Menu
Reply
axing_product
  • 15
  • 1
  • 1
On our wavelength
1,018 Views
Message 1 of 23
Flag for a moderator

Slow Speed in Modem Mode

I have recently upgraded from the Hub3 /M350 package to Hub4/Gig1 package. I use the Hub in modem mode as I have an Netgear Orbi setup using a Cat6 wired backbone connecting the satellites and Cat6 wired connections to my devices. When running speed tests, I get random download results ranging around the 800 Mbps mark. I switched the Hub4 into router mode and ran a Samknows speed test with expected results to the Hub of 1057 and 873 to the computer. I ran the test several times with similar results. I ran the test using a Cat6 cable from the Hub 4 to my computer. Anyone know how I can improve the speed from the Hub?

Speed to Virgin Media Hub 4.jpeg

0 Kudos
Reply
Andrew-G
  • 9.53K
  • 1.54K
  • 4.56K
Very Insightful Person
Very Insightful Person
989 Views
Message 2 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

Do you want to offer examples of the speed range you're seeing modem mode, and details of how you are testing speed?

Not the cause of variable speeds, but worth also knowing that the Hub 4 has miserly 1 Gbps ethernet ports, the most you'll get through those (after allowing TCP/IP overheads) is in the high 800's to 950 Mbps range.  VM could have fitted it with at least one 2.5 Gbps port, but that would have cost an extra 5p, and they figured that them saving 5p was a better deal than you getting what you expected.

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

0 Kudos
Reply
axing_product
  • 15
  • 1
  • 1
On our wavelength
966 Views
Message 3 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

I ran a speedtest from my iMac and got this result. My sample has a range between 700 and 848 with an average of late 700's. The network path is Hub4 -> Cat6 Cable -> Orbi RBR50 router -> Cat7 Cable -> Orbi RBS50 Satellite -> Cat6 cable -> Ethernet port on the mac of my iMac Late 2015  

Screenshot 2021-05-12 at 13.44.32.png

I then ran another speedtest from my iPad Air 4 and got a slightly better result. This is fairly consistent compared to other tests I performed. The network path is Hub4 -> Cat6 Cable -> Orbi RBR50 router -> Cat7 Cable -> Orbi RBS50 Satellite -> Cat6 cable -> Gigabit switch -> Cat6 cable -> Ethernet to USB B adaptor -> USB B to USB C adaptor -> iPad Air 4

Screenshot 2021-05-12 at 13.46.58.png

 

0 Kudos
Reply
legacy1
  • 18.17K
  • 761
  • 1.88K
Alessandro Volta
939 Views
Message 4 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

Your iMac is slow then.

---------------------------------------------------------------
0 Kudos
Reply
axing_product
  • 15
  • 1
  • 1
On our wavelength
931 Views
Message 5 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

I'm able to copy a 5gb Windows 10 ISO file from my NAS drive to my iMac at acceptable speeds so no issues with throughput. I've attached a graphic of the transfer which shows bursts of +160 MB/s and an average around 130 MB/s. The connection between my NAS and iMac is via a gigabit switch using Cat 6 cables. 

Screenshot 2021-05-12 at 17.13.59.png

 

0 Kudos
Reply
axing_product
  • 15
  • 1
  • 1
On our wavelength
930 Views
Message 6 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

... and if anyone's interested, here's my BQM monitor. The red section is when I took the Hub 4 down last night to perform the speedtests in post #1.

 

axing_product_0-1620836238795.png

 

0 Kudos
Reply
SCA1972
  • 6.12K
  • 673
  • 2.14K
Very Insightful Person
Very Insightful Person
920 Views
Message 7 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

@axing_product What happens if you take the Orbi out of the equation and plug the iMac straight into the hub in modem mode?  I appreciate that the iPad was also going through the Orbi and got better results, but if the iMac isn't the bottleneck then maybe the Orbi is treating traffic from the iMac differently through some sort of QOS setting and throttling WAN speed.

The iPad results seem to me to prove that the hub is not slow in modem mode and the Samknows speed test shows that VM are delivering the correct speed to the hub.

______________________
Scott

My setup: VM TV box, M350 Fibre broadband with Hub 3 in modem mode connected to a Netgear R7000 router. Telewest/VM user since 2001.

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

0 Kudos
Reply
axing_product
  • 15
  • 1
  • 1
On our wavelength
916 Views
Message 8 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

Is plugging a Mac directly into a hub in modem mode a thing? I thought it needed a router to provide IP, routing instructions, etc.  I was able to connect directly when the Hub was in router mode which is where I was able to perform the Samknows speedtest in post #1.

0 Kudos
Reply
Roger_Gooner
  • 7.51K
  • 506
  • 1.39K
Legend
904 Views
Message 9 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

The modem gets a WAN IP address from the CMTS, and in the old days all you got was a modem from the cable operator or Openreach. The addition of a router provides LAN ports and, in most cases, WiFi.

--
Hub 3.0, TP-Link Archer C8, TP-Link TL-SG108S 8-port gigabit switch, V6
My Broadband Ping - Roger's VM Broadband Connection
0 Kudos
Reply
axing_product
  • 15
  • 1
  • 1
On our wavelength
899 Views
Message 10 of 23
Flag for a moderator

Re: Slow Speed in Modem Mode

Just tried plugging the mac directly into the Hub 4 in modem mode but didn't get an internet connection. Rebooted and still the same. Any specific instructions I need to follow?

0 Kudos
Reply