Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-13 Thread Miroslav Lichvar
On Thu, Feb 09, 2023 at 11:37:52AM -0800, Richard Cochran wrote: > On Thu, Feb 09, 2023 at 01:32:14PM +0100, Miroslav Lichvar wrote: > > > Yes, but if you know the length of the chain and charateristics of all > > clocks and their timestamping, you can tune the servos to minimize > > their gain

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-09 Thread Richard Cochran
On Thu, Feb 09, 2023 at 01:32:14PM +0100, Miroslav Lichvar wrote: > Yes, but if you know the length of the chain and charateristics of all > clocks and their timestamping, you can tune the servos to minimize > their gain peaking for the synchronization of the last clock. This can > be done with

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-09 Thread Miroslav Lichvar
On Wed, Feb 08, 2023 at 07:18:17AM -0800, Richard Cochran wrote: > > BTW, synchronization with BCs can work better than TCs if the PLLs are > > well implemented and tuned. TCs are the simpler and safer approach. > > There was a simulation study showing "gain peaking" from a long chain > of

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-08 Thread Richard Cochran
On Wed, Feb 08, 2023 at 08:28:54PM +, Nemo Crypto wrote: > What does NIH mean? Not Invented Here? yes. ___ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-08 Thread Nemo Crypto
What does NIH mean? Not Invented Here? On Wednesday, 8 February, 2023 at 10:18:21 am GMT-5, Richard Cochran wrote: On Wed, Feb 08, 2023 at 09:33:49AM +0100, Miroslav Lichvar wrote: > On Tue, Feb 07, 2023 at 07:39:48PM -0800, Richard Cochran wrote: > > Sure, if you have a chain

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-08 Thread Nemo Crypto
Hi Richard, Thanks for your valuable inputs. 802.1AS is chosen not for better performance in this particular case, but because we should be using Automovitve Profile and compliant to AVnu gPTP standard.But I agree with you, I am waiting for the prototype HW to see how ptp4l BC functions with

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-08 Thread Richard Cochran
On Wed, Feb 08, 2023 at 09:33:49AM +0100, Miroslav Lichvar wrote: > On Tue, Feb 07, 2023 at 07:39:48PM -0800, Richard Cochran wrote: > > Sure, if you have a chain topology of 15 hops, then you would start to > > see benefits from using TAB over BC. But who has that kind of network? > > > > Even

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-08 Thread Miroslav Lichvar
On Tue, Feb 07, 2023 at 07:39:48PM -0800, Richard Cochran wrote: > Sure, if you have a chain topology of 15 hops, then you would start to > see benefits from using TAB over BC. But who has that kind of network? > > Even then, would an 802.1as TAB outperform an ieee 1588 TC? The draft I saw

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-07 Thread Richard Cochran
On Tue, Feb 07, 2023 at 03:59:23PM +, Nemo Crypto wrote: > >As a practical matter, I don't see why you can't simply use linuxptp's > >BC mode, configuring the two ports with 802.1as settings. > > >Who could tell the difference? > Would the linuxptp's BC send all the TLVs required for

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-07 Thread Nemo Crypto
>As a practical matter, I don't see why you can't simply use linuxptp's >BC mode, configuring the two ports with 802.1as settings. >Who could tell the difference? Would the linuxptp's BC send all the TLVs required for 802.1AS? I mean, the Time Follower that receives Sync/Followup from

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-07 Thread Richard Cochran
On Tue, Feb 07, 2023 at 01:49:42PM +, Nemo Crypto wrote: > Then the actual question becomes, whether linuxptp has support for > IEEE802.1AS Time Aware Bridge (Time Relay)? No, TAB/Time Relay is not supported. There was some initial work done (check the archives), but that was never

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-07 Thread Nemo Crypto
Thanks Miroslav! Then the actual question becomes, whether linuxptp has support for IEEE802.1AS Time Aware Bridge (Time Relay)? Can any other expert comment please? On Tuesday, 7 February, 2023 at 03:29:48 am GMT-5, Miroslav Lichvar wrote: On Mon, Feb 06, 2023 at 04:17:30PM +,

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-07 Thread Miroslav Lichvar
On Mon, Feb 06, 2023 at 04:17:30PM +, Nemo Crypto wrote: > Hi Miroslav, > Thanks! > In my understanding of "Time Aware Bridge", it doesn't correct/adjust/tune > the PHC. Is that not correct? Looking at some freely available drafts of 801.AS, yes, it seems the clocks are supposed to be

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-06 Thread Nemo Crypto
Hi Miroslav, Thanks! In my understanding of "Time Aware Bridge", it doesn't correct/adjust/tune the PHC. Is that not correct? Nemo On Monday, 6 February, 2023 at 11:01:51 am GMT-5, Miroslav Lichvar wrote: On Mon, Feb 06, 2023 at 03:21:25PM +, Nemo Crypto wrote: > Hi

Re: [Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-06 Thread Miroslav Lichvar
On Mon, Feb 06, 2023 at 03:21:25PM +, Nemo Crypto wrote: > Hi Linuxptp-users, > I am using gPTP 802.1AS profile for my network. My simplified network > topology looks like this, > TimeLeader --> Eth Switch (802.1as Time Aware Bridge)-->Processor > (BC?)--->TimeFollower > In the above

[Linuxptp-users] IEEE802.1AS gPTP Boundary Clock

2023-02-06 Thread Nemo Crypto
Hi Linuxptp-users, I am using gPTP 802.1AS profile for my network. My simplified network topology looks like this, TimeLeader --> Eth Switch (802.1as Time Aware Bridge)-->Processor (BC?)--->TimeFollower In the above topology, The processor runs linuxptp (ptp4l & phc2sys) has 2 interfaces. One