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13 bit fragmentation offset for last fragment

Wireshark Version used : 3.2.1 (v3.2.1-0-gbf38a67724d0)

I am capturing on wireshark on the link R1 to R2 to verify ip fragmenation . Please obsere the last Fragment 13 bit Offset value

<ping 192.168.30.3="" size="" 10000=""> .

My question is at before 7nth fragment . Attached wireshark capture .

Data size : 10000 - 20 = 9980 Number of Fragments : 9980/1480 = 6.7 = 7 fragments

1st Fragment : Offset = 0 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 1480

2nd Fragment : Offset = 1480, M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 2960

3rd Fragment : Offset = 2960, M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 4440

4rth Fragment : Offset = 4440 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 5920

5th Fragment : Offset = 5920 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 7400

6th Fragment : Offset = 7400 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 8880

7th Fragment : Offset = 8500 , M = 0 , Total Length = 1120 (i.e 1100 + 20 bytes) Total Data sent = 9980

Above is calculated logically . Now we will check the wireshark capture , go to ip header --> flags select this and observe the value this is on hex shown as 04 56 which is 1110 , but its shown as 688 .

13 bit fragmentation offset for last fragment

Wireshark Version used : 3.2.1 (v3.2.1-0-gbf38a67724d0)

I am capturing on wireshark on the link R1 to R2 to verify ip fragmenation . Please obsere the last Fragment 13 bit Offset value

<ping 192.168.30.3="" size="" 10000=""> .ping 192.168.30.3 size 10000

My question is at before 7nth fragment . Attached wireshark capture .

Data size : 10000 - 20 = 9980
Number of Fragments : 9980/1480 = 6.7 = 7 fragments

fragments 1st Fragment : Offset = 0 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 1480

1480 2nd Fragment : Offset = 1480, M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 2960

2960 3rd Fragment : Offset = 2960, M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 4440

4440 4rth Fragment : Offset = 4440 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 5920

5920 5th Fragment : Offset = 5920 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 7400

7400 6th Fragment : Offset = 7400 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes) Total Data sent = 8880

8880 7th Fragment : Offset = 8500 , M = 0 , Total Length = 1120 (i.e 1100 + 20 bytes) Total Data sent = 9980

9980

Above is calculated logically . Now we will check the wireshark capture , go to ip header --> flags select this and observe the value this is on hex shown as 04 56 which is 1110 , but its shown as 688 .

13 bit fragmentation offset for last fragment

Wireshark Version used : 3.2.1 (v3.2.1-0-gbf38a67724d0)

I am capturing on wireshark on the link R1 to R2 to verify ip fragmenation . Please obsere the last Fragment 13 bit Offset value

ping 192.168.30.3 size 10000

My question is at before 7nth fragment . Attached wireshark capture .

Data size : 10000 - 20 = 9980
Number of Fragments : 9980/1480 = 6.7 = 7 fragments

1st Fragment :
Offset = 0 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes)
Total Data sent = 1480

2nd Fragment :
Offset = 1480, M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes)
Total Data sent = 2960

3rd Fragment :
Offset = 2960, M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes)
Total Data sent = 4440

4rth Fragment :
Offset = 4440 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes)
Total Data sent = 5920

5th Fragment :
Offset = 5920 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes)
Total Data sent = 7400

6th Fragment :
Offset = 7400 , M = 1 , Total Length = 1500 (i.e 1480 + 20 bytes)
Total Data sent = 8880

7th Fragment :
Offset = 8500 , M = 0 , Total Length = 1120 (i.e 1100 + 20 bytes)
Total Data sent = 9980

Above is calculated logically . Now we will check the wireshark capture , go to ip header --> flags select this and observe the value this is on hex shown as 04 56 which is 1110 , but its shown as 688 .

Attached captured and few screenshots :

https://drive.google.com/drive/folders/1wKCZ0JgSHsWXm-_yGpvIQORmZvHW937i?usp=sharing

Regards, Sameer.