Physical-Layer Management Simplified By Enterprise Networking System

Most of today's networking equipment—such as switches, routers, and file servers—can be managed remotely by a variety of methods. The most basic networking aspect of this is the physical-layer interface that connects all network devices together. This is the lowest layer of the 7-layer reference model defined by the International Standards Organization's (ISO's) Open Systems Interconnect (OSI) group.

The need to remotely control this layer hasn't generally been considered very important by networking professionals. One company, Tech Laboratories of North Haledon, N.J., however, believes that the advantages of remotely managing this physical layer can be substantial, especially because the goals of network management are evolving from an equipment-centric to a service-oriented paradigm. As a result, the company has developed the DynaTraX Enterprise Management Solution (DEMS) as the answer.

As the company sees it, MIS departments are no longer just operation centers, but rather service providers governed by service-level agreements (SLAs) with their users. Therefore, network managers must have the ability to measure the quality and level of service which they provide, and Tech Laboratories believes its DEMS product provides these network managers with the answer to this problem.

The DEMS is a combination of a universal switching matrix, a user-friendly graphical-user interface (GUI), and an integrated database. All are in a standard 19-in. rack-mountable enclosure (Fig. 1). Located between network equipment and users (nodes), this fast system allows end-to-end software-based network configuration and management at the physical layer, in real time, with a switching latency period of just 90 ns at 0-dB insertion loss.

Last year, the company purchased the rights to the DynaTraX transparent physical-layer silicon switching matrix from NORDX/CDT, Montreal, Canada, a subsidiary of Cable Design Technologies Corp.

On the user side of the network, it can hold up to six 18-port plug-in distribution cards (108 ports at maximum). Also, the same number of distribution cards may be held on the equipment side of the network. In addition, the system accepts a test card that allows remote monitoring and diagnostics of the physical layer.

Remote management of networks using the SNMP over SLIP protocol and LAN management using the SNMP over IP protocol are possible. The DEMS is designed for applications in both token ring and Ethernet networks.

This solution is designed to fill the gap between many popular network-management platforms, like HP's OpenView, and the need for software tools to properly manage the network's physical layer. The system has the ability to bring down the management cost of the desktop computer by automating such tasks as configuration management, remote troubleshooting, and software distribution. Essentially, the DEMS consists of DynaTraX hardware, an element manager, a command-line interface, and a connectivity engine (Fig. 2).

The hardware is made up of a sophisticated silicon cross-connect switch with on-board cable-testing facilities. The element manager provides a GUI with capabilities of drop-and-drag configuration, plus the management of connections between devices and or data equipment.

The command-line interface provides a comprehensive scripting interface for task automation. Additionally, the connectivity engine manages communications with DynaTraX units via the SMNP protocol. It provides an application-programming interface (API) which third-party developers can use to manipulate Tech Laboratories' DynaTraX hardware.

The new system reduces the high cost of physical-layer maintenance and makes it easy to track network assets. It also simplifies the task of integration with management frameworks like HP's OpenView or other specialized applications for problem or fault management. The system provides automated cable diagnostics as well.

All network moves, additions, and changes are made under software control with no manual intervention needed in a typical wiring closet. Making and breaking network connections via software translates into easy access to an up-to-date status of network connections and the physical location of the network.

To make a connection or disconnection between the network equipment and a node, users simply click on the end connection points with a mouse and draw a line between them on their control PC. Also, with a click of the mouse, a domain view with all the information on a specific user (user name, network connection, assets, phone number, etc.) appears. If you drag the user to another work area, the application will make sure a network service is provided.

A full range of diagnostic testing also can be performed automatically, making proactive management of the physical infrastructure a reality. This is a very important feature because a great majority of network failures result from physical-layer failures. Some studies have shown that 70% to 90% of LAN failures can be attributed to "cabling screwups."

For example, the system's test card can be used to detect on-screen an open cable up to 1000 ft. and a short-circuit condition up to 330 ft. with an accuracy that's within 3.5% and a resolution of one foot. Peak differential impulse noise measurements can be made over two ranges of 50 to 150 mV and 150 to 500 mV. Capacitance values of the line are able to be calculated from 0 to 22 nF (in three ranges of 0 to 500 pF, 0.5 to 2 nF, and 2 to 22 nF) with an accuracy within 5% +25 pF. Furthermore, line impedance can be read out from 50 to 200 Ω with an accuracy within 5.5%.

Thanks to its software control of network connections at the physical cable layer, the DEMS affords the user significant security advantages. For instance, all network resources can physically be taken offline, right from the control PC, after hours and re-enabled in the morning. In other words, network information is literally switched off by the silicon cross-connect switch under software control.

The DEMS eliminates the need to send a technician to a remote location to get into a wiring closet. That's all done from the user's controlling PC through software.

Tech Laboratories Inc., 955 Belmont Ave., North Haledon, N.J. 07508; (800) 848-5468, (973) 427-5333; fax (973) 427-5455; Internet: www.techlabsinc.com. Contact Bernard Ciongoli or Pierre Bergeron.