a little bit about my situation: so, I'm in the gifted computer science class in high school. We use internet everyday but we only have LTE in the areas with barely 20Mbit/s and to us, that just too slow. Therefore, we want something more than that. We did ask our school to share their network with us but there was no respone. So I came up with the idea that I could use multiple sim for larger bandwidth. I have 3 sim cards here (2 from the same internet provider) which mean I should have around 60Mbit/s.
The problems come, I discovered that when I use load balancing with 33.3% weight for each connection. When I use application, that app just load on 1 WAN connection and 2 other was ignored.
I think there is a solution where I could split the packet from that application to all 3 WAN, go to some server that can concat the packet again and then send them to the final destination. But I don't know what is the right keyword to search for this.
That is the inherent problem with load-balancing, a single client can never exceed the wan speed of a single uplink (~SIM card). Without cooperation from your ISP (or a (~your) server somewhere in a data centre stitching together the multiple LTE connections into one, via its WAN uplink) the only thing you can do, is either improving the situation for many concurrent clients (each limited by the maximum speed of a single SIM card) or a round-robin distribution of packets (which is strongly discouraged, as it breaks session tracking of your remote servers and may trigger security alarms).
Load-balancing (at least unassisted flavours) is tricky, even commercial routers usually get this wrong - so if you can avoid it, you can save yourself a lot of pain not going there (e.g. in the sense of one router per SIM, distribute your clients to each router fairly).
Instead of MPTCP or a service like Speedify that truly combines the connections, you can also try improving the load balancing settings.
This won't improve single streams of a download for example, but will improve speeds for things like Steam downloads that open many connections.
You'd have to add some extra mwan3 rules for ports that can be load balanced without any "stickiness", e.g. port 80.
In theory, this can be done exactly like you described it; there even existed a company that sold a router with one LAN port and several WAN ports, so you could merge the bandwidth from several ISPs.
You will need an external server (with enough bandwidth, of course), then create a VPN to that server over each internet connection, and finally bond the connections at both ends.
I would not have high hopes of this working, but if you already own the hardware, you can rent a VPS for cheap, and do some tests.
I didn't think about this case yet, but I think there is a solution, like if one wan not working or just slow af so the another wan have been done transmitting but that slow one is not. we could just use the WAN that already done transmitting to continue transmit data (?)
I have almost unlimited plan on two sim so my problem is just the speed of it, no need to balance the data usage on 2 sim
