Inventor: Jon Postel
Invention: Simple Mail Transfer Protocol (1982), File Transfer Protocol (1985) and User Datagram Protocol (1980)
The story: Protocol guru Postel, who died in 1998 at the age of 55, is known for his work in the early Internet. He invented the SMTP, a de facto standard for sending mail across the Internet; FTP, which like SMTP, is a protocol for exchanging information -- in this case, files -- over the Internet; and the UDP, which is part of TCP/IP and lets computers send short messages to each other. Ira Magaziner, who served as former President Bill Clinton's Internet policy advisor, recalled in a University of Southern California publication that the wooly bearded, often eccentrically attired Postel was once detained by Secret Service agents for 20 minutes prior to a meeting at the White House before they realized he really did have business there.
Inventor: Radia Perlman
Invention: Spanning-tree algorithm -- 1983
The story: The spanning-tree algorithm, used by all bridges and switches to route traffic from one point to another, is credited to Perlman, then working at Digital Equipment. Now sometimes called the Mother of the Internet, Perlman is a distinguished engineer at Sun, where her goal is killing off the technology she invented. The algorithm is too fragile, she says -- if a temporary loop was created, it could cause problems from which the network might never recover. "It's time to redo it in a way that is more robust and gives more efficient paths," Perlman says in her bio on Sun's site.
A poem written by Perlman describes the Spanning Tree Algorithm:
I think that I shall never seeA graph more lowly than a treeA tree whose crucial propertyIs loop-free connectivity. A tree which must be sure to spanSo packets can reach every LAN.
First the Root must be selectedBy ID it is elected.Least cost paths from Root are traced.In the tree these paths are placedA mesh is made by folks like meThen bridges find a spanning tree.
Inventors: Marshall Rose, Jeff Case, Keith McCloghrie and Steve Waldbusser
Invention: The Simple Network Management Protocol -- 1987
The story: Rose, Case, McCloghrie and Waldbusser cooked up SNMP as a way to manage distributed devices on a network. SNMP is simple in design -- it has only five commands for managing information: Get_Request, Get_Next_Request, Set_Request, Get_Response and Trap. It's no surprise so many vendors adopted it for their devices.
Inventor: Charles Hedrick
Invention: Routing Information Protocol - 1988
The story: Hedrick is responsible for RIP, a protocol that lets routers determine which networks they can communicate with and how far away those networks are. ARPANET used RIP as its initial routing algorithm.