Question My internet is slow when not on vpn

[kaleem104]

A few weeks ago I noticed my internet is oddly slow, the experience was very reminiscent of dial up days. but I have 1 gig up and down bandwidth from my ISP. When I first started noticing it I was trying to draw random conclusions like: I went to alibaba and all of the sudden my amazon cart doesn't load and thought maybe something got downloaded to my computer. Ran an anti-virus scan and nothing comes up, I frantically checked other resources being used on the computer like cpu, memory, io and they are so under utilized I am pretty sure my computer can bench press me, the desk its on, run everything I am trying to and still tell me its bored and has capacity to do more. So I checked my phone and an old laptop and they had the same issues, at this point I realized the common denominator is my internet. So I turned off wifi on my phone and it was faster on cellular connection than on wifi. So I ran some speed tests and results were pretty disappointing. I proceeded to reboot my ISP provided router and that still didn't do anything. It was kind of late in the day and their support lines are probably closed. I randomly decided to try out the VPN that came with my anti-virus software and all of the sudden everything magically works. I did some speed tests when on and off VPN:
off VPN:
Download speed varied between 100 to 800 mbps and upload varied between 0.4mbps to 1.5mbps.
(even thought speed test says 140 mb, it still struggles to load things like my email or videos on youtube at anything above 144p resolution and still has to buffer)
Ping against sites I normally go to the results were: ~5ms for ones that have data centers near me and ~50ms for others.

on VPN:
Download speed consistently ranged around 550 +/- 20 and upload around 130 +/- 5
Ping test while on vpn ~50 ms for every site I tried (the vpn connects to another state about 600-700 miles away).



I repeated the process and testing a few times to make sure it wasn't a fluke and finally nailed the problem down. "My internet is slower and very unstable when not using vpn". Now the conclusion itself makes no sense to me, why would it be faster on a VPN? I am no network expert but shouldn't vpn speed be limited to: Total_bandwidth - some_overhead = bandwidth_on_vpn(limited to any caps on vpn). I have a solid theory but the why this makes sense has me out my depths. I wanted to get some opinions and see if I missed something obvious before I make an angry phone to my ISP.

TLDR; My internet is slow when not using a vpn and need second opinion before I turn into a raging male Karen calling my ISP.

 

[Aeacus]

Now the conclusion itself makes no sense to me, why would it be faster on a VPN?

Though to say. ISP can tell better. But my guess would be:

VPN off, connection goes something like this: your PC <-> ISP server <-> proxy server <-> target server.
There could be more than 1 proxy server in the chain, but all it takes, is 1 slow server, to slow everything down.

With VPN on, VPN server probably has better network algorithm, whereby rather than making the shortest connection (least amount of jumps between different servers), it instead makes fastest connection, thus skipping the slow server in the chain. This improves your connection speed as well.

You can look at it like driving a car, whereby you need to go from one edge of the city to another. Rather than driving straight through the downtown, at rush hour (shortest route), you instead go around, via autobahn/highway. Sure, distance is longer but with greater speed, overall time is less.

before I turn into a raging male Karen

FWIW: Male Karen = Ken.

 

[vpnforroobet]

There could be a few reasons why your internet is slow when not on a VPN. One possibility is that your ISP may be throttling traffic when it detects that you're not on a VPN. Another possibility is that the VPN service you're using may be overloaded or experiencing bandwidth issues.

If your internet is slow when not on VPN, try changing to a different VPN service or increasing the bandwidth of your current service. You can also try using a different connection (Wi-Fi instead of cable, for example) to see if that makes a difference.

 

[kaleem104]

Update: I did manage to get this sorted out. I ended up contacting my ISP via their online chat. Initially they had me run some speed tests and stuff and tried to dismiss it as "everything is good" but I kept pushing. Eventually their tech seemingly did something. It started working and has been good for few weeks now. The tech said he disabled IPv6 on my router. I have no idea how or why that fixed it. But at the end of the day, things are working and that is the only thing he said he did. Am I convinced that IPv6 was the gremlin haunting my internet? not at all. But happy to have it working reliably again and won't go stirring up the hornets nest.

 

[bill001g]

I must have missed this when it was first posted, maybe because someone responded I did not read it well.

Disabling IPv6 is a fairly common recommendation for many problems. The more common one would be it works fast on some site but other are slow or timeout.

This a variation of the path issue described in the first answer but it is not really a server it the ISP routers and the interconnects between these routers and other ISP routers. For whatever reason IPv6 does not have as good inter-connectivity between ISP. Not sure why they have been say ipv6 is the "future" of the internet for the last 20 years.

What likely happened is the VPN service you are using only uses IPv4. This allows you to use a different path to the VPN data center and then also uses IPv4 from that data center out to the internet. Very few vpn services support IPv6.

Not sure when or if the various ISP will ever fix IPv6. I tend to recommended everyone turn it off, only a tiny number of servers in asia only have IPv6 web addresses. Game console also sometimes use it but they mostly run ipv6 inside of a IPv4 tunnel since many ISP do not support IPv6