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Ethernet (Medium Access Control Protocol)
A single shared comm. Line Used by all (each check if “free” or “busy”) Message is broadcasted to all
Message has “destination address” and “message-body”
A B C D
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Ethernet Protocol (how it works)
Node A wants to send something to node D Message’s “destination address” = D Message is broadcasted to all…
Every Machine checks If not mine, then discard; else process message;
A B C D
My message!! Process it…
Not mine. Discard it…
D message
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Ethernet Protocol (Collision)
What if shared line is busy when node B wants to send? Eg: If node A is currently sending…. Node B waits… and send after node A is done.
What if many nodes are waiting… And simultaneously send when node A is done!
A B C D
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LAN
Length of collision delay is randomly generated.
So, different delays for different waiting nodes….
How to Resolve Collisions !!
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LAN (MACP – details from text)
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LAN (MACP – details from text)
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LAN (MACP)
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WAN Network….
Paths from B to F?
What if node C is faulty?
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WAN
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WAN
