In a hub, a frame is broadcast to every connected to it. It can not understand that the frame send to it is to be send to a only at one destination port. The hub has no way of distinguishing which frame should be sent to which port. Due to which it increase a lot of traffic on the network and may lead to increase the network response times.
Type of HUB
1 - Passive Hubs
They are just a mediator between devices in network. They don't have any option to assist us in troubleshooting faulty hardware or finding any issue in performance. They simply take all of the packets they receive and broadcast them across all ports.
2 - Active Hubs
They have all the features which passive hub have, including few additional features to monitor performance and, with few additional diagnostic capabilities. Active hubs are more expensive than simple, passive hubs and can be purchased in many configurations with various numbers and types of ports.
3 - Intelligent Hubs
They have capability of both Passive and Active Hubs. But they are intelligent than other. It has ability to offer flexible transmission rates to various devices. Intelligent hubs support standard transmission rates of 10, 16 and 100Mbps to devices using standard topologies such as Ethernet, Token Ring or FDDI.
Advantages and Disadvantages of Hubs
Advantages of Hubs
- They are used to bring multiple systems in one network.
- HUB is cheap as compared to other network devices.
- No processing is done at the hub to slow down performance.
Disadvantages of hubs
- They broadcast frames to all the ports. Which result in network slowdown.
- They are generally not intelligent to identify the network path, as a reason it broadcast to all devices connected to it.
They may lead to Collision of Data. - They cannot be used for Huge network.
- They run half duplex.
ENJOY! and stay connected.
0 comments :
Post a Comment