I'm developing PTP master using zynq hardware. I'm not understanding the significance of domainNumber field in the master. Because Delay response, Peer Delay response and Peer Delay Response Follow Up messages copy the domain numbers from the requests. and there is no clarity on messages received from master on other domain number like sync and follow up or announce we should respond or not. Please suggest a proper guide to refer.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I suggest you acquire a copy of the IEEE 1588 standard and copies of relevant PTP profile standards if you're developing a PTP master. This is the ultimate guide.
The domain number is of utmost significance - it is a key configuration parameter. A PTP node must ignore and drop any PTP messages from a domain different than its own. Exceptions are a) Peer to Peer TC operation where a node must reply to requests to any domain (a PTP P2P Transparent Clock has no awareness of what domains are being used), and b) any PTP profile that states that it allows simultaneous of multiple domains, such as the Enterprise Profile and possibly others in the future.
If ptpd copies the field, it does it only for convenience. Domain is verified first as soon as the message is received, and is dropped when it doesn't match our domain. That is the standard behaviour.
Last edit: Wojciech Owczarek 2016-06-30
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I'm developing PTP master using zynq hardware. I'm not understanding the significance of domainNumber field in the master. Because Delay response, Peer Delay response and Peer Delay Response Follow Up messages copy the domain numbers from the requests. and there is no clarity on messages received from master on other domain number like sync and follow up or announce we should respond or not. Please suggest a proper guide to refer.
The best guide is IEEE 1588 specification itself.
Only devices with same PTP domain number can communicate with each other. They should ignore messages from other domains.
This can be used to operate multiple PTP domains in one network, because they will ignore each other.
For basic installation, use default domain number 0.
I suggest you acquire a copy of the IEEE 1588 standard and copies of relevant PTP profile standards if you're developing a PTP master. This is the ultimate guide.
The domain number is of utmost significance - it is a key configuration parameter. A PTP node must ignore and drop any PTP messages from a domain different than its own. Exceptions are a) Peer to Peer TC operation where a node must reply to requests to any domain (a PTP P2P Transparent Clock has no awareness of what domains are being used), and b) any PTP profile that states that it allows simultaneous of multiple domains, such as the Enterprise Profile and possibly others in the future.
If ptpd copies the field, it does it only for convenience. Domain is verified first as soon as the message is received, and is dropped when it doesn't match our domain. That is the standard behaviour.
Last edit: Wojciech Owczarek 2016-06-30