Complex sentence: Border Gateway Protocol (BGP) is the protocol which is used to make core routing decisions on the Internet; it involves a table of IP networks or "prefixes" which designate network reach-ability among autonomous systems (AS).
Split into simpler sentences: Border Gateway Protocol (BGP) is the protocol which is used to make core routing decisions on the Internet. It maintains a table of IP networks or "prefixes" which designate network reach-ability among autonomous systems (AS).