NETWORK AND DOMAIN AUTOCONFIGURATION: A UNIFIED FRAMEWORK FOR LARGE MOBILE AD HOC NETWORKS

Abstract

Configuration management is critical to correct and efficient operation of large networks. In those cases where the users and networks are dynamic and ad hoc, manual configuration quickly becomes too complex. The combination of the sheer number of nodes with the heterogeneity and dynamics makes it almost impossible for the system administrator to ensure good configuration or even ensure correct operation. To achieve the vision of pervasive computing, nodes must automatically discover their environment and self-configure, then must automatically reconfigure to adapt to changes.

Protocols such as DHCP, DDNS and mDNS provide some degree of host autoconfiguration, but network administrators must still configure information such as address pools, routing protocols, or OSPF routing areas. Only limited progress has been made to automate the configuration of routers, servers and network topology. This dissertation proposes the autoconfiguration of most host, router and server information, including the automatic generation and maintenance of hierarchy, under the same architectural, algorithmic and protocol framework. The proposed unified framework consists of modules (DRCP, DCDP, YAP, ACA) responsible for the entity autoconfiguration and from a modified and well adjusted general optimization (Simulated Annealing) based algorithm for the domain autoconfiguration. Due to the generality of the optimization algorithm, the generated hierarchy can improve dynamically selected network performance aspects represented by appropriately designed objective functions and constraints. An indicative set related to the physical characteristics of the domains and node mobility is provided.

Even though SA has been adjusted for faster convergence, it may still be unable to capture the dynamics of rapidly changing networks. Thus, a faster but suboptimal distributed hierarchy generation mechanism that follows the design philosophy of SA-based mechanism has also been introduced.

Inevitably, due to network dynamics, the quality of the hierarchy will degrade. In such scenarios, the frequent reapplication of the expensive optimization based hierarchy generation is prohibitive. Hence, for extending the domain formation framework, distributed maintenance mechanisms have been proposed for reconstructing the feasibility and quality of the hierarchy by enforcing localized decisions.

The proposed framework has been applied to provide solutions on some realistic network problems related to hierarchical routing and topology control.