Backbone

The backbone network is a transportation network at an upper routing level. Its role is to transport cart from regions to regions. It does not contain stations and rings.

The backbone network is made of:

• backbone routers using BC8020 signs
• backbone link to link backbone routers together, that are like rings with no stations at all
• interlink ring, to attach backbone routers to regions. This special ring does not contain stations and has a backbone router at one end, and a region router at the other end.

Making a backbone network is very simple : just make routers (with BC8020 sign) close from the ring 0 of the region they must connect. Plug them into the ring 0 of the region, and link all the backbone routers together with empty rings. A single backbone router can attach up to 3 regions (4 if there is only one backbone router in your world), the 4th interface is connected to the backbone network.

Launch a backbone updater from a free interface of a backbone router : it will become the region 0. Wait until the updater completes its configuration and that's all.

You are not limited in the number of backbone routers, so you can build as many of them as you want, but there is a hard limit of 15 routers for the "diameter" of the backbone network, meaning that carts must not cross more than 15 backbone routers to go from one region to another.