Techniques for improving predictability and message efficiency of gossip protocols

Ph.DDOCTOR OF PHILOSOPH

Agent organization in the KP

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (p. 181-191).In designing and building a network like the Internet, we continue to face the problems of scale and distribution. With the dramatic expansion in scale and heterogeneity of the Internet, network management has become an increasingly difficult task. Furthermore, network applications often need to maintain efficient organization among the participants by collecting information from the underlying networks. Such individual information collection activities lead to duplicate efforts and contention for network resources. The Knowledge Plane (KP) is a new common construct that provides knowledge and expertise to meet the functional, policy and scaling requirements of network management, as well as to create synergy and exploit commonality among many network applications. To achieve these goals, we face many challenging problems, including widely distributed data collection, efficient processing of that data, wide availability of the expertise, etc. In this thesis, to provide better support for network management and large-scale network applications, I propose a knowledge plane architecture that consists of a network knowledge plane (NetKP) at the network layer, and on top of it, multiple specialized KPs (spec-KPs). The NetKP organizes agents to provide valuable knowledge and facilities about the Internet to the spec-KPs. Each spec-KP is specialized in its own area of interest. In both the NetKP and the spec-KPs, agents are organized into regions based on different sets of constraints. I focus on two key design issues in the NetKP: (1) a region-based architecture for agent organization, in which I design an efficient and non-intrusive organization among regions that combines network topology and a distributed hash table; (2) request and knowledge dissemination, in which I design a robust and efficient broadcast and aggregation mechanism using a tree structure among regions.(cont.) In the spec-KPs, I build two examples: experiment management on the PlanetLab testbed and distributed intrusion detection on the DETER testbed. The experiment results suggest a common approach driven by the design principles of the Internet and more specialized constraints can derive productive organization for network management and applications.by Ji Li.Ph.D

Agent Organization in the Knowledge Plane

In designing and building a network like the Internet, we continue to face the problems of scale and distribution. With the dramatic expansion in scale and heterogeneity of the Internet, network management has become an increasingly difficult task. Furthermore, network applications often need to maintain efficient organization among the participants by collecting information from the underlying networks. Such individual information collection activities lead to duplicate efforts and contention for network resources.The Knowledge Plane (KP) is a new common construct that provides knowledge and expertise to meet the functional, policy and scaling requirements of network management, as well as to create synergy and exploit commonality among many network applications. To achieve these goals, we face many challenging problems, including widely distributed data collection, efficient processing of that data, wide availability of the expertise, etc.In this thesis, to provide better support for network management and large-scale network applications, I propose a knowledge plane architecture that consists of a network knowledge plane (NetKP) at the network layer, and on top of it, multiple specialized KPs (spec-KPs). The NetKP organizes agents to provide valuable knowledge and facilities about the Internet to the spec-KPs. Each spec-KP is specialized in its own area of interest. In both the NetKP and the spec-KPs, agents are organized into regions based on different sets of constraints. I focus on two key design issues in the NetKP: (1) a regionbased architecture for agent organization, in which I design an efficient and non-intrusive organization among regions that combines network topology and a distributed hash table; (2) request and knowledge dissemination, in which I design a robust and efficient broadcast and aggregation mechanism using a tree structure among regions. In the spec-KPs, I build two examples: experiment management on the PlanetLab testbed and distributed intrusion detection on the DETER testbed. The experiment results suggest a common approach driven by the design principles of the Internet and more specialized constraints can derive productive organization for network management and applications

A Distributed Inter-Domain Control System for Information-Centric Content Delivery

The Internet, the de facto platform for large-scale content distribution, suffers from two issues that limit its manageability, efficiency and evolution: (1) The IP-based Internet is host-centric and agnostic to the content being delivered and (2) the tight coupling of the control and data planes restrict its manageability, and subsequently the possibility to create dynamic alternative paths for efficient content delivery. Here we present the CURLING system that leverages the emerging Information-Centric Networking paradigm for enabling cost-efficient Internet-scale content delivery by exploiting multicasting and in-network caching. Following the software-defined networking concept that decouples the control and data planes, CURLING adopts an inter-domain hop-by-hop content resolution mechanism that allows network operators to dynamically enforce/change their network policies in locating content sources and optimizing content delivery paths. Content publishers and consumers may also control content access according to their preferences. Based on both analytical modelling and simulations using real domain-level Internet sub-topologies, we demonstrate how CURLING supports efficient Internet-scale content delivery without the necessity for radical changes to the current Internet

Effective bootstrapping of Peer-to Peer networks over Mobile Ad-hoc networks

Mobile Ad-hoc Networks (MANETs) and Peer-to-Peer (P2P) networks are vigorous, revolutionary communication technologies in the 21st century. They lead the trend of decentralization. Decentralization will ultimately win clients over client/server model, because it gives ordinary network users more control, and stimulates their active participation. It is a determinant factor in shaping the future of networking. MANETs and P2P networks are very similar in nature. Both are dynamic, distributed. Both use multi-hop broadcast or multicast as major pattern of traffic. Both set up connection by self-organizing and maintain connection by self-healing. Embodying the slogan networking without networks, both abandoned traditional client/server model and disclaimed pre-existing infrastructure. However, their status quo levels of real world application are widely divergent. P2P networks are now accountable for about 50 ~ 70% internet traffic, while MANETs are still primarily in the laboratory. The interesting and confusing phenomenon has sparked considerable research effort to transplant successful approaches from P2P networks into MANETs. While most research in the synergy of P2P networks and MANETs focuses on routing, the network bootstrapping problem remains indispensable for any such transplantation to be realized. The most pivotal problems in bootstrapping are: (1) automatic configuration of nodes addresses and IDs, (2) topology discovery and transformation in different layers and name spaces. In this dissertation research, we have found novel solutions for these problems. The contributions of this dissertation are: (1) a non-IP, flat address automatic configuration scheme, which integrates lower layer addresses and P2P IDs in application layer and makes simple cryptographical assignment possible. A related paper entitled Pastry over Ad-Hoc Networks with Automatic Flat Address Configuration was submitted to Elsevier Journal of Ad Hoc Networks in May. (2) an effective ring topology construction algorithm which builds perfect ring in P2P ID space using only simplest multi-hop unicast or multicast. Upon this ring, popular structured P2P networks like Chord, Pastry could be built with great ease. A related paper entitled Chord Bootstrapping on MANETs - All Roads lead to Rome will be ready for submission after defense of the dissertation

AS-cast: Lock Down the Traffic of Decentralized Content Indexing at the Edge

International audienceAlthough the holy grail to store and manipulate data in Edge infrastructures is yet to be found, state-of-the-art approaches demonstrated the relevance of replication strategies that bring content closer to consumers: The latter enjoy better response time while the volume of data passing through the network decreases overall. Unfortunately, locating the closest replica of a specific content requires indexing every live replica along with its location. Relying on remote services for such a aim enters in contradiction with the properties of Edge infrastructures as locating replicas may effectively take more time than actually downloading content. At the opposite, maintaining such an index at every node would prove overly costly in terms of memory and traffic. In this paper, we propose a decentralized implementation of content indexing called AS-cast. Using AS-cast, every node only indexes its closest replica; and all connected nodes with a similar index compose a partition. AS-cast is (i) efficient, for it uses partitions to lock down the traffic generated by its operations to relevant nodes, yet it (ii) guarantees that every node eventually acknowledges its closest replica despite concurrent operations. Our prototype, implemented on PeerSim, shows that AS-cast scales well in terms of generated messages and termination time. As such, AS-cast can constitute a novel building block for geo-distributed services in need of efficient resource sharing in the vicinity of regions

AS-cast: Lock Down the Traffic of Decentralized Content Indexing at the Edge

International audienceAlthough the holy grail to store and manipulate data in Edge infrastructures is yet to be found, state-of-the-art approaches demonstrated the relevance of replication strategies that bring content closer to consumers: The latter enjoy better response time while the volume of data passing through the network decreases overall. Unfortunately, locating the closest replica of a specific content requires indexing every live replica along with its location. Relying on remote services for such a aim enters in contradiction with the properties of Edge infrastructures as locating replicas may effectively take more time than actually downloading content. At the opposite, maintaining such an index at every node would prove overly costly in terms of memory and traffic. In this paper, we propose a decentralized implementation of content indexing called AS-cast. Using AS-cast, every node only indexes its closest replica; and all connected nodes with a similar index compose a partition. AS-cast is (i) efficient, for it uses partitions to lock down the traffic generated by its operations to relevant nodes, yet it (ii) guarantees that every node eventually acknowledges its closest replica despite concurrent operations. Our prototype, implemented on PeerSim, shows that AS-cast scales well in terms of generated messages and termination time. As such, AS-cast can constitute a novel building block for geo-distributed services in need of efficient resource sharing in the vicinity of regions

Rohc-Mpls Tunnel Architecture For Wireless Mesh

Natural or human-made disasters are sudden events that can cause significant damage, especially to the network communication infrastructure. In these events, a rapid deployment of network communication systems is required in order to relay or receive the communication among the people in the disaster areas to conduct relief and rescue efforts. Wireless mesh networks have emerged and has been recognised for its potential for rapid deployment and last mile coverage of network infrastructure, which is highly suitable for emergency response management. While wireless mesh networks have beneficial attributes, it also introduces some crucial problems. During data transmission, the path recovery time is significantly higher resulting in the loss of data if node and link failures occur