It all begins with endpoints

03.04.2006
The lowly endpoint has long been the Rodney Dangerfield of networking, getting no respect while shouldering critical tasks in providing services. But all that anonymity is becoming history as the demands of more robust services push the long-ignored endpoint into the network limelight.

The concept of endpoints has morphed with the maturation of networks and the services running on them, evolving from what was once simply defined as whatever is attached to the end of the network into the network's reason for being. The classic example of the endpoint was the POTS (plain old telephone service) phone, which defined network endpoints through the era of the Bells, from when Alexander Graham Bell summoned Watson to when Gordon Bell started preaching about parallelism.

The network endpoints required little in the way of management or security, the functional twins pushing them into prominence today. A phone number, or some other type of circuit hardware address, was all that identified network endpoints. No one thought of those very simple pioneering services in relation to the critical functions driving endpoint evolution now -- status, configuration, metrics, operations, events and security. Management and security for those early "dumb" devices were embedded in the network, centralized in the telco switch.

Enter the device endpoint, the next evolutionary step in the endpoint maturity model. Telephones added microprocessors and applications, like voice messaging and Caller ID, requiring a modicum of support to provide these new services. Early computers arrived, relatively crude single-tasking devices with simple network or dial-up services connected to bulletin boards. E-mail emerged as a communications tool that differentiated the digerati.

Device endpoints added some rudimentary management functions, mostly for simple status checks, configurations and operations needed to coordinate phones with the embedded network intelligence or modems communicating with remote servers. In the era of the device endpoint, the major diagnostic step was rebooting; there were no real-time configuration changes based on events. Endpoints were undiscovered by hackers, who were consumed with "phreaking" the phone network by breaking into network switches.

The application endpoint arrived with the client/server model and is the dominant endpoint paradigm for many today. Client/server ushered in the era of "lights out" computing and shifted network management from centralized network intelligence to the endpoints. For the first time, logical endpoints exercised real control over events, status and configuration for application transport and connection management. They do it for the network and its attached computing platforms.

Circuit-switched public telephone networks in the era of application endpoints were superseded in importance by packet-switched networks. Network management systems arrived and embedded management agents in distributed devices, clients and servers. Downloading patches and updating client software became routine, with applications configured and network traffic optimized for events or wall-clock times to optimize workloads. E-mail became a critical function, hackers discovered how easy it is to break through security perimeters, virus writers made security a corporate priority, and most people heard the term endpoint applied to networks for the first time.

The final step in the endpoint maturity model is the service endpoint, as defined by the W3C. In that definition, there is only one supercharged converged packet-switched network with a plethora of services replacing the mix of applications and agents that are old.

Endpoints have added policy management to constantly monitor changing metrics and events in real time, to control status and configurations for connections, services and presence. All services are delivered over component architectures, and endpoints are integral to managing service interoperation and enforcing security throughout the network.

We still are evolving the mix of network services in tandem with the service endpoint. Communications blur into messaging across multiple channels, including wireless, with real-time voice over IP, instant messaging, multimedia and videoconferencing. Real-time services place unique demands on connection and transport management of packet-switched networks, requiring smart and agile endpoints to maintain persistent service connections.

The big bang created the universe, millions of light-years wide, in a trillionth of a second, while network endpoints have evolved to prominence at a leisurely pace. The endpoints are out there now like logical pulsars and quasars marking the network service boundaries, telling us if we're expanding or contracting and how much bandwidth we will need for the journey.

Mark Willoughby, CISSP, is a 20-year IT industry veteran and journalist. Contact him at milloughby@earthlink.net.