A wired or a wireless network allows computers to communicate and share information with each other. Various technology components are required to enable this connectivity and to efficiently manage the data traffic that flows over such networks. Network hubs and network routers are two such components. Both have important but very different roles to play in enabling network connectivity.
Network hubs are relatively simple hardware devices that can be used to tie multiple computers together into a single network of interconnected systems. Hubs are typically used by consumers to build home networks and by small businesses looking to deploy local area network (LAN) functionality. The devices themselves are typically small rectangular boxes with several ports in the front that allow computers and other network devices to be connected into them. Small hubs come with between four and five ports while enterprise class devices can support more than two dozen ports.
In terms of functionality, a network hub basically allows all devices that are connected to it to communicate and share information with each other directly. All data packets that flow into a hub through one port are redirected to all the ports on the device including the one from which the traffic originated. All computers that are connected to the hub see and share all the data traffic that flows through the hub.
A hub is typically not designed to inspect or read any of the traffic packets that pass through it. So unlike more sophisticated network devices, a hub is not aware of the source of the traffic passing through it or of the intended destination. Most hubs typically support data transfer rates of either 10 megabits per second or 100mpbs, while some support both speeds. Many hubs that are currently in use are based on what’s known as the Ethernet standard for LAN connectivity. Computers are connected to such hubs via standard RJ-45 twisted-pair connectors. More recently, vendors have also started shipping hubs that support USB connectivity.
Network routers meanwhile are considerably more sophisticated pieces of technology and play a far more fundamental role in directing traffic over networks and the Internet than hubs. While hubs are used to connect multiple computers together into a single network, a router is used to link multiple wired or wireless networks together. In the home networking context, a network router is the device that connects the home computer or home network to the external Internet.
In the context of a large enterprise network, a router is used to intelligently direct traffic to the destinations they are intended for. Unlike hubs, routers are designed specifically to inspect data traffic, determine the source of the traffic and make intelligent decisions on how to route it to the ultimate destination based on considerations such as network bandwidth and network availability.
Routers use what are known as routing tables to determine the optimal path for sending traffic through from source to destination. Routing tables contain information on the network connections that need to be used to send a particular data packet from source to destination. In some cases such routing tables can be ‘dynamic’, meaning the traffic paths specified in them could change depending on network availability. Other routers use static routing tables for receiving and forwarding traffic. In such cases, network administrators manually enter the traffic path in the routing table which the router then uses always to direct traffic passing through it.
Unlike hubs which allow for no customization, network routers can be configured to filter traffic based on the source or the destination of the traffic. This ensures that important traffic is always given a higher priority on the enterprise network compared to non-essential traffic. Corporate networks often have numerous routers on their networks, each one installed at a network connection point for seamlessly receiving traffic from one segment and forwarding it to the next. Large broadband routers play a similar and vital function in directing traffic over the broader Internet.
Most routers come in the form of hardware appliances with numerous ports in them for connecting computers and networks together. But routing software is also available that allows an ordinary PC to perform all the functions of a specialized routing appliance.