Combine Network interfaces for stability

[Space Kite]

Hi, I am trying to combine 3 different sources of internet connection into 1. With the intention to minimize / negate any possibility of packet loss or disconnection, as I need to do very delicate tasks that require a steady 100% uptime connection with 0 packet loss.

I have 3 interfaces available, 2 of them are phones tethering 4g through USB and one is a wired ethernet connection. For reasons I don't want to discuss my ethernet connection is very unstable and the 4g tethering phones "reset" the connection every 20 minutes or so, probably changing IP which causes a disconnection from the tasks I am going through and due to the nature of the task I have to start it all over from the beginning, wasting time and resources.

I am not super educated on Networking but I know a bit from 2 decades of being on the internet an troubleshooting errors that I've encountered along the way, but I've never been face with a challenge of this nature. Please refrain from suggesting things like "hire a new ISP", "get a better router", "move to a different area", etc. The solution I am looking for is how to combine different connection/interfaces so that when one fails or takes too long for a request, another one kicks in. Thanks a lot in advance.

I've tried Bridging the 3 connections on windows but that doesn't seem to do the trick.

I changed the bridge ip to the ip that I had on the wired ethernet connection and it seems to only be using the ethernet connection, completely ignoring the 2 phones tethering through usb.

I know there is a software called "Speedify" that claims to do this through a VPN, as much as I would like that, it is nearly impossible to acquire that software from my country due to sanctions/restrictions by the government on payment processes etc. So I am left with this problem.

[BillBill]

14 minutes ago, Space Kite said:

Hi, I am trying to combine 3 different sources of internet connection into 1. With the intention to minimize / negate any possibility of packet loss or disconnection, as I need to do very delicate tasks that require a steady 100% uptime connection with 0 packet loss.

I have 3 interfaces available, 2 of them are phones tethering 4g through USB and one is a wired ethernet connection. For reasons I don't want to discuss my ethernet connection is very unstable and the 4g tethering phones "reset" the connection every 20 minutes or so, probably changing IP which causes a disconnection from the tasks I am going through and due to the nature of the task I have to start it all over from the beginning, wasting time and resources.

I am not super educated on Networking but I know a bit from 2 decades of being on the internet an troubleshooting errors that I've encountered along the way, but I've never been face with a challenge of this nature. Please refrain from suggesting things like "hire a new ISP", "get a better router", "move to a different area", etc. The solution I am looking for is how to combine different connection/interfaces so that when one fails or takes too long for a request, another one kicks in. Thanks a lot in advance.

I've tried Bridging the 3 connections on windows but that doesn't seem to do the trick.

I changed the bridge ip to the ip that I had on the wired ethernet connection and it seems to only be using the ethernet connection, completely ignoring the 2 phones tethering through usb.

I know there is a software called "Speedify" that claims to do this through a VPN, as much as I would like that, it is nearly impossible to acquire that software from my country due to sanctions/restrictions by the government on payment processes etc. So I am left with this problem.

I think for that to work effectively you would need 3 different IP addresses. Since you are using 3 devices. 

[Space Kite]

Just now, BillBill said:

I think for that to work effectively you would need 3 different IP addresses. Since you are using 3 devices. 

Each interface has a different IP address before bridging, once bridging you are not able to modify their IP addresses, you can only modify the IP of the Network Bridge device, which only has the possibility of having 1 IP (on IPv4). IPv6 also allows 1.

[thekingofmonks]

Unless the ISP speeds are fast, you're looking at a likely bottleneck from the bridge forcing the interfaces to wait for each other and making sense of packets. And possible slowdowns with the CPU since the bridge is software.

[Space Kite]

7 minutes ago, thekingofmonks said:

Unless the ISP speeds are fast, you're looking at a likely bottleneck from the bridge forcing the interfaces to wait for each other and making sense of packets. And possible slowdowns with the CPU since the bridge is software.

I'm not even sure what the function of the bridge is, to be honest, apart from allowing LAN connections with devices connected to each network. 

[Electronics Wizardy]

You basically need a server on the other end to make this work. Otherwise you have multiple public IPs and you can't just seamlessly switch the IP your sending data from typically.

 

Look up something like speedify, its made for this exact usecase.

 

1 hour ago, Space Kite said:

I know there is a software called "Speedify" that claims to do this through a VPN, as much as I would like that, it is nearly impossible to acquire that software from my country due to sanctions/restrictions by the government on payment processes etc. So I am left with this problem.

What country are you in?

 

What router do you have? Typically you want your router do this for you.

[Space Kite]

3 hours ago, Electronics Wizardy said:

You basically need a server on the other end to make this work. Otherwise you have multiple public IPs and you can't just seamlessly switch the IP your sending data from typically.

 

Look up something like speedify, its made for this exact usecase.

 

What country are you in?

 

What router do you have? Typically you want your router do this for you.

I don't want to get too much into sharing personal info but we don't have credit cards or many options to buy stuff online, even Paypal has huge fees... so... that's why I rule out paid software.

I have a generic tp-link with DD-wrt with 1 Wan port and 4 Lan... How could I connect my both 4g phones to it? I don't think it's possible and it wouldn't work for me, The router is already overloaded enough.

[BillBill]

11 hours ago, Space Kite said:

I don't want to get too much into sharing personal info but we don't have credit cards or many options to buy stuff online, even Paypal has huge fees... so... that's why I rule out paid software.

I have a generic tp-link with DD-wrt with 1 Wan port and 4 Lan... How could I connect my both 4g phones to it? I don't think it's possible and it wouldn't work for me, The router is already overloaded enough.

You could get a router that has Dual Wan ports. 

[Space Kite]

6 hours ago, BillBill said:

You could get a router that has Dual Wan ports. 

but how would dual wan ports help me when I'm using phones with USB tethering as network interfaces?

[Alex Atkin UK]

On 1/30/2025 at 1:04 AM, Space Kite said:

Hi, I am trying to combine 3 different sources of internet connection into 1. With the intention to minimize / negate any possibility of packet loss or disconnection, as I need to do very delicate tasks that require a steady 100% uptime connection with 0 packet loss.

In my experience this is not a easy problem to solve without something complex like MPTCP Router or Speedify.

I have multiple WANs and its caused more down time than I have ever had with just a single WAN.  The problem is if any WAN goes down, the router has to reload the firewall.  If one of the WANs is really unstable, I have to disable it entirely or the firewall constantly restarting makes the entire network unusable.  I partly solved this by having the 5G connection run off its own router, so my main router doesn't know if that connection is up or down and just assumes its always up.  This only works as I'm using it for failover rather than reliability.

[Space Kite]

13 minutes ago, Alex Atkin UK said:

In my experience this is not a easy problem to solve without something complex like MPTCP Router or Speedify.

I have multiple WANs and its caused more down time than I have ever had with just a single WAN.  The problem is if any WAN goes down, the router has to reload the firewall.  If one of the WANs is really unstable, I have to disable it entirely or the firewall constantly restarting makes the entire network unusable.  I partly solved this by having the 5G connection run off its own router, so my main router doesn't know if that connection is up or down and just assumes its always up.  This only works as I'm using it for failover rather than reliability.

Someone in a discord I asked mention MPTCP technology and suggested I run a VM to run it on linux and merge my networks from there but that is so far away from my technical knowledge

[Alex Atkin UK]

3 minutes ago, Space Kite said:

Someone in a discord I asked mention MPTCP technology and suggested I run a VM to run it on linux and merge my networks from there but that is so far away from my technical knowledge

Me too.  The problem is that bonding consumer broadband connections is a whole lot of hacks, they were never designed to work like this.

[whispous]

If stability rather than bandwidth is your goal, then I have some terrible news for you:

 

It won't magically know when a packet is about to be dropped, and re-route it.

[BillBill]

16 hours ago, Space Kite said:

but how would dual wan ports help me when I'm using phones with USB tethering as network interfaces?

A dual wan router supports 2 internet connections. USB to ethernet adapter. 

[Alex Atkin UK]

5 minutes ago, BillBill said:

A dual wan router supports 2 internet connections. USB to ethernet adapter. 

Many routers support connecting to phones over USB but phones are not designed to be tethered,hot spot 24/7 so its not recommended and may even turn off tethering when idle.

[Space Kite]

23 minutes ago, Alex Atkin UK said:

Many routers support connecting to phones over USB but phones are not designed to be tethered,hot spot 24/7 so its not recommended and may even turn off tethering when idle.

hmm I basically use my phone as tether 24/7 no problem but that's an interesting fact, I did not know that support usb tethering.

 

[Donut417]

2 hours ago, Space Kite said:

hmm I basically use my phone as tether 24/7 no problem but that's an interesting fact, I did not know that support usb tethering.

 

I have a Synology RT2600AC and it has support for this. I’ve never tested it however. 

[Space Kite]

4 hours ago, Donut417 said:

I have a Synology RT2600AC and it has support for this. I’ve never tested it however. 

is it a load balancing router?

 

[Donut417]

1 hour ago, Space Kite said:

is it a load balancing router?

 

Not sure. I haven't tried Teathering as my phone plan doesnt allow it. So I can test with 2 internet connections to figure it out. 

[Alex Atkin UK]

17 hours ago, Space Kite said:

is it a load balancing router?

 

Load balancing will generally make jitter worse, its really about boosting download speeds.

[Space Kite]

On 2/1/2025 at 2:06 PM, Alex Atkin UK said:

Load balancing will generally make jitter worse, its really about boosting download speeds.

D:

[ISharkI]

So to summarize:

• No "new" hardware because payment problems
• No "commercial" software because of payment problems
• Currently not enough knowledge about networking
• Tethering via USB>4G (2x)
• One "regular" ISP uplink
• 100% uptime and 0% package loss

If this is correct I have to agree with whispous... thats not possible and if you find a perfect solution go get a patent, 'cause a lot of people will pay money for a solution of the last point.

The main problem here is your uptime/package loss requirements. Sometimes sh*t happens and a package get dropped. Either because some stray electron hit's some routers ram or some excavator kills a cable. You can't get 0% over all time. You can try to minimize it but not eradicate it.

 

Could you please elaborate what kind of "delicate tasks" you do? Is it time sensitive, do you need reliable transport, do you play some games, use a webform to buy some x-coins or are you trying to operate someones brain around the globe,... ?

 

IF you are prepared to get down from those 100% and 0% numbers and accept for example 99.99999% (which would be something what a AWS or Azure could maybe offer you) there may be solutions like specialized hardware manufacturers.

 

But still if you don't want to buy specialized hard/software there is only one way to facilitate this: blood, sweat and tears (and maybe some hairs if you are prone to tearing them out in frustration) to learn the needed skills to implement it yourself.

 

If you are prepared to learn about this, I would do it similar like others already described

• Basically you would need an endpoint somewhere else to connect to
• have hardware on both sides (like an old pc, some router with the features you want)
• connect both sides via tunnels/vpn, one tunnel over each connection
• give each connection weights as to reliability, speed, etc and bond them together (this is the tricky part which needs much fiddeling or knowledge)
• use both devices as router on each end, one as ingress and one as egress

Still this would introduce lags due to needing to wait for packets, misordered packets, etc...

 

TL;DR; Either you need to invest a load of money or a lot of work because the holy grail is not for free....

 

Good Luck

 

Source: Working as Networking Engineer for ~15 years

[Space Kite]

On 2/17/2025 at 12:29 PM, ISharkI said:

If you are prepared to learn about this, I would do it similar like others already described

• Basically you would need an endpoint somewhere else to connect to
• have hardware on both sides (like an old pc, some router with the features you want)
• connect both sides via tunnels/vpn, one tunnel over each connection
• give each connection weights as to reliability, speed, etc and bond them together (this is the tricky part which needs much fiddeling or knowledge)
• use both devices as router on each end, one as ingress and one as egress

 

I like this answer very much. Basically if my connection drops I have to start all over sometimes, that's what I mean by delicate. I guess it's very similar to an online videogame where if your connection drops you have to put your credentials all over to gain access again, or even restart the game completely. Let's say I'm uploading a file to a server and if the connection drops or reset I have to start uploading all over from 0%. Also if I'm on a videocall with someone specially if it's related to work and I have packet loss the video might freeze and I have to go back on my words or ask the individual on the other end to repeat, etc. My problem is mostly packet loss/ connection resets (I can see the ADSL light on my modem turn off and then on after a few seconds).

So yeah I've been using 4g for tasks that are not so data intensive, even tho my 4g connection will reset arbirarily every 15-20 minutes (I believe this is dynamic IP or something, because I permanently use ping -t command on windows cmd and I can see the connection drop for 1 or 2 packets and then continue perfectly with 0 packet loss and it coincides with disconnections from my applications.) And I still use my modem connection for more data intensive tasks, uploading/downloading, patching remotely, etc. And I basically have to get lucky so the connection doesn't drop when I leave it working overnight. It feels like playing Russian roulette sometimes.

Can the endpoint be some other computer in my own house? I have 2 basic TP Link routers that I have set up with DDWRT (I am using one, the other one is a spare) so I have an extra computer and an extra router that I could use as a potential server or whatever it is that I need.

[ISharkI]

The other endpoint should be somewhere else outside your local network, e.g. a friends house in the city if their fiber network there is more stable? Otherwise any server on the internet which has a stable network connection should work. Lets call it "Server" for simplification

 

Basically you would be building a Tunnel from your home to the Server and use it like a VPN to have egress to the internet on the other endpoint. This way the game/website/whatever knows where to send traffic for you (the Server) and does not need to figure out which of your connections the source packet originated. That would be your task in this imaginary setup.

 

If you are prepared to read up on the topic a few starting points for your search: link bonding (or sometimes "link aggregation"), load balancing, NAT ("Network Address Translation"), GRE (if you want unencrypted tunnels), vpn (openvpn, wireguard, openconnect - if you want encrypted tunnels be aware performance with encryption might depend on the hardware you use).

 

Also I would suggest reading up (there are tons of tutorials) and getting familiar with linux command line, as the majority of software in this direction is unix/linux based (most likely your router is too)

[Donut417]

8 hours ago, Space Kite said:

It feels like playing Russian roulette sometimes.

If up time is that critical you may want to look in to business internet with an SLA, that should give you up times as close to 100% as you can get.