When the Fibre Fails: an animated side-by-side of load balancing (typical SD-WAN) and connection bonding in an office with three people and three carriers. When the fibre is cut, load balancing drops the call, fails the upload and loses unsaved work (0 of 3 working); bonding keeps all three working. Made by Munir Kotadia. Full description, screenshots and options: All the work, described.
One office, three people at work, three connections from three different carriers. Then the fibre line is cut. Watch what happens to each person's work.
The router sends each session to the best line, so all three run over the fibre while 4G and 5G sit idle. When the fibre fails, every session on it breaks: the call ends, the upload fails and the app loses unsaved changes. A few seconds later the router fails over and everyone starts again on 4G and 5G.
Everyone's traffic is spread across all three lines at once. When the fibre fails, the 4G and 5G lines are already carrying the call, so it continues. Nobody has to reconnect.