acm sigcomm

Centralizing routing decisions offers tremendous flexibility, but sacrifices the robustness of distributed protocols. In this paper, we present Fibbing, an architecture that achieves both flexibility and robustness through central control over distributed routing. Fibbing introduces fake nodes and links into an underlying linkstate routing protocol, so that routers compute their own forwarding tables based on the augmented topology. Fibbing is expressive, and readily supports flexible load balancing, traffic engineering, and backup routes.

BGP severely constrains how networks can deliver traffic over the Internet. Today’s networks can only forward traffic based on the destination IP prefix, by selecting among routes offered by their immediate neighbors. We believe Software Defined Networking (SDN) could revolutionize wide-area traffic delivery, by offering direct control over packet-processing rules that match on multiple header fields and perform a variety of actions.

We present Dionysus, a system for fast, consistent network updates in software-defined networks. Dionysus encodes as a graph the consistency-related dependencies among updates at individual switches, and it then dynamically schedules these updates based on runtime differences in the update speeds of different switches. This dynamic scheduling is the key to its speed; prior update methods are slow because they pre-determine a schedule, which does not adapt to runtime conditions.

BGP severely constrains how networks can deliver traffic over the Internet. Today’s networks can only forward traffic based on the destination IP prefix, by selecting among routes offered by their immediate neighbors. We believe Software Defined Networking (SDN) could revolutionize wide-area traffic delivery, by offering direct control over packet-processing rules that match on multiple header fields and perform a variety of actions.

We present Statesman, a network-state management service that allows multiple network management applications to operate independently, while maintaining network-wide safety and performance invariants. Network state captures various aspects of the network such as which links are alive and how switches are forwarding traffic. Statesman uses three views of the network state. In observed state, it maintains an up-to-date view of the actual network state. Applications read this state and propose state changes based on their individual goals.

A workshop on Abstractions for Network Services, Architecture, and Implementation brought together researchers interested in creating better abstractions for creating and analyzing networked services and network architectures. The workshop took place at DIMACS on May 21-23, 2012. This report summarizes the presentations and discussions that took place at the workshop, organized by areas of abstractions such as layers, domains, and graph properties.

Traditional traffic engineering adapts the routing of traffic within the network to maximize performance. We propose a new approach that also adaptively changes where traffic enters and leaves the network—changing the “traffic matrix”, and not just the intradomain routing configuration. Our approach does not affect traffic patterns and BGP routes seen in neighboring networks, unlike conventional inter-domain traffic engineering where changes in BGP policies shift traf-

While computer networking is an exciting research field, we are far from having a clear understanding of the core concepts and questions that define our discipline. This position paper, a summary of a talk I gave at the CoNext’10 Student Workshop, captures my current frustrations and hopes about the field.

We argue that the biggest problem with the current Internet architecture is not a particular functional deficiency, but its inability to accommodate innovation. To address this problem we propose a minimal architectural “framework” in which comprehensive architectures can reside. The proposed Framework for Internet Innovation (FII) — which is derived from the simple observation that network interfaces should be extensible and abstract — allows for a diversity of architectures to coexist, communicate, and evolve.

In response to high-profile Internet outages, BGP security variants have been proposed to prevent the propagation of bogus routing information. To inform discussions of which variant should be deployed in the Internet, we quantify the ability of the main protocols (origin authentication, soBGP, S-BGP, and data-plane verification) to blunt traffic-attraction attacks; i.e., an attacker that deliberately attracts traffic to drop, tamper, or eavesdrop on packets.