANs . Small office, Home office ( SOHO) applications normally, use a single or an all purpose switches .

Dell- PowerConnect Switches

 Managed 10Gb Ethernet Switch

10Gb entry-level Top-of-Rack switching, 1/10Gb Server/storage aggregation, and medium to large enterprise wiring closets in a compact, flexible and reliable switching platform


Managed Layer 3 Gigabit Ethernet
GbE entry-level Top-of-Rack switching, 1/10Gb Server aggregation, and enterprise wiring closets in a flexible, scalable switching platform.

Managed Gigabit Ethernet Switches
Server aggregation and access layer switching for enterprise campus through small office and branch offices with ease of management and simplified operation.