Border Gateway Protocol (BGP)
The Border Gateway Protocol (BGP) is used in the internet as routing protocol. It connects autonomous systems (AS) which are generally formed by internet providers. The BGP is generally known as Exterior Gateway Protocol (EGP) and path vector protocol. The routing decisions are based on both strategic and technical criteria. In practise, however, economic reasons are crucial. Within autonomous systems, Interior Gateway Protocols (IGPs) are used.