Unexpected PDelay_Request Message

Enhanced PTP User Guide (UG1602)

Document ID
UG1602
Release Date
2022-10-18
Revision
1.0 English
Figure 1. Flowchart for Unexpected PDelay_Request Message

The peer-to-peer delay method is an alternative to the more widely used end-to-end delay method. sfptpd will support both methods with the default being end-to-end. The delay method is configurable in the sfptpd configuration file.

  • The end-to-end delay mechanism:
    Delay_Request, Delay_Response
  • The peer-to-peer delay mechanism:
    PDelay_Request, PDelay_Response

When sfptpd is using the end-to-end delay method, it will generate the “Unexpected...” warning if a PDelay_Request message is received.

When sfptpd is using the peer-to-peer delay method, it will generate the “Unexpected...” warning if a Delay_Request message is received.

When peer-to-peer working is used in the network, every PTP node must support and use it.

Mixing end-to-end with peer-to-peer methods is not supported in any PTP domain. All PTP nodes within a PTP domain must use the same method.

When peer-to-peer delay is used every node in the PTP network sends both the PDelay_Request and PDelay_Response messages to the neighboring PTP node.