If you are able to take a look into the IEEE 1588 standards, see section 9.5.11 (Transmission of a Delay_req message) and in particular section 9.5.11.2 (Timing requirements). It states that:
The transmission of the Delay request message from a port SHALL be limited as follows: - The initial may be transmitted when required - Following messages in a way such that the mean interval, in seconds, is not less than the value of 2^logMinDelayreqInterval seconds (where logMinDelayreqInterval us the logMessageInterval field of the last Delay response received) The standard provides also two option to meet this requirement. HTH William -----Original Message----- From: Miroslav Lichvar [mailto:[email protected]] Sent: 17 March 2015 14:03 To: Chandra Mallela Cc: Ledda William EXT; [email protected] Subject: Re: [Linuxptp-users] Port option: logMinDelayReqInterval On Tue, Mar 17, 2015 at 12:47:13PM +0000, Chandra Mallela wrote: > 1. Which field in the delay response indicates the value to the slave > announed by the master? Is it logMessageInterval? Yes. > 2. DelayReq packet is sent by the slave. Thus, the number of DelayReq > packets to be sent is to be controlled by the slave. Am I right? Why should > it be an option with master? Master tells slaves how often they should be polling the master. > An answer to my own question: It is the master being burdened to respond to > possibly many number of slaves. Hence, it controls the number. Is this the > rationale for what you have mentioned below? Yes, I think that's correct. The sync interval is controlled by master, so the delay interval should be too. -- Miroslav Lichvar ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Linuxptp-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linuxptp-users
