I am going through a course of networking and want to know the difference between the mentioned devices. I have heard that the switches:
Establish a temporary connection between the devices connected to it and wanting to communicate.
If this is the case then why does the connection needs to be temporary or where is it helpful?
Reads the destination address from packet header and sends it to the mentioned receiver.
Establish permanent connection amongst networks.
If temporary connection is sufficient, why have a permanent one?
Forwards packets only if it were requested by any of the host in the rest of the network. (For which a filter table is maintained)
Are the following true or false. Correct them if false:
I can only use either a router or a bridge to connect same protocol following multiple networks (amongst themselves).
All the devices are gateways falling under different layers of OSI model and have ability to translate between all the protocols of that layer.(for eg. router is a gateway falling in network layer and is capable of translating protocols TCP followed by network A to UDP followed by network B (two of the protocols operating at networking layer) and vice versa)
A gateway in general operates in application, session and presentation layer.
Also I am not convinced by the fact that a protocol needs to be translated into another and hence the need of devices. The reason is that if the networking by definition means that it needs to agree on a protocol, why is there a need of translation? I would be grateful to the answers clearing the doubts(without raising any other :-)).