Re: [TICTOC] Enterprise profile update

[Richard Cochran <[e-mail]>]

On Wed, Apr 09, 2014 at 10:00:25AM +0000, John Fletcher wrote:
> Wojciech,
> 
> In your email below, you omitted the option b)
> 
> 9.5.11.1 states:
> 
> Delay_Req messages shall be transmitted as multicast except if:
> a) The optional unicast provisions of Clause 16 are used
> b) Specified otherwise by a profile
> 
> 
> In the case of the Enterprise and SMPTE Profiles, option b) is in effect, yes?

Well, in 1588, there is more to it than that.

19.2.2:

  A node that uses a transport protocol for which the mapping is
  defined in an annex of this standard shall conform to that annex.

D.3:

  PTP messages shall use the multicast message specified in Table D.1.

The enterprise profile uses the IPv4 transport, and it therefore nodes
must conform to Annex D, which in turn specifies using multicast. The
option of unicast is available via 16.1, and so the enterprise profile
should mandate that option.

At least, that is how I understand the text.

Another interpretation would be, "we can do anything we want regarding
unicast," justified by the vague wording of 7.3.1.

Thanks,
Richard