topic Re: AIR-AP2802I-E-K9 APs PoE diffrences in Wireless

AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Mon, 23 May 2022 09:51:29 GMT

Hi!

We are running a 5520 WLC and we have got many different AP models running.

We have many AIR-AP2802I-E-K9 APs that are running in different ways, meaning some are running by PoE switch and some are running with a Power injectors.

Some PoE switches we have can only PoE and not PoE+, example is SG-300 switches.

When i check the power consumption that the AIR-AP2802I-E-K9 APs are using on the SG-300 switches i see that the AIR-AP2802I-E-K9 are only using 9.5 watts.

When these APs are using a power injectors then they use about 25 watts!

What is the practical difference between 9.5 and 25 watts?

I did some Googling and find that the antennas number on an AP maybe affected with low wattage! is that right?

How and where to see the difference?

AIR-AP2802I-E-K9 model is 4x4 do they work like 1x1 with low wattage? where can i show this ?

We have thousands of laptops that are 2x2 so 1x1 is bad i think !

Same is right with APs like 1850 model!

Another question is about Clientlink 4.0!

When i check AIR-AP2802I-E-K9 i see that legacy beamforming is disabled, how to show that Clientlink 4.0 is enabled on AIR-AP2802I-E-K9 model?

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Mark Elsen — Mon, 23 May 2022 10:31:07 GMT

>....What is the practical difference between 9.5 and 25 watts?

- You could for instance when one of these AP's using 9.5 watts (only) , connect to it just after it has booted , and issue

the command show logging , watch for messages related to power and or impact for 9.5 watts being available (only)

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Mark Elsen — Mon, 23 May 2022 10:35:31 GMT

- For ClientLink question , check if this thread can provide hints : https://community.cisco.com/t5/wireless/need-to-enable-client-link-feature/td-p/2709340

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Mon, 23 May 2022 10:37:49 GMT

The link is old ‎08-05-2015

I think Clientlink 4.0 was not there

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Flavio Miranda — Mon, 23 May 2022 11:20:29 GMT

When i check the power consumption that the AIR-AP2802I-E-K9 APs are using on the SG-300 switches i see that the AIR-AP2802I-E-K9 are only using 9.5 watts.

When these APs are using a power injectors then they use about 25 watts!"

This AP model requires at least 15.4W. You can check the doc attached. With 9.5 watts chances are they did not turn the radios on. Or turn on 2.4ghz on.

"What is the practical difference between 9.5 and 25 watts?"

The different is that using 9.5 you does not meet the minimum requirement to this AP to work properly. And using 25 you are above the requirement, which is good. AP will negociate, through CDP or LLDP, the power it needs exactly.

I did some Googling and find that the antennas number on an AP maybe affected with low wattage! is that right?

How and where to see the difference?

AIR-AP2802I-E-K9 model is 4x4 do they work like 1x1 with low wattage? where can i show this ?

We have thousands of laptops that are 2x2 so 1x1 is bad i think !"

That´s right but I dont belive is possible to see the difference. The AP has its power requirement and you need to attend it. If the power requirement is attended, it will hav full functionality inclusing all the antennas.

"When i check AIR-AP2802I-E-K9 i see that legacy beamforming is disabled, how to show that Clientlink 4.0 is enabled on AIR-AP2802I-E-K9 model?"

You can see it on the WLC cli:

(WLC1) >show 802.11a
.
.
Beacon Interval.................................. 100
CF Pollable mandatory............................ Disabled
CF Poll Request mandatory........................ Disabled
CFP Period....................................... 4
CFP Maximum Duration............................. 60
Default Channel.................................. 36
Default Tx Power Level........................... 0
DTPC Status..................................... Enabled
Fragmentation Threshold.......................... 2346
TI Threshold..................................... -50
Legacy Tx Beamforming setting.................... Enabled

Or per AP:

show ap config 802.11a "AP!
.
.
Phy OFDM parameters
Configuration ............................. AUTOMATIC
Current Channel ........................... 40
Extension Channel ......................... NONE
Channel Width.............................. 20 Mhz
Allowed Channel List....................... 36,40,44,48,52,56,60,64,149,153,157,161,165
TI Threshold .............................. -50
Legacy Tx Beamforming Configuration ....... AUTOMATIC
Legacy Tx Beamforming ..................... ENABLED

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Mon, 23 May 2022 11:32:58 GMT

On the 2802 AP model the WLC says:

Legacy Tx Beamforming Configuration ....... AUTOMATIC
Legacy Tx Beamforming ..................... DISABLED

I don't know if this is also Clientlink 4.0, but when i try to enable it i get:

(Cisco Controller) config>802.11a beamforming ap "APname" enable

Slot not disabled.

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Flavio Miranda — Mon, 23 May 2022 12:15:39 GMT

Probably you need to disable radios first before enabling the feature. Try to shud down the AP radios first and try to enable the feature after.

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Mark Elsen — Mon, 23 May 2022 12:24:17 GMT

Perhaps you need to stop the radio first, then execute your commans, and
start the radio again. M.

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Mon, 23 May 2022 13:34:30 GMT

I can now see that all my 2802 and 1852 APs have ClientLink disabled, is there any reason why it is disabled on these by default, while it is enabled by default on older AP models like 2702?

Any answer to first question about the wattage, i did restart one 2802 AP with low wattage but could not see any weird loggs?!

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Rich R — Mon, 23 May 2022 14:08:50 GMT

If it can run in degraded mode that's usually documented on the data sheet. Nothing shown for 2800 implying that it MUST have at least POE+ which means it's probably running with radios turned off (that is standard behaviour for low power).

https://www.cisco.com/c/en/us/products/collateral/wireless/aironet-2800-series-access-points/datasheet-c78-736497.html

Input power requirements		● 802.3at PoE+, Cisco Universal PoE (Cisco UPOE ^®) ● 802.3at power injector (AIR-PWRINJ6=)
Power draw		● 22.5W at the PSE (20W at the PD) with all features enabled except for the USB 2.0 port ● 26.5W at the PSE (23W at the PD) with the USB 2.0 port enabled

Compare to 1850 https://www.cisco.com/c/en/us/products/collateral/wireless/aironet-1850-series-access-points/datasheet-c78-734256.html

Power draw	● 20.9W Note: When deployed using a Power over Ethernet (PoE) specification, the power drawn from the power sourcing equipment will be higher by some amount, depending on the length of the interconnecting cable.
Powering options	● 802.3at ● Enhanced PoE ● Cisco power injector, AIR-PWRINJ4= ● Cisco local power supply, AIR-PWR-C= ● Cisco power injector, AIR-PWRINJ5= ( Note: this injector supports 802.3af only) ● 802.3af Note: If 802.3af PoE is the source of power, (1) the 1852e 2.4-GHz radio will shift to 2x3 from 3x4, (2) The USB port and AUX Ethernet port are disabled on both the 1852i and 1852e.

Re: AIR-AP2802I-E-K9 APs PoE diffrences

JPavonM — Mon, 23 May 2022 14:49:18 GMT

Have you checked your SG300 is a PP model? P-only models do not support PoE+ but only 802.3af.

Check the output from one of my SG300-10PP switches, showing AP3702 connected requiring 16.4Watts but only consuming 7 Watts at the moment.

sg300#sh cdp neighbors de
---------------------------------------------
Device-ID: sg300
Advertisement version: 2
Platform: cisco AIR-CAP3702I-E-K9
Capabilities: TransBridge SourceRouteBridge IGMP 
Interface: gi7, Port ID (outgoing port): GigabitEthernet0
Holdtime: 141
Version: Cisco IOS Software, C3700 Software (AP3G2-K9W8-M), Version 15.3(3)JPJ7, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (
Duplex: full
Power drawn: 16800 milliwatts
SysObjectID: 0.0
Primary Management Address: IP x.y.z.1,
Addresses:
IP x.y.z.1
IPv6  (link-local)
sg300#sh power inline 

Port based power-limit mode
Inrush Test: Enable
Legacy Mode: Enable

Unit Power Nominal Power Consumed Power Usage Threshold Traps Temp (C) 
---- ------- ------------- ------------------ --------------- --------- -------- 
1 On 62 Watts 7 Watts (11%) 95 Disable 58

HTH

Jesus

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Tue, 24 May 2022 07:16:15 GMT

Is there any command that shows how many radios are used?

If 802.3af PoE is the source of power, (1) the 1852e 2.4-GHz radio will shift to 2x3 from 3x4,

A command that shows if 2x3 or 3x4 are used!

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Tue, 24 May 2022 07:31:42 GMT

What i have is SG350-10MP

Don't have Show cdp ne details! only sh cdp ne

Version: 2.5.0.83

The question is what happens when using low wattage? is there any command that shows how many radios are used when using low wattage?

The attached shows my sh power inline

All these APs are 2802 model

Re: AIR-AP2802I-E-K9 APs PoE diffrences

JPavonM — Tue, 24 May 2022 09:02:00 GMT

From that screenshot you can see 16.8 Watt requested and only 6.8 Watt been used at the moment.

That matches 802.3af standard:

– Maximum 16.80 W at the PSE.

So you AP is not receiving PoE+ budget so it will behave weird, as Cisco does not support this scenario to disable radio chains if less power is received.

But Catalyst APs reduces radio chains or even disable radios if less power is received.

Re: AIR-AP2802I-E-K9 APs PoE diffrences

Moudar — Tue, 24 May 2022 09:09:15 GMT

We have already ordered about 150 Catalyst 9120 APs.

Do you mean that this model will not work at all if the PoE is not PoE+?

Re: AIR-AP2802I-E-K9 APs PoE diffrences

JPavonM — Tue, 24 May 2022 09:26:26 GMT

Yes they will work with 802.3af PoE. Check this from DS: