Gateforum Correspondence Course ( Page# 38, Q# 2)

Question

What layer of the OSI model is designed to perform error recovery functions?

• A. physical
• B. data link
• C. network
• D. transport

Comments

B.DLL

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B and D

Answer 1

DLL is responsible for bit level frame error detection / correction / retransmission.

Transport layer is responsible for end-to-end delivery guaranty. 

Transport layer error control is a redundant necessary.

Comments

@Debashish. I think end-to-end delivery guarantee for transport layer is only applicable for TCP protocol. But there may be other protocols as well like UDP which dont perform error recovery.

So, I think DLL is only the option.