Cambium is officially releasing the PMP450x Radio 21.1 software.
Radio software and documentation can be found at https://support.cambiumnetworks.com/files/pmp450/, and will be available on cnMaestro cloud within 24 hours.
System Release 21.1 is primarily a bug fix release. It also includes some CBRS features, support for the new PMP 450m 3 GHz P7 hardware and support for PMP 450m 5 GHz P9 hardware.
First upgrade Subscriber Modules (SMs) to System Release 20.0 or later version and then upgrade the AP. Otherwise, SMs will connect but at a maximum modulation rate of 2X MIMO- B until both sides are running on System Release 20.0 or later version.
Features introduced in System Release 21.1
System Release 21.1 supports the following new features:
- Channel Change if only SMs are impacted
- Restriction of CBRS channel hunts to the same bandwidth, for PMP 450m operators who prefer to avoids an AP reboot
- Handling of CBRS SAS channel enforcement
Channel Change if only SMs are impacted
The System Release 21.1 introduces a new feature that allows the AP to automatically find and move to a new channel or lower the bandwidth, when a significant number of SMs have been affected by termination or suspension, even though the AP itself has not been impacted.
Three new configuration parameters are added to the Configuration → CBRS → Configuration page as shown in this screenshot:
Change Channel if only SMs are impacted: When enabled, this feature allows the AP to automatically find and move to a new channel or decrease the bandwidth, when more than the SM Percentage Threshold for Channel Change percentage of SMs has been impacted by termination or suspension, even though the AP itself has not been impacted.
Note that the Alternate Channel Selection feature must also be enabled for the AP to hunt for a new channel due to the Change Channel if SMs are Impacted feature. If an operator elects to run with Alternate Channel Selection enabled but Change Channel if SMs are impacted feature is disabled, the AP still performs automatic channel selection, but only in cases where the AP is directly impacted by terminations or suspensions.
If the Alternate Channel Selection feature is disabled, but the Change Channel if Only SMs are Impacted feature is enabled, if enough SMs are impacted by terminations or suspensions, the AP will still reduce the Bandwidth if authorized grants are available, but it will not hunt for a new channel.
Original Channel Restore Time: When this feature is triggered via SM suspensions, the AP continues to heartbeat the original channels for itself and all the SMs, while operating on the temporary channels or reduced bandwidth for at least this length of a period after moving to these temporary channels or reducing bandwidth. When this timer expires, the AP can move back to the original channels and/or bandwidth if enough suspended SMs have become authorized on the original channels.
On the bottom of the HOME → Session Status page of the AP, a new counter associated with this feature has been introduced. It is a computation of the number of SMs that need to experience a termination or suspension before this feature is invoked. For example, if Threshold for Channel Change is left at its default value of 10%, the 4 shown in the screenshot below indicates that this is a sector with 40 SMs.
System Release 21.1 does not support this feature for PTP BHM/BHS setups. Such support is expected to be added later in 2022.
Restriction of CBRS channel hunts to the same bandwidth, for PMP 450m operators who prefer to avoid an AP reboot
The PMP 450m APs require a reboot when the channel bandwidth is changed. For PMP 450m, operators who use the CBRS Alternate Channel Selection feature, but prefer to avoid the outage caused when the bandwidth is automatically adjusted, they can now leave the Alternate Channel Selection feature enabled, while disabling the Reboot for Channel Bandwidth Change feature. When a channel hunt is automatically invoked due to terminations or suspensions, the AP will only hunt for channels with the same total bandwidth currently in use.
Handling of CBRS SAS channel enforcement
Both Google and Federated Wireless have plans to implement a feature that can enforce a pre-determined frequency plan. They will do the calculations at CPAS using the new frequencies, and right after CPAS, they will terminate the old frequencies. When such a SAS-initiated channel termination is sent to an AP/BHM, pre-System Release 21.1 software handles this without any issue if the channel the SAS is intending to move the sector to does not overlap in frequency with the current operating channel. If, however, the new target channel overlaps with the existing operating channel, pre-System Release 21.1 software shrinks the bandwidth rather than moving the sector to the entire new channel made available by the SAS. This System Release 21.1 AP/BHM CBRS feature is introduced to handle the SAS channel enforcement more optimally, by triggering a channel hunt even if the AP/BHM still has unterminated grants.
SAS support is expected likely sometime late in the 2nd quarter of 2022, although exact dates are not yet finalized.
Additional enhancements in System Release 21.1
| Products Affected | Tracking | Description |
|---|---|---|
| All | CPY-17968 | Do not show the Reboot button after the reboot has been initiated. |
| All | CPY-17963 | Automatically Reboot upon out of memory failure. |
| AP | CPY-17928 | New OID for connected SMs Color Code Priority. |
| 450m | CPY-17872 | Support for new Ethernet PHY device on 450m. The newer PHY chip 450m devices can be recognized by checking the Statistics → Ethernet entry for PHY ID on the AP GUI. The older devices shows Atheros 8033 while the new 450m devices shows Qualcomm 8081. These newer devices require a minimum software revision of System Release 21.1. |
| 450m | CPY-17870 | Slight packet per second and throughput improvement. |
| All | CPY-17855 | Automatically reboot Radio with Bandwidth Phase Lock Loop (PLL) Lock lost to attempt recovery. |
| CBRS | CPY-17231 | Follow-Me does not work with multi grant. |
| CBRS | CPY-16631 | Move CBRS heartbeat timing to relative time instead of absolute time. |
Problems and limitations corrected in System Release 21.1
| Products Affected | Tracking | Description |
|---|---|---|
| CBRS | CPY-18004 | CBRS AP, running System Release 21.0, reset due to SAS empty responseData. |
| SM | CPY-17996 | The Reboot Required message was not displayed when a certificate was uploaded successfully. |
| CBRS | CPY-17983 | In termination case, no longer restricting Bandwidth in channel hunting algorithm as a function of the number of available channels. Note: This is needed to support the SAS channel enforcement feature. |
| 450m | CPY-17971 | Watchdog Reset due to buffer gather error. |
| AP | CPY-17951 | Rename the AP MIB OIDs, that had the same name in SM MIB: spatialFrequency, adaptRate, platformVer. |
| CBRS | CPY-17940 | AP does not send Spectrum Inquiry request and grant request for target frequency when relinquished AP is operating in the temporary channel. |
| 450m | CPY-17896 | Uplink sounding reassessments more frequent with over 128 slots in the uplink. |
| CBRS | CPY-17947 | Do not relinquish the original channel in SM while operating on a temporary channel. |
| All | CPY-17922 | In some instances, SM sends PPPoE PADI as a unicast packet instead of sending it as a broadcast packet. |
| CBRS | CPY-17920 | calloc1 failed: out of heap and Internal error due to memory leak with CBRS when changing the configuration or exporting configuration. |
| All | CPY-17908 | Removed SM and PTP EIRP limits in 900 MHz bands for Brazil. |
| 450m | CPY-17897 | 40 MHz 5 ms Downlink Data percentage 33% or lower results in 1X modulation. |
| All | CPY-17892 | Updated Vietnam regulatory requirements for PMP products. |
| SM | CPY-17887 | NAT DNS Server Relay stopped working. |
| SM | CPY-17881 | Maximum Receive Power was incorrect on UI. |
| All | CPY-17869 | After every 17 days of uptime on System Release 21.0, uptime reads 1 year and SYSUPTIME OID was not correct. |
| PTP BHM | CPY-17862 | Receive Target Level configuration parameter was missing in the configuration file. |
| 450m | CPY-17854 | Added more detail logging for 450m Watchdog resets due to canopy abort. |
| 450m | CPY-17842 | Occasional invalid Ethernet TX frame, CRC mismatch. |
| PMP 450 | CPY-17823 | Follow-Me feature was not following hardware frequency limits. |
| CBRS | CPY-17819 | Channel hunt algorithm should consider SI response sorted, if any 5 MHz slices were present. |
| All | CPY-17817 | IPv6 configurations were missing from the configuration file. |
| AP | CPY-17792 | AP LAN2 Private Radio Network Interface must end in .1. |
| All | CPY-17586 | FatalError reset due to Invalid NiBuff error when processing DHCP Relay packet with no DHCP End Option (Code 255). |
| All | CPY-17341 | Memory leak when exporting user certificates when exporting the configuration file that can lead to calloc1 failed and Internal Error. |
| CBRS | CPY-17172 | Device Agent socket connection goes down on CBRS sync from cnMaestro. |
| 450m | CPY-17060 | 450m crashed due to GPS buffer overrun with bad serial input. |
| All | CPY-17016 | No HTTP access and/or occasional reset with security scans. |
| All | CPY-16965 | SM NAT mode with VPN on its LAN stops passing traffic when NAT table entries are greater than 1500. |
| 450m | CPY-16487 | Downlink beamformed powers require a reboot to update correctly. |