TestBook

Question

A packet has arrived in which the offset value of 2nd frame is 450, the header length is 20 and the value of the total length field is 1000. What is the number of the first byte in the first frame and the last byte in the last frame if the size of IP packet of size 3500 bytes?

Answer 1

Header length = $20*4=80$ (Scaling factor is $4$ for header length)

Total length $=1000$

Data length = $1000-80=920$

Offset of $2^{nd}$ frame = $450*8=3600$ (Scaling factor for offset is $8$)

Last byte of First frame = $3599$

First byte of first frame = $3599-920+1=2680$

Last byte of last frame = $2680+3500-1=6179$

Correct me if i'm wrong.