(1) See also
BPG.
(2) (
Border
Gateway
Protocol) The routing protocol of the Internet. Developed by the Internet Engineering Task Force (IETF), BGP is a scalable protocol that is used to span the independent "autonomous" networks that make up the Internet. See
autonomous system.
No Guarantees
BGP was designed to create a loop-free path through independently operated networks that have their own policies and objectives. As such, the route does not guarantee the shortest path, lowest cost or greatest bandwidth from the beginning to end of the transmission.
Too Fragile Perhaps
Often criticized as being vulnerable, BGP updates have been the cause of many Internet outages over the years. For example, BGP was blamed for the Facebook, Messenger, Instagram, WhatsApp outage in October 2021 that left hundreds of millions without communications for six hours.
Old and New Addressing
BGP is a path vector protocol that superseded EGP. BGP supports CIDR addressing, which increased the number of available IPv4 addresses, and Multiprotocol BGP supports IPv4 and the subsequent IPv6 addressing schemes (see
CIDR and
IPv6). See
EGP and
routing protocol.