Informatics Distinguished Lecture - 27/04/2026 @ 4pm Title: Networking Lessons learned: From Congestion Avoidance to building Software-Based NetworksAbstract: Having worked in networked systems for a while, I will look back at some of the lessons we have learned.Networked applications are ubiquitous and their performance requirements are increasingly stringent. Network congestion can seriously impact performance contributing to increased latency, packet loss and poor throughput. To address these problems, the networking community has come up with a large number of congestion control algorithms over the years. These can be classified into two broad classes: one based on an end-system's perception of network congestion and the other based on the network providing feedback to flows that pass through it. At the same time, the focus for congestion control has expanded from just being in the wide-area and metro networks to data centers and wireless networks including cellular environments. In the first part of the talk, I will discuss the different kinds of feedback-based congestion control, with the signal for congestion ranging from just using end-system based inference of congestion to signals generated from within the network. I will describe our work on seeking to understand the benefits of network-generated feedbackCommunication networks are also changing. They are becoming more and more “software-based”, especially with the use of Network Function Virtualization (NFV) to run network services in software, in the cloud. I will talk about our NFV platform, OpenNetVM, and our work on developing a high performance, low-latency core for 5G cellular networks. Our core, L25GC+, re-architects the 5G core (5GC) network, and its processing, to reduce latency of control plane operations and their impact on the data plane. Exploiting shared memory, L25GC+ eliminates message serialization and HTTP processing overheads, while being 3GPP-standards compliant. L25GC+ reduces event completion time by ~50% for several control plane events and improves data packet latency (due to improved control plane communication) by ~2×, during paging and handover events. But we realize that truly achieving high-performance requires us to also re-think the protocols we use in cellular networks, not just implement the same set of protocols on a competent system. Holistic solutions that exploit the use of flexible software platforms and adapt network protocols to eliminate unnecessary message exchanges can truly offer significant benefits.Bio: Dr. K. K. Ramakrishnan is a Distinguished Professor of Computer Science and Engineering at the University of California, Riverside. He joined AT&T Bell Labs in 1994 and was with AT&T Labs-Research from its inception in 1996, until 2013, as a Distinguished Member of Technical Staff. Before 1994, he was a Technical Director and Consulting Engineer in Networking at Digital Equipment Corporation. Between 2000 and 2002, he was at TeraOptic Networks, Inc., as Founder and Vice President.Dr. Ramakrishnan is an ACM Fellow, an IEEE Fellow, and an AT&T Fellow, recognized for his fundamental contributions to communication networks, including his work on congestion control, traffic management, and VPN services. His work on the "DECbit" congestion avoidance protocol received the ACM Sigcomm Test of Time Paper Award in 2006, and he received the AT&T Technology Medal in 2012 for his work on Mobile Video Delivery. He received the 2024 ACM SIGCOMM Award recognizing his lifetime contribution to the field of communication networks. He has published over 300 papers and has 186 patents issued in his name. K.K. has been on the editorial board of several journals and has served as the TPC Chair and General Chair for several networking conferences. K. K. received his MTech from the Indian Institute of Science (1978, recently recognized as one of IISc’s Distinguished Alumni), MS (1981) and Ph.D. (1983) in Computer Science from the University of Maryland, College Park, USA. Apr 27 2026 16.00 - 17.00 Informatics Distinguished Lecture - 27/04/2026 @ 4pm Dr. K. K. Ramakrishnan (Distinguished Professor of Computer Science and Engineering at University of California, Riverside) G.07, IF
Informatics Distinguished Lecture - 27/04/2026 @ 4pm Title: Networking Lessons learned: From Congestion Avoidance to building Software-Based NetworksAbstract: Having worked in networked systems for a while, I will look back at some of the lessons we have learned.Networked applications are ubiquitous and their performance requirements are increasingly stringent. Network congestion can seriously impact performance contributing to increased latency, packet loss and poor throughput. To address these problems, the networking community has come up with a large number of congestion control algorithms over the years. These can be classified into two broad classes: one based on an end-system's perception of network congestion and the other based on the network providing feedback to flows that pass through it. At the same time, the focus for congestion control has expanded from just being in the wide-area and metro networks to data centers and wireless networks including cellular environments. In the first part of the talk, I will discuss the different kinds of feedback-based congestion control, with the signal for congestion ranging from just using end-system based inference of congestion to signals generated from within the network. I will describe our work on seeking to understand the benefits of network-generated feedbackCommunication networks are also changing. They are becoming more and more “software-based”, especially with the use of Network Function Virtualization (NFV) to run network services in software, in the cloud. I will talk about our NFV platform, OpenNetVM, and our work on developing a high performance, low-latency core for 5G cellular networks. Our core, L25GC+, re-architects the 5G core (5GC) network, and its processing, to reduce latency of control plane operations and their impact on the data plane. Exploiting shared memory, L25GC+ eliminates message serialization and HTTP processing overheads, while being 3GPP-standards compliant. L25GC+ reduces event completion time by ~50% for several control plane events and improves data packet latency (due to improved control plane communication) by ~2×, during paging and handover events. But we realize that truly achieving high-performance requires us to also re-think the protocols we use in cellular networks, not just implement the same set of protocols on a competent system. Holistic solutions that exploit the use of flexible software platforms and adapt network protocols to eliminate unnecessary message exchanges can truly offer significant benefits.Bio: Dr. K. K. Ramakrishnan is a Distinguished Professor of Computer Science and Engineering at the University of California, Riverside. He joined AT&T Bell Labs in 1994 and was with AT&T Labs-Research from its inception in 1996, until 2013, as a Distinguished Member of Technical Staff. Before 1994, he was a Technical Director and Consulting Engineer in Networking at Digital Equipment Corporation. Between 2000 and 2002, he was at TeraOptic Networks, Inc., as Founder and Vice President.Dr. Ramakrishnan is an ACM Fellow, an IEEE Fellow, and an AT&T Fellow, recognized for his fundamental contributions to communication networks, including his work on congestion control, traffic management, and VPN services. His work on the "DECbit" congestion avoidance protocol received the ACM Sigcomm Test of Time Paper Award in 2006, and he received the AT&T Technology Medal in 2012 for his work on Mobile Video Delivery. He received the 2024 ACM SIGCOMM Award recognizing his lifetime contribution to the field of communication networks. He has published over 300 papers and has 186 patents issued in his name. K.K. has been on the editorial board of several journals and has served as the TPC Chair and General Chair for several networking conferences. K. K. received his MTech from the Indian Institute of Science (1978, recently recognized as one of IISc’s Distinguished Alumni), MS (1981) and Ph.D. (1983) in Computer Science from the University of Maryland, College Park, USA. Apr 27 2026 16.00 - 17.00 Informatics Distinguished Lecture - 27/04/2026 @ 4pm Dr. K. K. Ramakrishnan (Distinguished Professor of Computer Science and Engineering at University of California, Riverside) G.07, IF
Apr 27 2026 16.00 - 17.00 Informatics Distinguished Lecture - 27/04/2026 @ 4pm Dr. K. K. Ramakrishnan (Distinguished Professor of Computer Science and Engineering at University of California, Riverside)
