Testing 1Gb internet connection

[Marty_B]

Hi all,
I recently upgraded my internet service to 1Gb. While the service technician was present, he connected a network testing device to my modem that said that they were indeed getting 1Gb download speeds to my house. After the tech left, I ran some tests and can not get above about 350Mbs down. I have bypassed the Untangle FW and connected a windows computer directly to my modem and still cant get above about 350Mbs down. The computer that I am connecting is a 3Ghz I5 processer with 16Gb memory and or course a 1Gb network interface card. I also connected a Raspberry Pi 4 with the latest Debian/Raspberry PI OS and ran the same test with the same result.
The question I have is, what else could be limiting my speed? I am I missing something or is my ISP BSing me?

Thanks for your help.

[sky-knight]

There's a LOT to unpack here in what from your perspective likely seems like a very simple thing so bare with me.

Gigabit connectivity is hard...

Please let that sink in, I'll say it one more time...

Gigabit connectivity is HARD!

Why do I say that? Well, if the ISP can deliver gigabit to your home or business, that's one thing. But then your testing... and you see numbers that don't hit that magic 1000mbit.

First thing to remember is that Ethernet is generally only 80% efficient, so in your best case your real world tests are often 800mbit or so.

Then we have the worst part... NIC quality. There are buckets, absolute BUCKETS of crappy "gigabit" interfaces on the shelf that simply will not go any faster than 300-400mbit. Realtek practically flooded the market with them. Do you have one? I have no idea... but the reality that you have two devices stuck at the same limit is actually evidence that something else is wrong, but never forget that just because an interface claims gigabit doesn't mean you'll get it.

Finally, system engineering. This applies to both your Untangle and the systems that are communicating through it. That gigabit speed you want? It's exactly the same limit as a SATA cable! So unless your system is operating with NVME storage, your HARD DISK cannot keep up with gigabit in all cases. But again this limit generally puts you in the 800-900mbit connection range, not 350mbit.

Finally, beware of speed conversion issues. You say 350Mbps is about 44Mb/sec. 1000Mbps is 125MB/s. AND, beware of the testing sites you're using. Speedtest.net is well known, but it's scientifically trash. It's a site designed to sell you stuff, it's not accurate in the least bit. It's NORMAL to require multiple machines to saturate a 1gbit line. Which is why I find all this gigabit ISP junk hilarious. In the US you cannot make effective use of any connection faster than 200mbit in many places. So it's entirely possible that the speed limit you're seeing is some bottle neck on the Internet between your equipment and the testing site. Your best bet is to download something that's well supported on a CDN. Kernel.org is a great place to start, go snag a copy of the Linux kernel source and see how quickly that transfers, multiply by 8 and see if your real speeds are in the right ballpark. Again anything > 800mbit is "working", sometimes the best I can do is 700... It all depends on everything in this little book I just typed.

[Marty_B]

Thanks Rob, for your thorough answer. Everything that you said makes perfect sense. I just wanted to hear it from someone that I trust. I have read enough of your posts on here to trust that you know what hell you're talking about. I suspect crappy nic cards in my computers.
I do have a good quality 10Gbs switch that I plan on using to test 3 PCs at the same time, all running different testing methods at the same time to try to saturate my modem. Thanks again for taking the time to help.

[sammy_cda]

It would be interesting to to to fast.com and see what Netflix says you are getting?

[Marty_B]

I will let you know.

[theoak]

Do you have QoS set?

I had a "friend" (ahem) ... that had an embarrassing moment where their internet was 30/2 and they upgraded to 300/30. This "friend" had QoS set to something like 26/1.5. When the new internet was installed all this "friend" could get was 26/1.5. This "friend" calls tech support and was on hold before they finally realized they still had QoS set for the old internet speeds. After changing the QoS settings to 300/30, indeed the full speeds were realized.

Some peoples "friends"

[sky-knight]

Do you have QoS set?

I had a "friend" (ahem) ... that had an embarrassing moment where their internet was 30/2 and they upgraded to 300/30. This "friend" had QoS set to something like 26/1.5. When the new internet was installed all this "friend" could get was 26/1.5. This "friend" calls tech support and was on hold before they finally realized they still had QoS set for the old internet speeds. After changing the QoS settings to 300/30, indeed the full speeds were realized.

Some peoples "friends"

Well if your "friends" are like mine, then I'm just going to translate "friend" to be "anyone that's ever used QoS on anything ever".

Because seriously, we ALL do that at least once.

[defcomllc]

Here in the Philadelphia region we have almost all our clients and my shop on VerizonFIOS business fiber 1Gb internet with static ip and Untangle NG Firewall. We have no issues getting well over 940Mbps up and down at all of these locations when running www.speedtest.net on a Windows PC plugged into our switches with cat6....All our NG Firewalls are running on my custom built SuperMicro 1U Intel XEON 4c/8t with 8 or 16gb ram and 256GB Samsung SSD. AND 1GB or 10GB Intel NIC's..

So I can tell you NG Firewall is not limiting us and VerizonFIOS business 1GB plan is providing over 940Mbps both up and down. In all instances....

[Marty_B]

Thanks for the replies everyone. I am not really concerned about the Untangle limiting me, I am more concerned that my other older hardware is the limiting factor. As I said, I connected directly to the cable modem and still am not getting satisfactory throughput. If, however I am satisfied that Spectrum is indeed supplying the advertised speed to me, that will be the end of story. I also have a friend that was bitten by the QOS setting before, just not this time. . If I am getting 1Gb to my switch and that gets divided up at my switch to all of the other bandwidth hungry devices on my network, I will be OK with that. I plan on doing some more testing this weekend. I will post the results.

[balrog]

Thanks for the replies everyone. I am not really concerned about the Untangle limiting me, I am more concerned that my other older hardware is the limiting factor. As I said, I connected directly to the cable modem and still am not getting satisfactory throughput. If, however I am satisfied that Spectrum is indeed supplying the advertised speed to me, that will be the end of story. I also have a friend that was bitten by the QOS setting before, just not this time. . If I am getting 1Gb to my switch and that gets divided up at my switch to all of the other bandwidth hungry devices on my network, I will be OK with that. I plan on doing some more testing this weekend. I will post the results.

you probably have done this and mentioning it for completeness. you can do an internal network test first to eliminate potential network or desktop hardware and create a baseline. then do a speedtest or fast.com(preferred) on the internet.

an iperf3(pure network internal speed test) from untangle router or desktop(iperf3 client) to raspberry pi (iperf3 server). My synthetic network speed from untangle(intel i5) to raspberry pi internal is around 921mbps.

[Marty_B]

you probably have done this and mentioning it for completeness....

Thanks have done some cursory tests internally. I am unfamiliar with Iperf3, but will look at it this weekend. Thanks for the suggestion.

[Marty_B]

I was able to borrow an Optiview XG and confirmed that my throughput issues are due to my nic card. Any recommendations on a good quality NIC?

[sky-knight]

And once again I repeat the mantra...

Go Intel, or go home!

Seriously... pick one, for the most part they all work.

[Marty_B]

Thanks again for everyone's help. Intel it is!

[Marty_B]

Just a follow up, Iperf3 has become my new best friend. I now have it running as a daemon on a raspberry pi 4 sitting right next to my main switch. I also have a few other small utilities running on it to make my network checks quick and simple.
I replaced two of my NICs with Intel NICS and now get throughput above 900Mbps routinely. Thanks balrog and Rob and everyone else for your insight.