3.1.4.2 Requesting Packet Pair Experiment

A higher-layer application or protocol requests a packet pair experiment through the initiator.

The initiator MUST instantiate a Packet Pair Session.

  • The Expected Message field MUST be set to 0x1E (Connection Handshake Success).

  • The Estimation Callback and Forced Estimation Callback fields MUST be set to the callback routines provided by the application or protocol, given as part of the Packet Pair Experiment request.

  • The contents of the Probe Array field MUST be provided by the application or protocol, also given as part of the Packet Pair Experiment request.

  • The Sequence Number field MUST be set to 1.

  • The Send Attempt field MUST be set to 0.

  • The Summaries Received field MUST be set to 0.

  • UDP Socket and TCP Socket are instantiated. If any of these objects fail to instantiate, then the initiator MUST fail the request and the associated session object is deleted.

  • The Interface Speed field MUST be set to the speed of the initiator's network interface used to connect to the sink device.

When a TCP connection is established to the sink, the initiator MUST send a Packet Pair Connection Handshake message using TCP Socket. The Per-Packet Pair Session Handshake Response timer MUST be enabled and set to expire after 250 milliseconds.

The initiator now waits for a message to arrive in order to continue processing the request. The request can only be completed when processing a message that has arrived.