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I am currently using 1G service from Xfinity but will be switching to Quantum fiber next week - that will entail using a mesh network they will install and my Arris wifi cable modem will no longer work with the fiber service.  I’ve been using a wired connection for my office computer and wanted to see what will change when it goes to a wireless (mesh) network after the fiber is installed.  So, I ran some tests comparing the wired and wireless speeds from my current SBG 8300 cable modem.

What I see is that I get 924/42 speeds from the wired connection and 380/41 from the wireless connection.  The wireless test is using the 5G connection with my computer sitting 6 feet from the modem and no other devices currently being used.  I also tested my speed in my basement using the 5G network and it also shows around 400/40.  Presumably the 5G connection should be getting about double that - and I do get double with the wired connection.  So, my question is why the wireless connections are so much slower?  The speed coming into the house is close to the specified 1G service (verified from the wired connection) and the cable wifi modem claims to support speeds over 1G using the 5G connection, but I seem limited to around 400 Mbps even when sitting next to the modem.  What is limiting that speed?

Ideas will be appreciated.

I’ll add to my previous question - perhaps it may engage some interaction.  Further investigations have revealed that the manufacturer of my wireless antenna says that their lab testing with the Arris wifi modem, can only achieve speeds of 600 even though it claims to handle speeds twice that.  I know all the caveats about interference, channels, multiple points of network connections, etc. but I am beginning to believe that the stated speeds for all wireless products are exaggerated, and in fact, not achievable.  Can anybody speak to whether they have found the stated wireless speeds actually capable of being achieved?


Since you are experiencing with Wi-Fi slow speed, I would suggest changing the channels and monitor the performance for 24hours.

http://arris.force.com/consumers/articles/General_FAQs/SBG8300-Changing-the-Wi-Fi-Channel


I can’t seem to login to the web manager to change the channel.  I never changed the password from the original (password) but it says that the credentials are invalid.  In addition, when I try to access the web manager, I tried Firefox, Chrome, and Edge and all 3 give me the warning that the version I am using is unsupported (they are all current versions).  I suspect that may be why the password is not being accepted.


Despite my inability to enter the manager, I read through the instructions and it seems like restarting the modem should enable it to find the least congested channel anyway.  So, I did that and the speed is unchanged - around 350 Mbps on wifi, 900 on wired.  Given that I am in the same room as the wifi modem, that no other devices should be interfering, and the fact that these speeds are the same when I try multiple devices on any of the 3 floors of my house, I am beginning to wonder if the device is really capable of achieving 900 (let alone the specified speeds) Mbps.  Can you confirm that it has achieved those wifi speeds in laboratory conditions - and, if so, what was the setup used to achieve that?


SBG8300 is compatible up to 1Gbps. If you are unable to login the GUI web portal, I would suggest to factory reset the modem.

After factory reset, all the customized credentials will be change to default settings, you can customize it again.

http://arris.force.com/consumers/articles/General_FAQs/SBG8300-Factory-Reset

http://arris.force.com/consumers/articles/General_FAQs/SBG8300-Changing-the-Wi-Fi-Name-and-Password

Once you logged in, I would suggest changing the Wi-Fi channel and monitor the performance for next 24hours.

http://arris.force.com/consumers/articles/General_FAQs/SBG8300-Changing-the-Wi-Fi-Channel


I managed to remember my password and I ran the suggested spectrum analyzer.  I am on the 5G network and all of the checks I ran gave me “no logs.”  The 2.4G network had some listings, but that is not the network I am connected to.  So, it doesn’t look like the channel is the problem.  I’ll repeat my question:  is it really possible to get 800 Mbps over the wifi 5G network?  If so, how do I do that?


I’ll add to my previous question - perhaps it may engage some interaction.  Further investigations have revealed that the manufacturer of my wireless antenna says that their lab testing with the Arris wifi modem, can only achieve speeds of 600 even though it claims to handle speeds twice that.  I know all the caveats about interference, channels, multiple points of network connections, etc. but I am beginning to believe that the stated speeds for all wireless products are exaggerated, and in fact, not achievable.  Can anybody speak to whether they have found the stated wireless speeds actually capable of being achieved?

All speeds specifications mention “up to”, the highest speed is usually in perfect condition, no wi-fi interference, and no load on the client devices.  I wouldn’t say they’re exaggerated but what the product can do.  Your mileage may vary.  

 

You’ll need to check the Wi-Fi specs on the client device along with the Speed and signal quality on the Wi-Fi status of the client device when it’s connected.

 

 

 


You can probably use the SBG8300 with the new fiber service when it’s set in a router mode.  You’ll just connect an Ethernet cable from SBG8300 Eth 4 to Fiber ONT.

 

SBG8300: Wi-Fi Router Mode


Interesting:  when I look at the wifi status on my device, it looks just like yours (slight difference in speed).  Is that speed the speed going into the router or coming out of it? If it is the latter, then it seems strange that when I run a speed test, it shows less than half the download as what the status screen is showing.

Also, the “up to” language isn’t quite adequate from my point of view - unless it can actually be achieved.  Given the realities of different equipment, interference sources, etc. I understand that no speed can be promised.  But the testing I have done is so far away from what is advertised and I’ve eliminated so many of the potential caveats, that I am skeptical about the “up to” language.  Now, if my wifi status is actually measuring what is coming out of the SBG8300 and my speed test is showing far less speed, then something else is at work and I am at a loss about what that could be.


The more I learn the stranger this gets.  The wifi status shown above is apparently a measure of the maximum capability of the connection between the router and the client device (my desktop).  It does not measure the actual speed obtained when accessing websites - the various online speed tests measure that.  OK, fine so far.  But then it gets strange.  My wifi status is similar to what you show above 800-900 Mbps and I have 1G service from Xfinity.  When I run the speed test, I am getting around 350 Mbps on wifi and 850 on ethernet.  But the difference between the 2 should only involve the connection from my router to my desktop - the connection from the router to the website is the same in both cases.  So, if the router-website speed is the same, and if the router-desktop wifi is capable of getting 850, and if the speed test shows 850 over ethernet, why do I only get 350 from wifi. 

 

It sure sounds like something to do with the Arris Surfboard, doesn’t it?


You are correct, the speed is the max capacity connection with the router and the client.  It could be the SURFboard device, it could also be the load on your PC, or the load on the Wi-Fi band.  I normally check the speed on the Wi-Fi adapter to check where the bottle neck is happening.  I don’t bother running speedtest from Wi-Fi client since I have many Wi-Fi connected to the network throughout the day.