2019 28th International Conference on Computer Communication and Networks (ICCCN), 2019
We present a control module for software edge routers called Receive Window Modulation-RWM. Its m... more We present a control module for software edge routers called Receive Window Modulation-RWM. Its main objective is to mitigate what we define as self-induced congestion: the result of traffic emission patterns at the source that cause buffering and packet losses in any of the intermediate routers along the path between the connection's endpoints. The controller modifies the receiver's TCP advertised window to match the computed bandwidth-delay product, based on the connection round-trip time estimation and the bandwidth locally available at the edge router. The implemented controller does not need any endpoint modification, allowing it to be deployed in corporate edge routers, increasing visibility and control capabilities. This scheme, when used in real-world experiments with loss-based congestion control algorithms such as CUBIC, is shown to optimize access link utilization and per-connection goodput, and to reduce latency variability and packet losses.
Fog Computing extends the Cloud Computing paradigm to the edge of the network, thus enabling a ne... more Fog Computing extends the Cloud Computing paradigm to the edge of the network, thus enabling a new breed of applications and services. Defining characteristics of the Fog are: a) Low latency and location awareness; b) Wide-spread geographical distribution; c) Mobility; d) Very large number of nodes, e) Predominant role of wireless access, f) Strong presence of streaming and real time applications, g) Heterogeneity. In this paper we argue that the above characteristics make the Fog the appropriate platform for a number of critical Internet of Things (IoT) services and applications,
Fog Computing in the Internet of Things, May 31, 2017
The Internet of Things (IoT) marks a phase transition in the evolution of the Internet, distingui... more The Internet of Things (IoT) marks a phase transition in the evolution of the Internet, distinguished by a massive connectivity and the interaction with the physical world. The organic evolution of IoT requires the consideration of three dimensions: scale, organization, and context. These dimensions are particularly relevant in Ultra Large Scale Systems (ULSS), of which Autonomous Vehicles is a prime example. Fog Computing is well positioned to support contextual awareness and communication, critical for ULSS. The design and orchestration of ULSS require fresh approaches, new organizing principles. A recent paper proposed HEB (Hierarchical Emergent Behaviors), an architecture that builds on established concepts of emergent behaviors and hierarchical decomposition and organization. HEB's local rules induce emergent behaviors, i.e., useful behaviors not explicitly programmed. In this chapter we take a first step to validate HEB concepts through the study of two basic self-driven car "primitives": exiting a platoon formation, and maneuvering in anticipation of obstacles beyond the range of on-board sensors. Fog nodes provide the critical contextual information required.
With the rapid growth in renewable energy and battery storage technologies, there exists signific... more With the rapid growth in renewable energy and battery storage technologies, there exists significant opportunity to improve energy efficiency and reduce costs through optimization. However, optimization algorithms must take into account the underlying dynamics and uncertainties of the various interconnected subsystems in order to fully realize this potential. To this end, we formulate and solve an energy management optimization problem as a Markov Decision Process (MDP) consisting of battery storage dynamics, a stochastic demand model, a stochastic solar generation model, and an electricity pricing scheme. The stochastic model for predicting solar generation is constructed based on weather forecast data from the National Oceanic and Atmospheric Administration. A near-optimal policy design is proposed via stochastic dynamic programming.
Widespread deployment of autonomous vehicles (AVs) presents formidable challenges in terms on han... more Widespread deployment of autonomous vehicles (AVs) presents formidable challenges in terms on handling scalability and complexity, particularly regarding vehicular reaction in the face of unforeseen corner cases. Hierarchical Emergent Behaviors (HEB) is a scalable architecture based on the concepts of emergent behaviors and hierarchical decomposition. It relies on a few simple but powerful rules to govern local vehicular interactions. Rather than requiring prescriptive programming of every possible scenario, HEB's approach relies on global behaviors induced by the application of these local, well-understood rules. Our first two papers on HEB focused on a primal set of rules applied at the first hierarchical level. On the path to systematize a solid design methodology, this paper proposes additional rules for the second level, studies through simulations the resultant richer set of emergent behaviors, and discusses the communication mechanisms between the different levels.
2011 IEEE 19th Annual International Symposium on Modelling, Analysis, and Simulation of Computer and Telecommunication Systems, 2011
As the evolution of multi-core multi-threaded processors continues, the complexity demanded to pe... more As the evolution of multi-core multi-threaded processors continues, the complexity demanded to perform an extensive trade-off analysis, increases proportionally. Cycleaccurate or trace-driven simulators are too slow to execute the large amount of experiments required to obtain indicative results. To achieve a thorough analysis of the system, software benchmarks or traces are required. In many cases when an analysis is needed most, during the earlier stages of the processor design, benchmarks or traces are not available. Analytical models overcome these limitations but do not provide the fine grain details needed for a deep analysis of these architectures.
This paper introduces a new packet processor designed for stateful networking applications: those... more This paper introduces a new packet processor designed for stateful networking applications: those applications where there is a requirement to support a large amount of state with little locality of access. Stateful applications require a high rate of external memory accesses, and this in turn implies a high degree of parallelism is needed. Our packet processor utilizes multiple multithreaded processing engines to support this parallelism in a design that supports 256 simultaneous threads in eight processing engines. Each thread has its own independent register file and executes instructions formatted to a general purpose ISA, while sharing execution resources and memory ports with other threads. The processor is optimized to sacrifice single threaded performance, so that a design is achieved that is realizable in terms of silicon area and clock frequency. The use of a general purpose ISA and other features achieves a design in which software porting issues are minimized.
2019 28th International Conference on Computer Communication and Networks (ICCCN), 2019
We present a control module for software edge routers called Receive Window Modulation-RWM. Its m... more We present a control module for software edge routers called Receive Window Modulation-RWM. Its main objective is to mitigate what we define as self-induced congestion: the result of traffic emission patterns at the source that cause buffering and packet losses in any of the intermediate routers along the path between the connection's endpoints. The controller modifies the receiver's TCP advertised window to match the computed bandwidth-delay product, based on the connection round-trip time estimation and the bandwidth locally available at the edge router. The implemented controller does not need any endpoint modification, allowing it to be deployed in corporate edge routers, increasing visibility and control capabilities. This scheme, when used in real-world experiments with loss-based congestion control algorithms such as CUBIC, is shown to optimize access link utilization and per-connection goodput, and to reduce latency variability and packet losses.
Fog Computing extends the Cloud Computing paradigm to the edge of the network, thus enabling a ne... more Fog Computing extends the Cloud Computing paradigm to the edge of the network, thus enabling a new breed of applications and services. Defining characteristics of the Fog are: a) Low latency and location awareness; b) Wide-spread geographical distribution; c) Mobility; d) Very large number of nodes, e) Predominant role of wireless access, f) Strong presence of streaming and real time applications, g) Heterogeneity. In this paper we argue that the above characteristics make the Fog the appropriate platform for a number of critical Internet of Things (IoT) services and applications,
Fog Computing in the Internet of Things, May 31, 2017
The Internet of Things (IoT) marks a phase transition in the evolution of the Internet, distingui... more The Internet of Things (IoT) marks a phase transition in the evolution of the Internet, distinguished by a massive connectivity and the interaction with the physical world. The organic evolution of IoT requires the consideration of three dimensions: scale, organization, and context. These dimensions are particularly relevant in Ultra Large Scale Systems (ULSS), of which Autonomous Vehicles is a prime example. Fog Computing is well positioned to support contextual awareness and communication, critical for ULSS. The design and orchestration of ULSS require fresh approaches, new organizing principles. A recent paper proposed HEB (Hierarchical Emergent Behaviors), an architecture that builds on established concepts of emergent behaviors and hierarchical decomposition and organization. HEB's local rules induce emergent behaviors, i.e., useful behaviors not explicitly programmed. In this chapter we take a first step to validate HEB concepts through the study of two basic self-driven car "primitives": exiting a platoon formation, and maneuvering in anticipation of obstacles beyond the range of on-board sensors. Fog nodes provide the critical contextual information required.
With the rapid growth in renewable energy and battery storage technologies, there exists signific... more With the rapid growth in renewable energy and battery storage technologies, there exists significant opportunity to improve energy efficiency and reduce costs through optimization. However, optimization algorithms must take into account the underlying dynamics and uncertainties of the various interconnected subsystems in order to fully realize this potential. To this end, we formulate and solve an energy management optimization problem as a Markov Decision Process (MDP) consisting of battery storage dynamics, a stochastic demand model, a stochastic solar generation model, and an electricity pricing scheme. The stochastic model for predicting solar generation is constructed based on weather forecast data from the National Oceanic and Atmospheric Administration. A near-optimal policy design is proposed via stochastic dynamic programming.
Widespread deployment of autonomous vehicles (AVs) presents formidable challenges in terms on han... more Widespread deployment of autonomous vehicles (AVs) presents formidable challenges in terms on handling scalability and complexity, particularly regarding vehicular reaction in the face of unforeseen corner cases. Hierarchical Emergent Behaviors (HEB) is a scalable architecture based on the concepts of emergent behaviors and hierarchical decomposition. It relies on a few simple but powerful rules to govern local vehicular interactions. Rather than requiring prescriptive programming of every possible scenario, HEB's approach relies on global behaviors induced by the application of these local, well-understood rules. Our first two papers on HEB focused on a primal set of rules applied at the first hierarchical level. On the path to systematize a solid design methodology, this paper proposes additional rules for the second level, studies through simulations the resultant richer set of emergent behaviors, and discusses the communication mechanisms between the different levels.
2011 IEEE 19th Annual International Symposium on Modelling, Analysis, and Simulation of Computer and Telecommunication Systems, 2011
As the evolution of multi-core multi-threaded processors continues, the complexity demanded to pe... more As the evolution of multi-core multi-threaded processors continues, the complexity demanded to perform an extensive trade-off analysis, increases proportionally. Cycleaccurate or trace-driven simulators are too slow to execute the large amount of experiments required to obtain indicative results. To achieve a thorough analysis of the system, software benchmarks or traces are required. In many cases when an analysis is needed most, during the earlier stages of the processor design, benchmarks or traces are not available. Analytical models overcome these limitations but do not provide the fine grain details needed for a deep analysis of these architectures.
This paper introduces a new packet processor designed for stateful networking applications: those... more This paper introduces a new packet processor designed for stateful networking applications: those applications where there is a requirement to support a large amount of state with little locality of access. Stateful applications require a high rate of external memory accesses, and this in turn implies a high degree of parallelism is needed. Our packet processor utilizes multiple multithreaded processing engines to support this parallelism in a design that supports 256 simultaneous threads in eight processing engines. Each thread has its own independent register file and executes instructions formatted to a general purpose ISA, while sharing execution resources and memory ports with other threads. The processor is optimized to sacrifice single threaded performance, so that a design is achieved that is realizable in terms of silicon area and clock frequency. The use of a general purpose ISA and other features achieves a design in which software porting issues are minimized.
Uploads
Papers by Rodolfo Milito