BC8020

BC8020 is used in backbone routers. Backbones routers are needed to link 2 or more regions together. See this page for more information. If you have only 1 region, you should not use BC8020 sign.

BC8020 sign usage is exactly the same as BC8010, except that the 2nd line contains [BC8020] and the 4th line will not hold anything and can remain empty.