Bridge or gateway

jwills

Which do you use to connect two ntwks with different network access protocols? A bridge or a gateway? This book i'm reading actually says its a gateway and in another place its says its a bridge. Example: Connecting a Ethernet lan and a Token Ring lan.

royal

The answer is most definitely gateway.

A gateway "can" work on all layers of the OSI model. Because of this, there are many different functions of a gateway. A gateway can be used to translate different network architectures and protocols so the other network can understand what was transmitted by a foreign network. A gateway will translate and repackage data and transmit that data to the other network.

A bridge is basically a switch and works on the Datalink layer which means its job is to learn what what MAC addresses are associated to a given port. When a frame is being sent on the local network, the bridge can look at the destination MAC on that frame and see which port has that MAC assigned to it. It will then create a virtual circuit between the sending port and the receiving port and send the data directly between that virtual circuit. Because of this, it greatly reduces unneeded network chatter due to the data not being sent to every single port much like it would on a Layer 1 device, such as a hub. Having a bridge being able to send data directly to a port reduces the chance that collisions will occur. Because of this, each port is known to be in its own collision domain.

Does this help?