Quote from: pebwindkraft on February 06, 2018, 11:52:28 PM

Remember good old CISCO 27xx or 29xx models with configs for RIPv1 and v2, and then open shortest path first (OSPF)? These were the internal routing protocols. Then there was the bigger networks in the late 80s and they needed a professional base layer (border gateway protocol, BGP and IGRP/EGRP, or EGP). And of course a DNS. btw: why is DNSsec not used today?

Surely you mean the 2500 Series? (Ooops showing my age again.) This is a good demonstration of how easy it is solve scaling issues at layer 3. When the limitations of RIP became apparent it was easy to simply add additional routing protocols to solve the problems. For example, EIGRP is a Cisco proprietary protocol that can be used in areas of the network using exclusively Cisco equipment and then BGP handles connecting to other areas that may not be.

I see so many debates about the possible limitations of Lightning Network that miss this. It's not an end product set in stone, it will constantly evolve to address any issues that arise. That's not so easy to do in blockchain where much was set in stone in the genesis block.

Quote from: pebwindkraft on February 06, 2018, 11:52:28 PM

Spanning tree was the protection layer in bridges, to prevent loops in larger networks, with the "routing" of MAC addresses (bridge = layer 2 device). Yup, no routing at layer 4 here ...

Pedantic Note: STP allowed layer 2 topologies to be designed with redundancy built in by temporarily blocking loops and then opening them when a failure elsewhere eliminated the loop.