PMP 450 - Frame Alignment Legacy Mode

Products PMP
1

Beginning with R14.1.1, we've added Frame Alignment Legacy Mode to the firmware, as a tool to help align timing when different software versions.  This information comes from the R14.1.1 Release Notes:

Frame Alignment Legacy Mode

In order to facilitate field hardware upgrades/replacements, "Frame Alignment Legacy Mode" has been added to newer software releases to allow for co-location with radios running older Canopy versions which cannot be upgraded at the same time, or to allow for slow rollout of upgrades on a per-sector basis, while maintaining compatibility with nearby sectors.

The best solution for resolving frame alignment issues for co-location is to maintain deployment of the latest software builds.

The web management interface contains a table (located at Configuration > Radio > Advanced) to reference which setting is appropriate for your network based on software versions and synchronization sources:

Figure 3 Frame Alignment Legacy Mode (non-900 MHz)

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Figure 4 Frame Alignment Legacy Mode (900 MHz)

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Please refer to the AP’s web management interface at Configuration > Radio > Advanced to determine the setting for the Frame Alignment Legacy Mode based on your network deployment. Note that this table differs between 900 MHz and 5 GHz hardware.

 

When utilizing Frame Alignment Legacy Mode, legacy radios must remain on a fixed synchronization source, or the Frame Alignment Legacy Mode parameter must be adjusted to accommodate the changes of the legacy radio synchronization source. New devices with Frame Alignment Legacy Mode set to ON (Mode 1 or Mode 2) will remain in synchronization with the legacy radio even if its own synchronization source is changed.

Table 12 Frame Alignment Legacy Mode attribute

Attribute

Meaning

Frame Alignment Legacy Mode

In order to align the frame start of co-located systems, the Frame Alignment Legacy Mode has to be selected from following options:

Frame Alignment Legacy Mode

Behavior (non-900 MHz radios)

Behavior (FSK 900 MHz radios)

OFF

By default frame start is aligned with devices with Timing Port synchronization

If the synchronization source changes (due to Autosync or otherwise) the radio will dynamically adjust its frame start to maintain alignment with the default frame start timing

By default frame start is aligned with FSK 900 MHz devices with Timing Port synchronization

If the synchronization source changes (due to Autosync or otherwise) the radio will dynamically adjust its frame start to maintain alignment with the default frame start timing

ON (Mode 1)

The radio will align with devices running software versions from 12.0 to 13.4.

The radio will align with FSK 900 MHz devices running software versions from 12.0 to 13.4.

ON (Mode 2)

N/A

The radio will align with FSK 900 MHz devices with software versions 11.2 or older.
2

If you're trying to troubleshoot compatibility of 450i AP to older software versions on 450 or 430 SMs (i.e. "legacy software"), then you might want to read this article.