PTPv2 vs. gPTP

[ANG]

Hello there,

am new to Extreme Networks. I see in Switch Engine v33.11 User Guide that:

The Precision Time Protocol is currently available only for version 32.6 and later releases on ExtremeSwitching 5520 series switches, and version 33.1.1 on 7520-48Y and 7720-32C series switches. For this router, accurate synchronization of base stations to nanoseconds accuracy is critical to minimize service disruptions and eliminate dropped connections as calls move between adjacent cells.

Do you know why the X platforms (i.e. non-universal HW) does not support it? It seems only gPTP is supported with Xabc hardware...Can anyone elaborate?

Thanks in advance.

[James_A]

It used to be supported on X670-G2 and X460-G2 but was removed in 30.6 and 31.1 https://extreme-networks.my.site.com/ExtrArticleDetail?an=000079685

Also note that Switch Engine and EXOS are different now

[ANG]

Hello James_A,

>Also note that Switch Engine and EXOS are different now

I know of ExtremeXOS® v33.1.1 Licensing Guide only. Can you elaborate and provide some reference? What OS can be used on Xabc models? And the same OS can be used on the universal platforms?
Thanks, ANG.

[James_A]

https://documentation.extremenetworks.com/Switch%20Engine%20v33.1.1%20Licensing%20Guide/GUID-3F8A7FE...

AVB Feature License. Feature: Generalized Precision Time Protocol (GPTP) (and others). Platform support: All platforms, except 4120, 4220, 5320-XT, 7520, and 7720.

All Universal Hardware platforms have the AVB Feature License included in the Base License. You do not need to separately purchase and install the AVB Feature License for supported Universal platforms.

X### models are ExtremeXOS, universal switches - 5[3457]20/7[57]20 can run switch engine (which is based on EXOS) or fabric engine (based on VOSS).

[Gabriel_G · Accepted solution]

Hi ANG,

Let's clarify the different ways people us PTP/gPTP:

1) PTP Multicast Transport Between Endpoints
-> Basic deployments where PTP is passed between endpoints via multicast is supported on all EXOS platforms.
-> In this case, PTP is treated like any other multicast traffic and the switch does not participate in PTP clocking operations
-> Specific configuration is generally not needed here, IGMP and IGMP snooping are enabled by default for all VLANs to facilitate multicast transport.

Related:
https://extreme-networks.my.site.com/ExtrArticleDetail?an=000079341&q=dante

2) PTP Clock Operation by Switches
-> If you want the switch to participate in PTP clocking operations, you'll need to be on specific platforms that have the relevant hardware to support PTP operation. This is a less common setup, hence not supported on many switches.
-> The switch can behave as a transparent clock, boundary clock, etc.

Related:
https://extreme-networks.my.site.com/ExtrArticleDetail?an=000081476&q=ptp%20configuration

3) gPTP Clock Operation by Switches
-> gPTP is often used in Audio/Video networks for AVB operation. 
-> This is supported on most platforms that support the AVB feature pack ('enable AVB ports ...')
-> In this deployment, the switch does participate in gPTP time sync between endpoints

Most people using PTP are in bucket #1 where PTP is just passed between endpoints.
If you actually need the switch to participate in PTP clocking operations, you'll need specific hardware (sometimes a license as well).
Otherwise, gPTP is supported on most platforms for AVB (AVB License on non-universal, Base license on most Universal)

Hope that helps!