Connecting Devices

*Three type bridgesTransparent bridges: means that stations are completely unaware of the presence of bridges. Used in Ethernet LANs. No burden in stations, bridges take care of all connection related functions.Source routing bridge: used in token-ring and FDDI LANs. Burden on stations. Source station needs to give route to the destination. Bridges just forward frames based on the route in the frame.

Mixed-media bridges: used to interconnect LANs of different types. These bridges have abilities of converting between LANs.

*Mixed-media bridgesSuch as connect Ethernet and token-ring networksConvert between two address representationsEthernet has maximum size of 1500 bytes but token-ring has no explicit limit. Drop frame if it is too long because bridges do not do segmentationToken-ring has three status bits A, C and E, but

no these bits in Ethernet, so no conversion for themDifferent transmission rate, so bridges need buffer to store extra frame temporarily.

Module II OVER!!!