IPv4 Fragmentation Interview Questions & Answers # 8 How fragmentation and Path MTU discovery works
A detailed video about how the IPv4 fragmentation works.
All possible interview questions related to fragmentation and path mtu discovery explained.
IPv4 fragmentation question asked almost all the network engineer interviews.
This video will be useful for those working in product support roles like TAC engineers
IPv4 packet fragmentation and packets reassembly using cisco packet tracer tool.
ipv4
Hi Siva, thanks for the nice explanation. I have one question related to the MF bit set, consider initially the first packet sent from R1 is 2000 and it gets fragmented into two packets at the next-hop R2 exit interface as 1500 and 500 (Two packets). Suppose there happens another fragmentation at R3 for the 1500 bytes packet, then it fragment it to 1000 and 500, as per the R3 device it is fragmenting the single 1500 to 1000 and 500. In that case, how does the fragmented packet 500 knows that there is another fragment packet of 500 is on the link? i.e. how does it set the MF bit to 1.
Siva.. what are the fields changes in IP header after fragmentation ?
In PMTU, only catch is DF bit, Each Route sets its own MTU in reply to source.
By far one of the best video on this topic
Sir thank for explaining.. one question when ip header is added which is 20 bytes then what about ethernet header ??
router doesn't reassemble the packet as far i know. Please check
In 1528 case ..1500 is data ,20 is ip header ,8 is ICMP header..i think simulator is not adding 8 bytes
if we initiate icmp from source to destination, based on the outgoing interface mtu fragmentation will happen.
so icmp reply from destinatiin to source also get fragmented based on the mtu size configured in the outgoing inteface ???
Hi Siva, Your content on the each topic and explanation is very good. Incase if you get a chance , Please upload , OSPF , BGP , Multicast and QoS related Interview questions & Answers videos as well.
Very Nice explanation !!!
Spr sir
Annae mass…really great explanation.
Please explain MSS vs MTU
I thought the 8 bit on top of the IP header of 20 is for the DF bit which is 8 bits.
Superb Video seen so far…!
I really liked the way you are explaning these small things we miss lot of time.
But i have question regarding the PMTU do we have any effects when we are enabling the PMTU ?
2nd question in cisco SDWAN world how does the PMTU works does it use the BFD packets ?
it would great if you can explain MSS and what relation is brings between the MTU.
Thank you
Best explanation of fragmentation seen so far