TCP protocol

[janclaes47]

I posted elsewhere that 3BB VDSL seemed to block my VPN usage, because when I tested on my Android device the speed would be much lower than on a 3BB ADSL connection at my friends house.

 

I use a paid VPN and connect to Singapore server to test speed to UK with testmy.net.

 

The strange thing was that while my friends direct speed to Singapore is considerable lower than mine, the test speed to UK with Singapore VPN enabled would be more than double.

 

I then discovered that on my PC I would get good speeds with the same VPN enabled to the same Singapore server.

 

The VPN on both my PC and on the Android device use openvpn protocol by default, but this can be changed to TCP or UDP, and are both connected by wired LAN.

 

Today I started playing with the different protocols on my Android device, and where Openvpn and UDP would give a very bad test result, enabling TCP would more than triple my test results.

 

All test are performed connected to the same VPN sever and testing to the same UK server.

 

Is there anyone who can explain this, because my understanding in this is that for best speed using a VPN Openvpn is the preferable protocol, followed by UDP.

 

So why in my case does TCP give me triple the speed to the other 2?

[muratremix]

I can use openvpn udp on port 1194 (default, can be blocked easily if they want) on 50/20 vdsl and they never block my vpn.

I never like commercial VPN providers, I don't trust them. 5$ / month singapore digitalocean VPS is all you need.

[janclaes47]

1 minute ago, muratremix said:

I can use openvpn udp on port 1194 (default, can be blocked easily if they want) on 50/20 vdsl and they never block my vpn.

I never like commercial VPN providers, I don't trust them. 5$ / month singapore digitalocean VPS is all you need.

 

You have mentioned your VPS in another thread.

 

Can you use a VPS to connect to IPTV servers abroad that are not controlled by yourself or the VPS provider?

 

My understanding is not, but I'm gladly proven wrong if that is, so it is no use for me.

 

How do I change a port on an Android device?

 

My understanding is also that it is even easier to block TCP protocol.

[muratremix]

1 vps = 1 ip = 1 country.

However, you can use smart dns providers on top of vps/vpn (singapore) to get maximum speed if they still work fine.

 

TCP is easier to block and throttle yes.

Why are you getting 3x speed in tcp is beyond my imagination (it shouldn't happen)

[maxpower]

@janclaes47

 

You are dealing with only two protocols TCP and UDP. OpenVPN can run over either.

Very much simplified - UDP is stateless and just gets on with sending the data no matter what. TCP get more involved and makes corrections if bits of data are lost. This is why in theory UDP is faster.

TCP can be faster than UDP and this is all down to whats going on downstream to make bandwidth more efficient. Buffers can really throw a spanner in works when testing protocol speeds.

 

You should read up on the two protocols and get a little understanding of why and where they are used. There are situations where UDP is a really bad idea and the same goes for TCP.

Edited August 9, 2017 by maxpower
226

[janclaes47]

44 minutes ago, maxpower said:

@janclaes47

 

You are dealing with only two protocols TCP and UDP. OpenVPN can run over either.

Very much simplified - UDP is stateless and just gets on with sending the data no matter what. TCP get more involved and makes corrections if bits of data are lost. This is why in theory UDP is faster.

TCP can be faster than UDP and this is all down to whats going on downstream to make bandwidth more efficient. Buffers can really throw a spanner in works when testing protocol speeds.

 

You should read up on the two protocols and get a little understanding of why and where they are used. There are situations where UDP is a really bad idea and the same goes for TCP.

Yes I actually did read up and that's why I'm confused, because Openvpn is supposed to perform better than either TCP or UDP, but from the last 2 UDP should be the better option.

 

On my PC the VPN protocol is set to Openvpn, and I get decent speeds, that's why i don't understand why on the Android device on the same network this protocol is not working the same way.

 

May be you could give me a hint or a link why in certain situations UDP is a bad idea and in others TCP, as I have no idea where to start looking for that.

 

These are the settings available in both the Windows and Android app, and an explanation from my VPN provider. In the Openvpn protocol I don't have a choice between TCP and UDP.

 

 

[KittenKong]

2 hours ago, janclaes47 said:

Yes I actually did read up and that's why I'm confused, because Openvpn is supposed to perform better than either TCP or UDP, but from the last 2 UDP should be the better option.

 

You should re-read the explanation you were given which was correct.

 

OpenVPN is just the client. It will use TCP or UDP protocol according to the settings you give it (though on your phone you may not have a choice).

 

As explained, TCP is slow and reliable and UDP is faster and not so reliable. Use UDP when the accuracy of the data is not important but the speed is (ie video streaming). I'm surprised that the difference should be as much as three times though. That may indicate some sort of data corruption problem.

[janclaes47]

4 minutes ago, KittenKong said:

 

You should re-read the explanation you were given which was correct.

 

OpenVPN is just the client. It will use TCP or UDP protocol according to the settings you give it (though on your phone you may not have a choice).

 

As explained, TCP is slow and reliable and UDP is faster and not so reliable. Use UDP when the accuracy of the data is not important but the speed is (ie video streaming). I'm surprised that the difference should be as much as three times though. That may indicate some sort of data corruption problem.

I'm not using a phone but an Android set top box, and have no option to select TCP or UDP in the openvpn settings.

 

I also don't have that option on my PC.

 

TCP doesn't actually increase my speed, it gives me the same speed I get on my PC, which I assume is the correct speed since it is comparable with the result I got while still on ADSL and what I get at my friends location who is on 3BB ADSL.

 

It is openvpn and UDP reduce my speed to only about 30% of what I should get.

[KittenKong]

2 hours ago, janclaes47 said:

I'm not using a phone but an Android set top box,

 

It makes no difference.

 

 

2 hours ago, janclaes47 said:

I also don't have that option on my PC.

 

It would depend entirely on what software you use for the OpenVPN client. Some have those options, some dont.

[janclaes47]

My VPN provider answered me that my ISP probably throttles UDP port 1194, which would explain why my speed is low on UDP and not on TCP, but still strange that Openvpn works on my PC.

 

Any way, can I just forward port 1194 to any other port in my router to solve the problem?

[johng]

My VPN provider answered me that my ISP probably throttles UDP port 1194, which would explain why my speed is low on UDP and not on TCP, but still strange that Openvpn works on my PC.
 
Any way, can I just forward port 1194 to any other port in my router to solve the problem?

No I dont think it works like that the VPN server at the other end would still be sending/recieving on port 1194

They may have alternative non standard ports setup to try and bypassing blocking or throttling ask the VPN provider.

Sent from my ASUS_Z00LD using Thailand Forum - Thaivisa mobile app

[janclaes47]

9 minutes ago, johng said:

No I dont think it works like that the VPN server at the other end would still be sending/recieving on port 1194

They may have alternative non standard ports setup to try and bypassing blocking or throttling ask the VPN provider.

Sent from my ASUS_Z00LD using Thailand Forum - Thaivisa mobile app
 

On my PC the speed result is same as on the Andoid box. Horrible when selecting UDP and about double when selecting TCP.

 

The only difference is that with Openvpn selected on the PC the speed result is excellent, while on the Android box it is very bad.

 

So I went to look in the Openvpn log on my PC and it looks as if it reject UDP1194 port and switches to UDP443 port.

 

The question then is of course why it doesn't act the same on the Android box.

 

So could maybe a port forward from UDP1194 to UDP443 on my router solve the problem?

 

 

 

[johng]

You could try to access the Open VPN config file on the android box and edit it to use UDP protocol on port 443

 

Or forward port 443 UDP to 1194 but only from openvpn ip to Android box ip addresses ,forwarding 443 for everyone/from everywhere might break something else ?

 

 

 

[janclaes47]

6 hours ago, johng said:

You could try to access the Open VPN config file on the android box and edit it to use UDP protocol on port 443

 

Or forward port 443 UDP to 1194 but only from openvpn ip to Android box ip addresses ,forwarding 443 for everyone/from everywhere might break something else ?

 

 

 

Thanks for trying to help.

 

I will post some more screen shots from speedtests and logs below, please have a look at them.

 

I have installed Openvpn client on PC and Android, and use the VPN now through the Openvpn client.

 

It shows that UDP 1194 is used on both PC and Android, but on the Android UDP get throttled and on the PC they don't seem to succeed

 

1 . Openvpn connection log PC

 

2. Speedtest to UK with Singapore VPN enabled on PC

 

3. Openvpn connection log Android

 

4. Speedtest to UK with same Singapore VPN server enabled on Android

 

5. Speedtest to Singapore without VPN on Android

 

[janclaes47]

1 hour ago, janclaes47 said:

Thanks for trying to help.

 

I will post some more screen shots from speedtests and logs below, please have a look at them.

 

I have installed Openvpn client on PC and Android, and use the VPN now through the Openvpn client.

 

It shows that UDP 1194 is used on both PC and Android, but on the Android UDP get throttled and on the PC they don't seem to succeed

 

1 . Openvpn connection log PC

 

2. Speedtest to UK with Singapore VPN enabled on PC

 

3. Openvpn connection log Android

 

4. Speedtest to UK with same Singapore VPN server enabled on Android

 

5. Speedtest to Singapore without VPN on Android

 

 

I should add that I'm confident that the Android device itself is not the problem, because if i take it to a friends pace near here who is on 3BB ADSL 18Mb, the VPN works perfect.

 

I have also tried 3 other Android devices, and they all perform the same.

 

Before they switched me to VDSL the VPN also performed perfectly on the same Android device.

[ukrules]

Did you solve this in the end?

 

I hear some routers themselves can cause slowness when using a VPN in UDP mode.

 

 

[janclaes47]

3 hours ago, ukrules said:

Did you solve this in the end?

 

I hear some routers themselves can cause slowness when using a VPN in UDP mode.

 

 

I have since upgraded to fibre, and no problems there.