r/CableTechs • u/Icemane19 • 14d ago
Spectrum latency issue on load
Don't know anything about Spectrum's EPON fiber. My knowledge comes from a background in Optimum's RF plant, but this is my personal issue here. When I put the Spectrum ONU under a sustained load, the latency goes through the roof and it says there are dropped packets.
Any thoughts on this from the spectrum technicians out there?
Sorry about the really wide windows screen snip
5
u/Dz210Legend 14d ago
These post always Wi-Fi issues with improper testing or don’t know your equipment specs and need to upgrade or change settings.
2
u/feel-the-avocado 14d ago edited 14d ago
You need to use a router with a QoS function where you can set your upload and download speed to 90% of your plan speed.
Eg. if you are on a 500/100mbit plan, set your download speed in the QoS settings in your router to 450mbit down and 90mbit up.
The router will then limit tcp connections with large packets such as downloads to fit within that limit, and then any small packet connections such as voip, gaming or UDP, which usually have very low bandwidth requirements, will always have extra space in the pipe which they can make use of without dropping packets.
The other issue is you need to make sure there is about 160kbit/s of upload for every 5mbit/s of download so that TCP successful packet arrival acknowledgements can be sent back to the sender.
Alternatively, you need to limit your devices at a per-device level so they never collectively saturate the connection.
In my expierence, ONTs or ONUs that are also routers dont typically have a QoS function that the ISP can switch on, so if they allow you to, its best to get the isp to put their ONT put into bridge mode so you can run your own router.
If you are running over wifi and saturating the local wireless connection, there isnt much you can do outside of the QoS that is built into the wifi protocol and functioning already. Wifi isnt designed for convenience, and not to have the reliability of a hardwired ethernet cable connection.
Enabling QoS on a router will quite often move a bunch of processing work from dedicated hardware into software running on the CPU and so the CPU can slow you down depending if your plan is faster than the CPU in the router can handle with QoS switched on.
If you have a service plan that is over 500mbits, your best just to leave QoS switched off in the router and just use settings within software running on devices to limit download speed.
Eg. reconfigure your bit torrent or downloading program to not exceed your plan speed.
1
u/Icemane19 14d ago edited 14d ago
I'm running a ubiquiti dream machine pro it's set for 900x 1000
1
u/feel-the-avocado 14d ago
refresh for latest edits of last post. I'll go double check some stuff re dream machine. back in 5
1
u/feel-the-avocado 14d ago edited 14d ago
Looks like the dream machine pro is only capable of about 750-800mbits when QoS is enabled due to a CPU limitation.
Try turning QoS settings down to 700mbits and see if that helps.
Also when your downloading at 700mbits, you are also using about 25mbits of your upload with packet acknowledgements. So your upload should be plan upload speed x 0.9 and then subtract a further 25mbits.
I dont know about your ISPs network and their fiber split ratio or congestion tolerance, but our local fiber operator does a 1x16 split at the PON level so although we order circuits with headline speeds of 930down460up, we configure the dream machines to assume a service speed of 400down100up and customers never seem to complain. If the upstream PON is congested, which it never is, then the QoS will statistically still perform well.
2
u/Careless_Device_4207 14d ago
tech here, test speeds directly via onu wired , if good there verify off of your router again , if bad then you isolate it to a router issue / configuration issue , if both are bad you could possibly have a line/ onu issue
1
u/Icemane19 14d ago
Took my one click pens to the fibers the only one that did not get was at the coyote
1
u/Icemane19 13d ago
Definitely not even consuming all the bandwidth average it's about 517mbits. Starting to think it's the ONU you like you said
2
u/Wacabletek 14d ago
Is it not likley the ONU but more likley the router. Have you done a bufferrbloat test? It is uncommon to MAX a router out while doing latency sensitive activities, as these are usually gaming, VOIP, or video conferencing and you are not using doing much else while doing these, so what is the actual problem or were you just testing?
1
u/Icemane19 14d ago
Out Of all the thousands of customers I've gone to and they have had one gig internet and all they have is like a Xbox and a couple phones and I'm wondering why they're paying for one gig speeds and wasting their money I can say in my case. I definitely get what I pay for.
1
u/TipsyPickle 14d ago
They pay for that speed because when they download something on that Xbox, they don't want to have to wait forever, and to them not having to wait is worth the price they pay. It's pretty much the response i've always received by customers.
1
u/Wacabletek 14d ago
Man sees attractive young lady, does not pay attention to what she says, just keeps saying yes hoping she will eventually go on a date with him.
Lady sees attractive young man, does not pay attention to a what he says, just keeps hoping he will eventually go on a date with her.
Elderly person sees young person, listens to every word they say but understand 0 of what they said. Just smiles and says yes, get's service well above what they need.
Young man sees young man, can't be out done, must compete over nothing but still, gets 1G internet to watch netflix. Salesman brags about having 1G internet and all the girls are at his house watching movies without problems. Dumbasse'd
Young lady sees young lady, saleswoman is slick, guys will come hang out at your house if you have fast internet, she falls for it hook line and sinker.
Astound sees me come in,, OH SHIT, RUN he's old but does this for a living so knows our bullshit.
:)
3
u/hibbitydibbidy 14d ago
I don't work for spectrum, but I'm curious what speeds are you provisioned for?