Why So Many PTP profiles?

IEEE1588 (2008) is a huge standard, 269 pages long. It defines the Precision Time Profile (PTP), a protocol for distributing time over a packet network. Thing is, types of packet networks are ten a penny these days. There are industrial networks, power networks, telecom networks, audio networks, video networks, in-car networks just to name a few. All have subtly different requirements and therefore IEEE1588 contains loads of different options and features that simply aren’t appropriate for every network.

To cope with this, the good folks on the 1588 committee added profiles. A profile is “a set of required options, prohibited options, and the ranges and defaults of configurable attributes”. The idea was to allow other organisations (such as industry bodies or other standards bodies) to define which portions of the PTP protocol their industry would use. For example, ITU defined the G.8265.1 profile specifically for distributing accurate frequency (but not time) to mobile basestations.

Problem is, profiles have proliferated. ITU have defined 3 of them, IEEE themselves have at least 3, IETF tried to define one but never finished, IEC have one that is almost the same as one of the IEEE profiles but not quite, SMPTE have one, and there are probably others out there too.

It’s like they all claim to speak English, but they all have a different dialect – one speaks Geordie, one speaks American, another speaks Scots, and another speaks the Queen’s English. Each are sufficiently different for them to not quite understand each other.

So next time someone says “These are all PTP clocks, surely they’ll talk to each other?” you need to ask what profile they run before answering. Confusing or what?!

Tim Frost
Strategic Technology Manager, Calnex Solutions.

Recent Blogs

Related Blogs

banana skin

Will SD-WAN really be the savior?

Mar 13, 2019
The only way to prove it is to get validation on how it will perform against your needs…
1386 Read more
Four Boardroom Members

How to Optimise Your IT Network and Spend

Feb 06, 2019
Network emulation can be a key tool to overcome barriers in getting the most out of your…
2318 Read more

Responding to IT Network Issues

Jan 22, 2019
If simple remedial scripts are not enough to fix an IT network issue, a more…
3584 Read more

Archived Blogs

834 More

Timing not Telecoms

Nov 08, 2016
566 More

5G Coming Soon

Aug 22, 2016
571 More

What is 1588 PTP?

Aug 04, 2016
687 More

5G on the Horizon

Aug 01, 2016
564 More
607 More

What is a PTP Clock?

Apr 09, 2016
713 More

What is Time Error?

Oct 21, 2015
580 More

LTE-A & VoLTE Rollout

Sep 22, 2015
563 More

LTE Picks Up Speed

Aug 22, 2015
548 More

What is the Time?

Aug 22, 2015
556 More

Mobile and Sync

Aug 22, 2015
525 More

What is SyncE?

Aug 22, 2015
1017 More

Microwave Update

Aug 22, 2015
600 More

Unravelling Standards

Aug 22, 2015
581 More

Partial Progress?

Aug 22, 2015
554 More

Interpreting ITU

Aug 22, 2015
536 More

Confusion Rules!

Aug 22, 2015
560 More

Basestations Need Sync

Aug 22, 2015
573 More

ITSF 2015 Edinburgh

Aug 22, 2015
538 More

India to Follow China?

Aug 07, 2015
551 More
HOW CAN CALNEX HELP YOU FURTHER?

Click your area of interest below for more tutorials and real-world case studies.