David M. Chess

The vision of autonomic computing

A 2001 IBM manifesto observed that a looming software complexity crisis -caused by applications and environments that number into the tens of millions of lines of code - threatened to halt progress in computing. The manifesto noted the almost impossible difficulty of managing current and planned computing systems, which require integrating several heterogeneous environments into corporate-wide computing systems that extend into the Internet. Autonomic computing, perhaps the most attractive approach to solving this problem, creates systems that can manage themselves when given high-level objectives from administrators. Systems manage themselves according to an administrators goals. New components integrate as effortlessly as a new cell establishes itself in the human body. These ideas are not science fiction, but elements of the grand challenge to create self-managing computing systems.

Mobile Agents: Are They a Good Idea?

Mobile agents are programs, typically written in a script language, which may be dispatched from a client computer and transported to a remote server computer for execution. Several authors have suggested that mobile agents offer an important new method of performing transactions and information retrieval in networks. Other writers have pointed out, however, that mobile agents introduce severe concerns for security. We consider the advantages offered by mobile agents and assess them against alternate methods of achieving the same function. We conclude that, while the individual advantages of agents do not represent an overwhelming motivation for their adoption, the creation of a pervasive agent framework facilitates a very large number of network services and applications.

Itinerant agents for mobile computing

Describes a framework for itinerant agents that can be used to implement secure, remote applications in large, public networks such as the Internet or the IBM Global Network. Itinerant agents are programs, dispatched from a source computer, that roam among a set of networked servers until they accomplish their task. This is an extension to the client/server model in which the client sends a portion of itself to the server for execution. An additional feature of itinerant agents is their ability to migrate from server to server, perhaps seeking one that can help with the users task or perhaps collecting information from all of them. A major focus of the article is the agent meeting point, an abstraction that supports the interaction of agents with each other and server based resources The article begins with an overview of the operation of an itinerant agent framework and a review of previous work. The authors consider likely applications of itinerant agents and discuss one specific example in detail. They give an architectural description of the structure of itinerant agents, the languages employed to create them, and the execution environments required at the servers; and also a detailed description of how an itinerant agent is processed at a server. Security issues are then discussed and finally they consider the technical advantages of the itinerant agent framework and the services it enables. >

An architectural approach to autonomic computing

We describe an architectural approach to achieving the goals of autonomic computing. The architecture that we outline describes interfaces and behavioral requirements for individual system components, describes how interactions among components are established, and recommends design patterns that engender the desired system-level properties of self-configuration, self-optimization, self-healing and self-protection. We have validated many of these ideas in two prototype autonomic computing systems.

Computers and epidemiology

Analogies with biological disease with topological considerations added, which show that the spread of computer viruses can be contained, and the resulting epidemiological model are examined. The findings of computer virus epidemiology show that computer viruses are far less rife than many have claimed, that many fail to thrive, that even successful viruses spread at nowhere near the exponential rate that some have claimed, and that centralized reporting and response within an organization is an extremely effective defense. A case study is presented, and some steps for companies to take are suggested.<<ETX>>

A Multi-Agent Systems Approach to Autonomic Computing

The goal of autonomic computing is to create computing systems capable of managing themselves to a far greater extent than they do today. This paper presents Unity, a decentralized architecture for autonomic computing based on multiple interacting agents called autonomic elements. We illustrate how the Unity architecture realizes a number of desired autonomic system behaviors including goal-driven self-assembly, self-healing, and real-time self-optimization. We then present a realistic prototype implementation, showing how a collection of Unity elements self-assembles, recovers from certain classes of faults, and manages the use of computational resources (e.g. servers) in a dynamic multi-application environment. In Unity, an autonomic element within each application environment computes a resource-level utility function based on information specified in that applicationýs service-level utility function. Resource-level utility functions from multiple application environments are sent to a Resource Arbiter element, which computes a globally optimal allocation of servers across the applications. We present illustrative empirical data showing the behavior of our implemented system in handling realistic Web-based transactional workloads running on a Linux cluster.

Security Issues in Mobile Code Systems

In mobile code systems, programs or processes travel from host to host in order to accomplish their goals. Such systems violate some of the assumptions that underlie most existing computer security implementations. In order to make these new systems secure, we will have to deal with a number of issues that previous systems have been able to ignore or sidestep. This paper surveys the assumptions that mobile code systems violate (including the identification of programs with persons, and other assumptions that follow from that), the new security issues that arise, and some of the ways that these issues will be addressed.

Security in an autonomic computing environment

System and network security are vital parts of any autonomic computing solution. The ability of a system to react consistently and correctly to situations ranging from benign but unusual events to outright attacks is key to the achievement of the goals of self-protection, self-healing, and self-optimization. Because they are often built around the interconnection of elements from different administrative domains, autonomic systems raise additional security challenges, including the establishment of a trustworthy system identity, automatically handling changes in system configuration and interconnections, and greatly increased configuration complexity. On the other hand, the techniques of autonomic computing offer the promise of making systems more secure, by effectively and automatically enforcing high-level security policies. In this paper, we discuss these and other security and privacy challenges posed by autonomic systems and provide some recommendations for how these challenges may be met.

Unity: experiences with a prototype autonomic computing system

The behavior of a system results from the behaviors of its components, and from the interactions and relationships among them. In order to create computing systems that manage themselves, we will need to design both the behaviors of the individual elements, and the relationships that are formed among them. This paper describes a research project called Unity, carried out at IBMs Thomas J. Watson Research Center, in which we explore some of the behaviors and relationships that will allow complex computing systems to manage themselves; to be self-configuring, self-optimizing, self-protecting, and self-healing. The four principle aspects of Unity that we examine are the overall architecture of the system, the role of utility functions in decision-making within the system, the way the system uses goal-driven self-assembly to configure itself, and the design patterns that enable self-healing within the system.

Server virtualization in autonomic management of heterogeneous workloads

Server virtualization opens up a range of new possibilities for autonomic datacenter management, through the availability of new automation mechanisms that can be exploited to control and monitor tasks running within virtual machines. This offers not only new and more flexible control to the operator using a management console, but also more powerful and flexible autonomic control, through management software that maintains the system in a desired state in the face of changing workload and demand. This paper explores in particular the use of server virtualization technology in the autonomic management of data centers running a heterogeneous mix of workloads. We present a system that manages heterogeneous workloads to their performance goals and demonstrate its effectiveness via real-system experiments and simulation. We also present some of the significant challenges to wider usage of virtual servers in autonomic datacenter management.