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23 Messages

Friday, December 9th, 2022 12:37 AM

ATT BGW-320-500 keeps cycling network speed to 100Mbit on a 1000Mbit LAN

Hello - I have the ATT ONT BGW-320-500 Fiber Optic Gateway. 

In the past few days - I have been noticing my LAN Speeds are downgrading from 1000MBit to 100MBit on all ethernet Devices.   I am a IT Professional Myself, and here is what I have done thus far:

Power Cycled the Gateway ONT itself.  waiting 2 minutes between power cycle. = no change
Retarted all Devices on ethernet full power cycles. = no change
Checked all Ethernet Connections against various Cables ( Cat 6 or better on all ) = no change

Ran Full Diagnostics on the ONT - no errors multiple times in the last 3-4 days
Speed Test on the ONT repeatedly reports 1000 (+/- 20-40 MBit ) in speeds.  Multiple tests in the last day and prior back to 4-6 months ago. Side note: the upload test seems to be failing as of last night and today.

Here are the last 8 tests from the ONT Page:

Test HistoryTest Completion Time 	Direction 	Throughput(Mbps) 	Overhead 	Average Latency(ms)12/08/2022 19:26:24 	downstream 	1008.604 	70 	15.80812/08/2022 19:22:53 	downstream 	1020.35 	70 	7.96404/18/2022 16:20:24 	downstream 	1020.316 	70 	6.0904/18/2022 16:20:11 	upstream 	1012.544 	70 	7.99502/03/2022 06:48:59 	upstream 	1012.684 	70 	12.15302/03/2022 06:42:17 	upstream 	1013.279 	70 	11.90509/24/2021 13:33:16 	downstream 	1020.457 	70 	6.26609/24/2021 13:32:54 	upstream 	1014.864 	70 	7.157


Web Based Testing typically reports anywhere from 880-940 Mbit in both directions from overhead processing.  but after 12-24 hours and the repeated downgrade of the link, it immediately pegs to 100MBit both directions.

I noticed quite a few other posts concerning this behavior, is there a possible issue with the Firmware where LAN negotiation is misinterpreting or forcing a downgraded link?

Even forcing my devices on manual Full Duplex 1000Mbit the router refuses to stop this behavior.

ACE - Expert

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34.7K Messages

1 year ago

First, can you confirm that the clients do, in fact, have a downgraded link, or is the physical link still 1000/1000 and the bandwidth reduction is happening for some other reason?

You can check the Gateway side after you're having issues by looking at the Transmit Speed for the appropriate port under the LAN Ethernet Statistics on the Gateway's Home Network page (http://192.168.1.254/cgi-bin/lanstatistics.ha) and ensuring that it's still 1000000000 and not 100000000.  Windows has the ability to show you the physical link speed as well.

Community Support

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230.7K Messages

1 year ago

Hey @JMcCloud. We understand you need to check your internet provisioning and investigate why your internet speed slows down on Ethernet connected device. We'd be happy to look into this for you.

 

In order for us to further help with your internet speed slowing down, we'll need to meet you in a DM and gather some information to take a closer look for you. Please check your Direct Message Inbox (it’s the chat icon next to the bell icon in the upper right corner of the Forums).

 

We look forward to hearing from you. 
 
Olajide, AT&T Community Specialist
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