#TCP/IP

Question

What is the maximum size of data that the Network layer can forward to the Data link layer on the TCP layer, including header data?

1. Any size
2. 65,535 bytes
3. 65,515 bytes
4. 1500 bytes

This question has been asked before but given answers don’t explain reasoning properly.

Link to similar question : https://gateoverflow.in/152223/%23tcp-ip

If data link layer can have maximum 1500 Bytes data in a frame, then shouldn’t fragmentation happen at network layer ?  And therefore maximum data size that network layer can forward to data link layer should be 1500 Bytes.

Please explain how network layer can send 65,535 Bytes data when data link layer cannot have more than 1500 Bytes and fragmentation cannot happen at data link layer.

Comments

Source: https://networkengineering.stackexchange.com/questions/5587/how-layer-2-data-will-be-fragmented

So in conclusion if DLL can support packet of length 65535 B then Network layer can forward it to DLL.

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So, for TCP/IP which implies ethernet in DLL, we can say that NL can pass maximum 1500 Bytes to DLL ?

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@mark_twain Yes 

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@Aditya_ Explanation and answer given for this question is:

2. 65,535 byte

“The application layer can forward any size of data to the transport layer.

The transport layer divides the data into several segments and can forward a maximum of 65,515-byte data to the network layer. 

The network layer divides the data into packets that can pass a maximum of 65,535-byte data to the link layer. And in the data link layer maximum of 1500 byte of data can be forward. “

And i found same explanation on multiple sites. So, I guess given answer is wrong.