networking - Two internet connection, two routers , one home network

I have two 3G routers with their respective internet connection. One internet connection gives me a public IP, so I want to use it for accessing my home network from outside, while the other internet connection has faster speed so I want to use it for all outbound internet activities.

1. Which one of the router should be used as DHCP server?




2. Will the router with DHCP server become my internet connection for all outgoing requests?




3. How do I handle the port forwarding for accessing the internal devices from outside, if the router with public ip is not the one with DHCP server enabled?




4. How do I route all outgoing traffic via the router with high speed?

Answer

1) Assuming both routers run 24/7, it doesn't matter which one runs the DHCP Server.

2&4) You can set which Router should handle outgoing requests by setting the IP of the standard gateway to the IP of the desired router. (You need to do this for every machine in you LAN)

3) For that you need to set up NAT on on the desired router. NAT doesn't necessarily need to be on the same device than the DHCP Server.