Reliable VPN between branches on which hardware to build?

Question

VPN

Given 1 head office and 4 branches
Two lines are connected to each office and branch, one with a speed of 10 Mb/s White static IP (legal entity) and one 100 Mb/s white dynamic IP (individual) Internet from one and the same provider, let's
call them channel 1 and 2, respectively
, at the head office we plan to install a VPN server and Asterisk
in each of the branches a router for accessing the Internet and also a VPN client
The task is to send internal document flow over channel 1 + print to a remote printer Send all non-
service traffic on channel 2 exchange of any files access to the Internet
Also need load balancing between channels 1 and 2
And finally, the most interesting thing At the head office, we plan to have another Internet provider (reserve) and the question arises how to make sure that if the connection with one of the providers is lost, remote VPN clients can still connect

Answer 1

Good afternoon,
If the issue of encryption is not worth it, then you can put MikroTik 1100AHx2 in the core if you need encryption, then start looking from the CCR model or you can try the new HEX model, they promise up to 500m / bit AES128 in it.
Reservation can be done using OSPF and different cost for interfaces (switching will take place no more than 10 seconds).
Balancing on channels of different widths is possible, but it will be implicit, using ECMP specifying gateways in proportion to the channel width.