Know Your Network: Switches, Bridges, and Routers

It isn't magic. Your data ends up where it needs to be thanks to some key components of your network infrastructure. Understanding their capabilities and the differences between each is a solid first step in planning your network.
(Page 1 of 2)

That panel of blinking lights staring you right in the face is key to your network infrastructure. Whether it's piled up on racks, or stacked together in a closet somewhere, bridges, routers and switches all play different roles in keeping your devices communicating with one another - not to mention keeping the Internet at large going.

In this article, we'll be taking a look at how each handles your information and what it does with it along the way.

In The Beginning

The old, trusty network hub was a handy device that saw many businesses expand upon their computer networks allowing for relatively simple deployment (at the time) of the expensive Ethernet technology. As beloved as they were, their design exhibited some performance issues when traffic passed over it.

This was due to the fact that it blindly broadcasts data over all physical ports, aside from the one that the data originated from. This invariably caused "collisions" when any other device attempted to transmit at the same time.

These collisions severely degraded the speed at which any connected computer could communicate since the hub needed time to resolve them as part of the CSMA/CD scheme that governed their operation. The time it took to retransmit frames meant slower speeds for the increasingly relied upon network segments and their ever-increasing workloads. The public broadcast of each packet also meant that any device connected to the hub could easily snoop on information being transmitted, a security nightmare to be sure.

Having no processing capabilities to speak of, the hub simply acts as a repeater, which is somewhat of a waste when you consider the wealth of information stored in a packet's header. The header has all manner of useful information that allows more robust networking gear to prioritize delivery and check data integrity, which a hub blindly ignores and passes along to any connected device.

Of course the onward march of technology meant the rather expensive switches of the day became more and more affordable as competition increased and embedded processors became cheaper and more abundant.

The Switch

The network switch is designed to efficiently handle any traffic it receives given its network-optimized, or often times, general purpose processors and its segmented connections between each physical port eliminating the device-wide collision issues found in hubs. The separate connections for each port isn't completely responsible for the improved performance as the on board processor is designed to read a data packet's header information and immediately route it to the correct physical port.

Netgear 24-port switchThat's not all a switch is limited to. Many high grade products have a fair measure of configurability and management features allowing one to set up Virtual LANs within their network, control link speeds for each individual port, and monitor data moving over the switch, something that normally wouldn't be easily possible given the separate links these devices maintain.

While Ethernet is a common connection, enterprise-grade routers and switches typically have modular interfaces that can accept new boards that sport support for established or newer high-speed interfaces such as Fibre Channel and ATM.


Page 1 of 2

 
1 2
Next Page





Comment and Contribute

 


(Maximum characters: 1200). You have characters left.