IP Addressing Fundamentals

CIDR: An Historic Review

CIDR was defined in RFCs 1517 through 1520, published in September 1993. As you peruse these documents, you can't help but notice the sense of urgency with which the IETF was grasping for a solution to its impending address crisis. The Internet's commercialization wrought a dramatic and rapid evolution in its size, scope, and user base. Once just populated with a few academic and research bodies collaborating on DARPA, the Internet quickly grew to global proportions. Its user community also spanned the gamut, including an ever-increasing number of users who tried desperately to figure out how to make money off the Net. The effect was rapidly increasing pressure on all the Internet's internal support mechanisms, including ...