Software Product Description


The Network Detective's Assistant™ v1.2

by EMPIRICAL Tools & Technologies™


Dr. WATSON, The Network Detective's Assistant, is an integrated software program designed to place a wide range of powerful network diagnostic tools at its user's fingertips. It can be used to install, configure, troubleshoot and maintain multi­platform, geographically dispersed computer networks.

Dr. WATSON is based on many years practical experience with real networks and internetworks. After years of building and operating networks, such as the Interop show network, the authors of Dr. WATSON created a package containing the tools they always wished they had.

Dr. Watson is recognized by LAN Magazine as the product of the year in 1994 for network testing and diagnosis.

Dr. WATSON consolidates enhanced tools of proven use into a unified system that is easy to use, highly mobile and, can be used remotely in conjunction with third-party remote utility software.

Dr. WATSON is a collection of sophisticated tools intended to be used by people who have a firm knowledge of TCP/IP and NetWare networks.

Dr. WATSON was specifically designed to operate on standard IBM PC/AT compatible computers, including "laptop" and "notebook" models, running under the MS-DOS operating system, and equipped with almost any standard Ethernet adapter. No unusual operating systems or specialized hardware is needed. Because Dr. WATSON can operate on highly portable, battery powered notebook computers, it is easily carried to wherever it is needed.

With appropriate software "shims", Dr. WATSON may also be used on Windows 95, even while another TCP/IP stack is running.

Dr. WATSON attaches to a network by means of an Ethernet connection. It is not, however, limited, by the extent of the Ethernet. Rather, Dr. WATSON is able to reach out over the user's internet to probe devices no matter what their location.

Dr. WATSON is intended to be used on networks of any size. There is no inherent upper bound on the size of the network. Dr. WATSON was developed on the Internet, the world's largest computer network.

Dr. WATSON has very little startup delay; it can be put to work within seconds.

How Dr. WATSON Operates

Dr. WATSON interoperates with other network devices using the TCP/IP and Novell NetWare protocols. It is an active device, sending packets to other computers on the network and responding to packets received. Although Dr. WATSON does contain a tool to view traffic, it is not a mere protocol analyzer. Rather, Dr. WATSON deals with the network by interacting with it rather than simply viewing it. As such, Dr. WATSON is capable of substantially more sophisticated forms of information gathering and problem analysis than popular network analysis tools.

By means of these interactions, Dr. WATSON is able to perform a number of tests on behalf of the user. These tests allow the user to:

In addition, Dr. WATSON is able to act as an easily configured host. As such, Dr. WATSON can act as a target for protocol interactions and SNMP queries initiated by other computers.

Network Detective and the Toolbox

Dr. WATSON contains two distinct elements: Network Detective™ and the Network Detective's Toolbox. Both the toolbox and Detective are wrapped into a single program. The Network Detective, using both passive and active methods, operates without user intervention to discover and identify devices on the network. The user can control many of the Detective's operating parameters including the rate of packet generation, methods of inquiry used, and scope of inquiry. Detective data may be made visible on screen as it is collected and is also recorded in a file for subsequent analysis.

Once the Network Detective identifies a device, it builds a database entry for that device. This entry grows over time as the Network Detective learns increasingly more about the device. Among the information which the Network Detective may place into the database are:

The Network Detective's Toolbox consists of a collection of sophisticated user driven tools that initiate specific tests. The user may have many separate tests running at the same time. There is no need to wait for one test to complete before starting the next. To facilitate subsequent review, test results are recorded in a log.

Among the tools found in the Network Detective's Toolbox are:

These tools are described in more detail later in this document.

Network Detective

Dr. WATSON's Detective is an automatic tool which will discover devices on the network and perform inquiries to build a database describing the existence of each device and its characteristics.

Reachability tools:

The single most important task of a network is to carry data from one location to another. Dr. WATSON includes a rich set of reachability tools which can be used to determine whether it is possible to "reach" across the network to communicate with another device.


IP over Ethernet RFC894
Address Resolution Protocol (ARP) RFC826
IP (Including subnets and classless routing.) RFC791, RFC950
Internet Control Message Protocol (ICMP) RFC792.
Simple Network Management Protocol (SNMP).
(Agent and manager roles are supported.)
RFC1157, RFC1155
User Datagram Protocol (UDP) RFC768
Domain Name System (DNS) RFC1034, RFC1035
Routing Information Protocol (RIP) RFC1058
Path MTU Discovery RFC1191
Router Discover Protocol RFC1256
Subnet Mask Request RFC950
Echo Protocol RFC862

Sample Uses

Dr. WATSON is very versatile. Because it consists of a collection of tools, the user may direct them to almost any imaginable use. To illustrate, here are a few potential uses for Dr. WATSON:

Supported Configurations


Dr. WATSON is provided with an Installation and User Guide containing installation and configuration instructions, detailed descriptions of all Dr. WATSON functions and problem solving techniques.

Product Support

Product support for Dr. WATSON is available via electronic mail and through Dr. WATSON's page on the World Wide Web:

Additional Software

Included with Dr. WATSON is the Crynwr Packet Driver collection. Empirical Tools and Technologies does not offer support for these drivers. However, such support is available from Crynwr Software.


Dr. WATSON is distributed as a self-extracting archive.

Ordering Information


Modified November 15, 1997