This paper presents the design and implementation of the Intentional Naming System (INS), a resource discovery and service location system for dynamic and mobile networks of devices and computers. Such environments require a naming system that is (i) expressive, to describe and make requests based on specific properties of services, (ii) responsive, to track changes due to mobility and performance, (iii) robust, to handle failures, and (iv) easily configurable. INS uses a simple language based on attributes and values for its names. Applications use the language to describe what they are looking for (i.e., their intent), not where to find things (i.e., not hostnames). INS implements a late binding mechanism that integrates name resolution and message routing, enabling clients to continue communicating with end-nodes even if the name-to-address mappings change while a session is in progress. INS resolvers self-configure to form an application-level overlay network, which they use to discover new services, perform late binding, and maintain weak consistency of names using soft-state name exchanges and updates. We analyze the performance of the INS algorithms and protocols, present measurements of a Java-based implementation, and describe three applications we have implemented that demonstrate the feasibility and utility of INS.

Most network naming schemes force applications to specify the network location of resources they wish to use. However, applications typically want a particular service and do not know where in the network the service is located. We argue that applications should be able to simply describe their needs in an intentional name, and that the network infrastructure should be able to resolve this name to its network locations. To this end, we have designed and implemented the Intentional Name System (INS). In this thesis we present the design of a key component of INS: the naming scheme. We describe the expressive syntax of its intentional names and the data structures and algorithms it uses to perform the name-to-location resolution. We analyze these algorithms, describe a prototype implementation, and present performance results that show the feasibility of our ideas. Finally, we describe three applications that demonstrate the utility of intentional names.

One of the problems of middleware for shared state is that they are designed, explicitly or implicitly, for symmetric networks. However, since the Internet is not symmetric, end-to-end process connectivity cannot be guaranteed. Our solution to this is to provide the middleware with a network abstraction layer that masks the asymmetry of the network and provides the illusion of a symmetric network. We describe the communication service of our middleware, the Distribution Subsystem (DSS), which carefully separates connections to remote processes from the protocols that communicate over them. This separation is used to plug-in a peer-to-peer module to provide symmetric and persistent connectivity. The P2P module can provide both up-to-date addresses for mobile processes as well as route discovery to overcome asymmetric links.

Today's Internet naming scheme, the Domain Name System [28], implicitly assumes that applications want to reach an address, where the address signifies location in the network topology. Typically, applications desire either information or functionality, and do not often know the best network location that satisfies their needs. We argue that current efforts to efficiently enable new services such as mobility, group communication, resource discovery, service location, caching, etc. have been greatly hampered by the lack of a flexible naming system and the inability of the name resolution process to affect data routing decisions. Significant effort is spent in creating independent, but similar infrastructure for each situation.

This paper presents a introduction to the concept of persistent authenticated dictionaries. It describes the design of two such dictionaries, one based on red-black trees, and one based on skip lists. Finally, it presents measurements of an implementation of persistent authenticated skip lists compared to ephemeral (non-persistent) skip lists and red-black trees