Service Placement in Ad Hoc Networks

Abstract

Service provisioning in ad hoc networks is challenging given the difficulties of communicating over a wireless channel and the potential heterogeneity and mobility of the devices that form the network. In order to optimize the performance of the network over which a service host provides a service to client nodes, it is necessary to continuously adapt the logical network topology to both external (e.g., wireless connectivity, mobility, churn) and internal (e.g., communication patterns, service demand) factors. Recent proposals advocate that nodes should dynamically choose which nodes in the network are to provide application-level services to other nodes. Services in this context range from infrastructural services such as the Domain Name System (DNS) to user-oriented services such as the World Wide Web (WWW).Service placement is the process of selecting an optimal set of nodes to host the implementation of a service in light of a given service demand and network topology. The main questions addressed by service placement are: How many instances of the same service should be available in the network and cooperate to process clients' service requests; where these service instances should be placed, i.e., which nodes are best suited for hosting them;and when to adapt the current service configuration. The service instances of a distributively operating service are exact copies of the software component that provides the service, including both the executable binary and the application-level data. The set of nodes that host a service instance is referred to as the service configuration. A good service configuration increases the performance of a service according to application-specific quality metrics, while at the same time potentially reducing the overall network load. The key advantage of active service placement in ad hoc networks is that it allows for the service configuration to be adapted continuously at run time.In this work, we propose the SPi service placement framework as a novel approach to service placement in ad hoc networks. The SPi framework takes advantage of the interdependencies between service placement, service discovery and the routing of service requests to minimize signaling overhead. We also propose the Graph Cost / Single Instance (GCSI) and the Graph Cost / Multiple Instances (GCMI) placement algorithms. The SPi framework employs these algorithms to optimize the number and the location of service instances based on usage statistics and a partial network topology derived from routing information. The GCSI and GCMI placement algorithms only require minimal knowledge about the service they are tasked with placing in the network. They are novel in that they take the communication between service instances into account which is required to synchronize the global state of the service. Furthermore, when calculating the optimal timing of their placement decisions, the two algorithms explicitly consider the overhead of the actions required for implementing changes to the current service c...

Self-Organized Disjoint Service Placement in Future Mobile Communication Networks

“…Distributed service placement strategies offer more promising solutions to the service placement problem. In [19] the authors present a service placement technique for ad hoc networks called SPi. The proposed algorithm tries to find the best places for services placement taking into consideration the multi-hop scenario of ad hoc networks.…”

Enhancing Routing for Wireless Ad-Hoc Networks to Improve Quality of Service in Mobile Learning

“…On the other hand, [21] discusses the problem of service placement. In order to facilitate communication within the network, and guarantee service placement among other things, the main objective is to determine correct routes, enabling timely communication among them, and doing the latter in an efficient manner: path construction should consume as little overhead and bandwidth as possible.…”

On the service placement in community network micro-clouds

“…The question of identifying the appropriate nodes in the CN micro-clouds to act as servers is referred to as the service placement problem, whose goal is to establish an optimal or near-optimal service configuration, i.e., selection of nodes to host the instances of the service which is optimal in regard to some service-specific metric [Wit10].…”

“…The authors in [Wit10] propose a service placement framework as a novel approach to service placement in wireless ad hoc network. Their 𝑆𝑃 𝑖 framework takes advantage of the inter-dependencies between service placement, service discovery and the routing of service requests to minimize signaling overhead.…”