UDP Segment Format

For the UDP segment format in the length field

What does UDP header and UDP data mean?

Also what does the length of UDP header and UDP data actually mean?

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Met44

Bolton07 wrote: »

What does UDP header and UDP data mean?

If you're looking at a diagram with sections marked "UDP header" and "UDP data", they're just telling you the general format of a UDP segment. Inside the header are the header fields: source and destination port, total length, and a checksum. Inside the data section is all data passed down from layers 5-7 -- usually data from some user application.

Also what does the length of UDP header and UDP data actually mean?

The length field in the UDP header means the size, in bytes, of the header plus all data in the UDP data section. Suppose I sent a DNS request, and that the request (UDP data) was 43 bytes long. Since the UDP header itself has a length of 8 bytes, the value in the UDP header's length field would be 51.

Ryuksapple84

Met44 wrote: »

If you're looking at a diagram with sections marked "UDP header" and "UDP data", they're just telling you the general format of a UDP segment. Inside the header are the header fields: source and destination port, total length, and a checksum. Inside the data section is all data passed down from layers 5-7 -- usually data from some user application.

The length field in the UDP header means the size, in bytes, of the header plus all data in the UDP data section. Suppose I sent a DNS request, and that the request (UDP data) was 43 bytes long. Since the UDP header itself has a length of 8 bytes, the value in the UDP header's length field would be 51.

Nice Met44. That is a good explanation.

Take a look at this, this may help as well.

http://www.utdallas.edu/~cantrell/ee6345/pocketguide.pdf