+1 vote
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Assume a datagram of length $5*10^3$ bytes needs to pass through five networks to reach its destination. The MTU’s of each network is 1000, 820, 850, 950 and 900 respectively. Then at destination how many datagrams has to reached and what is the offset value of 3rd fragment after fragmentation?

Fragments should be 11 and offset should be 200 right?

closed with the note: Ans--> 11 fragments  122 is the offset value

closed | 11 views
+1
Lol saw your other comment now. Finally we're on the same page :)

I always find it safer not to assume anything, especially in systems' based subjects. Just solve according to the data in the question.
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Yeah I realised my mistake

I forgot that 1packet is 800 followed by 176 and again 800 followed by 176....
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Good good. I like to draw a table with a column for each network, then trace each packet from start to the end. Helps keep track of ordering, fragment offsets, number of packets, etc. This is the kind of numerical where you can go miserably lost.
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I like to draw a table with a column for each network

This is good, let me solve next problems in this method.

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For this example, I roughly did the below:

 Link 1 Link 2 Link 3 .... 976+20 800 + 20 800 + 20 ... 176 + 20 176 + 20 .. 976+20 800 + 20 800 + 20 ...

Just track one or 2 packets diligently from left to right / source to destination. That way if you mess up, you can at least back track.