Motorola MC3190 dropping packets

srosenthal · ‎10-05-2018

I have a warehouse with 3700 AP's all using only 5GHz with 2.4GHz disabled. In the warehouse we use both the MC3190 and MC32N0 scanners. I am getting a lot of complaints about network issues by users of the MC3190 scanners. When I run link tests to any of the MC3190 scanners I am seeing packet loss and only to a few of the MC32N0 scanners.

The MC3190 is 802.11a/b/g and the MC32N0 is 802.11a/b/g/n. I also noticed that all of the MC3190 scanners are showing CCXv4 and the MC32N0 scanners show CCXv1 with a few showing CCXv4. I see that all the scanners that I have performed a link test to that drop packets are all showing CCXv4. Not sure if that matters.

The 5GHz network is configured on the WLC for 12 and 24 Mbps as Mandatory with all speeds below 12 disabled, and all others supported. As of now only channels 36-64 and 149-161 are enabled but we are going to enable the Extended UNII-2 channels in the future once we get the scan guns configured to use those channels as well, which has to be done first. The SSID current has both WPA (TKIP & AES) and WPA2 (AES) configured.

I also noticed that on clients with CCXv4 show a "Ping Test" results window when I click on the Link Test button and when I click on the Link Test button for CCXv1 clients it shows a "Link Test" results window.

Thanks for the help.

Leo Laohoo · ‎10-06-2018

Seth,
Let's "dumb" this down.
1. Don't use UNII-2. Configure only UNII-1.
2. Try with only 20 Mhz channel bond.
See how this works.

srosenthal · ‎10-06-2018

This location is out in the country with no nearby sources of interference that would affect the use DFS channels and the scan gun manufacturer says they support the use of all 5GHz channels. Isn't it better to have more channels to provide greater channel diversity and reduce channel overlap?

We are already using single 20MHz channels and are dropping packets.

Leo Laohoo · ‎10-06-2018

@srosenthal wrote:

the scan gun manufacturer says they support the use of all 5GHz channels. Isn't it better to have more channels to provide greater channel diversity and reduce channel overlap?

Some manufacturer deliberate won't provide specific details. They'll say the product will support "all channels" but they, sometimes, don't. In regards to 5 Ghz channel, the more channels the scanners scan, the shorter the battery life. Try enable the UNII-1 only channels for a week.

Data Rates, enable all of them and see if this improves things or not.

By the way, these are the same guns that operate in the old Windows CE (and not Windows 10 CE), right?

srosenthal · ‎10-06-2018

These do use Windows CE 6.0.

They have their minimum power at the default of -10dBm and I will set it to 8dBm as I noticed the signal levels are lower than I would like them to be. Most of the AP's are running at below 8dBm currently.

I am guessing that by enabling the lower data rates would help to reduce re-transmissions but wouldn't it also keep the guns from connecting to a closer AP?

Leo Laohoo · ‎10-06-2018

@srosenthal wrote:

These do use Windows CE 6.0.

They have their minimum power at the default of -10dBm and I will set it to 8dBm as I noticed the signal levels are lower than I would like them to be. Most of the AP's are running at below 8dBm currently.

I am guessing that by enabling the lower data rates would help to reduce re-transmissions but wouldn't it also keep the guns from connecting to a closer AP?

1. Don't confuse Motorola WiFi business unt is the same (company) as the bar code scanner business unit. They are separate business entities and they hardly talk to each other.

2. Enable the low data rates because the chips of these scanners don't really like "talking" in high data rates.

Very different to the newer Windows 10 CE model. We were testing one and these roam very, very well.