IP Addresses

• When IP was standardized in 1981, it was intended that

• • Each host would get one unique IP address
  • Routers would get one unique IP address per interface
  • There wouldn’t be hundreds of millions of computing devices attached to the Internet

• Today, things are different

• • Most hosts are dynamically allocated addresses with DHCP or IPCP
  • Many hosts share a unique address
  • • Requires use of a network address translator (NAT)
  • There are hundreds of millions of computing devices attached to the Internet