MTU usage for UDP packetsΒΆ

Check that UDP packets of full MTU size are sent and that jumbo frames are processed correctly.

Scenarios: X3-SYS04.

  1. Set MTU on IUT and Tester interfaces to mtu.

  2. Create a pair of connected UDP sockets on IUT and Tester.

  3. Assume that payload size in MTU-sized packet is mtu minus IP/UDP headers size.

  4. If tx is TRUE, sender is IUT and receiver is Tester, otherwise - the other way around.

  5. Create a CSAP on Tester to capture packets sent from (if tx is TRUE) or to (if tx is FALSE) IUT.

  6. In a loop for sends_num times:

    • Send some data from sender, choosing its size randomly but according to pkt_size.

    • Check that receiver socket becomes readable.

    • Receive and check data on the receiver.

    • Obtain packets captured by CSAP, check that sizes of all the packets except the last one correspond to mtu.

Dmitry Izbitsky Dmitry.Izbitsky@oktetlabs.ru

Parameters:

env

Testing environment:

mtu

MTU to be set:

  • 512

  • 1280

  • 1500

  • 1600

  • 9000

tx

If TRUE, send from IUT to Tester, else - the other way around.

pkt_size

Data size for send() call (in terms of MTUs):

  • less

  • equal

  • more

sends_num

How many times to send data:

  • 100