About Dr. Roberts

Dr. Lawrence Roberts

Dr. Lawrence Roberts led the team that designed and developed ARPANET, the world's first major computer packet network. While at MIT in 1965 he created the first computer-to-computer network using a packet link between MIT and SDC. Based on that success, he moved to ARPA in 1966 as ARPA's chief scientist, and began to architect ARPANET in 1967 including the theoretical packet switching work by Leonard Kleinrock to expand the network to many nodes. Dr. Roberts designed and managed the building of the APRANET over the next 6 years. The first four computers were connected in 1969 and by 1973, 23 computers were connected worldwide. At that point Dr, Roberts turned the development over to Bob Kahn and Vint Cerf and left ARPA to form the first commercial packet network, Telenet. Today, Roberts and Kleinrock, along with Vinton Cerf and Robert Kahn, are widely recognized as the four founding fathers of the Internet.

Packet switching proved very controversial to communications people. Conventional opinion then held that packet switching could never work. Many of the University computer research centers also felt the network would steal their computer power. However, Roberts' team, in conjunction with contractor BBN, which assembled and installed the hardware, proved them both wrong and the network worked with much higher efficiency and utility than either group imagined. In 1971, in order to expand the utility of the network, Dr. Roberts wrote the first email application software, RD, to support listing, saving, forwarding and responding to email. This also became an instant success.

After ARPA, Dr. Roberts founded the world's first packet data communications carrier, Telenet - the company that developed and drove adoption of the popular X.25 data protocol. Roberts was CEO from 1973 to 1980. Telenet was sold to GTE in 1979 and subsequently became the data division of Sprint. From 1983 to 1993, Roberts was Chairman and CEO of NetExpress, an electronics company specializing in packetized fax and ATM equipment.

From 1993 to 1998 Dr. Roberts was President of ATM Systems, where he designed advanced ATM and Ethernet switches with QoS and Explicit Rate flow control. He proposed Explicit Rate to the ATM Forum in 1994 and spearheaded its development into ATM Forum recommendation TM 4.0 in 1996. He has also led the development of a protocol for ATM over Ethernet called Cells In Frames

In 1999 Dr. Roberts undertook to redesign the IP router (not the protocol) to route flows, not just random packets, to support high Quality of Service. (QoS) flows across the IP network. To do this he founded Caspian Networks which built highly capable flow routers that accomplished the goal of ATM quality QoS compatibly over IP networks. These routers were aimed at the network core and started deployment in 2003 for QoS sensitive applications like video conferencing and P2P traffic control. However, this first generation of flow routers was large, expensive, and did not take advantage of many simplifications that were possible. Thus, Dr. Roberts left Caspian in 2004 in  order to create a more efficient and economic flow management system.

In 2004 Dr. Roberts founded Anagran Inc. Realizing that the output queue design of packet switches and routers was causing major delay, packet loss, and unfairness, and   he designed a new concept of flow management where each flow is precisely rate controlled at the input rather than randomly at the output. The flow manager concept only required 20% of the power and size of a L3 router, virtually eliminated queuing delay and packet loss for both file transfers and streaming media, optimized network utilization, and greatly  improved fairness. Thus, instead of the prevailing concept that Quality of Service (QoS) would increase the complexity and cost of a network, the QoS could be greatly improved with less complexity while at the same time reducing network cost by eliminating the need for overcapacity. 

Dr. Roberts has B.S., M.S., and PhD. degrees from MIT. Today he lives in Silicon Valley.

Dr. Roberts has received a number of awards for his work in computer networking:


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