Asked by: Dilip Lichtenstein
technology and computing computer networking

Are UDP packets fragmented?

Last Updated: 25th May, 2020

2 Answers. Any IP datagram can be fragmented ifitis larger than the MTU. With the IPv4 header being 20 bytes andtheUDP header being 8 bytes, the payload of a UDPpacketshould be no larger than 1500 - 20 - 8 = 1472 bytes toavoidfragmentation. This is assuming no IP options exist inthepacket.

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In this manner, what fragmented packets?

IP fragmentation is an Internet Protocol(IP)process that breaks packets into smaller pieces(fragments),so that the resulting pieces can pass through a linkwith a smallermaximum transmission unit (MTU) than the originalpacketsize. The fragments are reassembled by thereceivinghost.

Beside above, do switches fragment packets? IP fragmentation occurs when packetsarebroken up into smaller pieces (fragments) so they canpassthrough a link at a smaller maximum transmission unit (MTU)thanthe original (larger) packet size. The fragmentsarethen put back together by the host receiving them, ordestinationhost.

Similarly one may ask, what is UDP packet size?

The field size sets a theoretical limit of65,535bytes (8 byte header + 65,527 bytes of data) for aUDPdatagram. However the actual limit for the datalength,which is imposed by the underlying IPv4 protocol, is65,507 bytes(65,535 − 8 byte UDP header − 20byte IPheader).

Does MTU affect UDP?

5 Answers. UDP datagrams have little todowith the MTU size you can make them as big as youlike up tothe 64K is maximum mentioned above. When you create aUDPdatagram larger than the underlying MTU (which asindicatedis most often be ethernet) then it will be quietly bebroken upinto a number of 1500 byte frames.

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