Progress Software recently released the second version of its ProtoSpeed distributed application debugging and monitoring tool for testing and deploying Internet or intranet applications. ProtoSpeed is actually a combination of three related but distinct components: a protocol interaction monitor/debugger, the JWatch remote Java applet debugger from Intermetrics and an environment for creating custom network monitoring applications.
ProtoSpeed 2.0 is available now for Windows 95 and Windows NT, with a version for Solaris in beta testing. I reviewed the Windows version on an NT 4.0 system. ProtoSpeed installs quickly from the supplied CD-ROM. The only problem I had with installation was the step in configuring the location of my Java Development Kit. If you have multiple Java Development Kits installed on your machine, you must configure the location of your preferred JDK (version 1.1.2 or newer) manually. In my case I had Symantec Café 1.8 and Symantec Visual Café 2.5 installed. Through some trial and error I discovered that I needed to specify the path to the VisualCaféPDE/Java folder in order to use the JDK that was supplied with Visual Café. Once this problem was resolved, the rest of the installation proceeded smoothly.
Application Traffic Viewing
The unique aspect of ProtoSpeed, and perhaps its most common use, is monitoring and debugging the information transferred between a client and a server. Typically, client/server developers use LAN protocol analyzers that eavesdrop on the network to monitor client/server interaction. Rather than eavesdropping, ProtoSpeed uses a server proxy to monitor the traffic between the client and server. A proxy is a server that intercepts all Internet requests, passes each request to the intended Internet server, receives the response and, in turn, forwards the response to the original requester. With the rise of corporate intranets and the firewalls to isolate them from the general Internet, most client applications now include support for proxies. A different proxy is required for each application protocol. ProtoSpeed supports the most common Internet application protocols, including HTTP for Web servers, FTP for file transfer, and SMTP, POP3 and IMAP4 for e-mail systems. You can run several different proxies at once for different protocols or ports. For example, if you are testing an e-mail package, you can run both an SMTP proxy and a POP3 proxy at the same time.
To use ProtoSpeed for Internet protocol debugging, you must configure your clients to use ProtoSpeed's server proxy. Complete instructions are included for configuring Netscape Communicator and Microsoft Internet Explorer browsers. You will need to consult your user manual for other clients, such as e-mail and FTP programs, to find the steps to configure them to use a proxy. Because the proxy receives and forwards each packet, you can set breakpoints that are triggered when a certain type of packet is received. When a breakpoint is triggered, the packet flow between client and server is suspended, and you can view or modify the packet contents before resuming operation. ProtoSpeed provides easy-to-use breakpoint dialog windows for each supported protocol. Using these dialogs you can select almost any possible packet condition. Figure 1 shows a breakpoint set for an HTTP interaction.
A big plus for ProtoSpeed over LAN analyzers and other protocol monitors is the extensive set of data content viewers for the complex data types often found in the protocol data streams. You can view ActiveX objects, Java class files, JAR and CAB archives, ZIP files, images and MIME attachments. Support for these most common data types makes inspection of downloaded Java applets and ActiveX objects for potential security problems a breeze. You can also easily use ProtoSpeed to debug problems with cookies, understand the loading order of items on a Web page, check the format of posted data and monitor for rejected requests and other error conditions. Figure 2 shows an HTTP packet trace when accessing the Java Developer's Journal home page.
Remote Java Debugger
To go along with its Internet protocol debugger, Progress Software bundles the JWatch distributed Java debugger from Intermetrics into its ProtoSpeed package. With this debugger you can debug multiple applications or applets, local and remote, running in a browser, outside a browser or on a server. The distributed Java debugger provides a source-level debugger and also the ability to debug Java programs where you do not have the source, such as applets downloaded off the Web.
The debugging functions commonly available in an integrated development environment debugger are also available in ProtoSpeed's debugger. You can display thread groups, threads, stack frames, variables, packages, classes and methods. You can set breakpoints, single-step, run, pause and kill threads. If source code is available, it's displayed allowing line-by-line debugging. There can be multiple windows, each focusing on a different thread, or multiple windows for the same source file.
The remote Java debugger component of ProtoSpeed is compatible with Sun's JDK version 1.1.2 or newer, and can debug applets and applications running under either the Sun JVM (e.g., under AppletViewer) or Microsoft's JVM that is part of Internet Explorer.
Custom Network Event Monitoring
The most advanced feature of ProtoSpeed is its Network Event Manager. This manager lets you take advantage of ProtoSpeed's interception of network traffic to write your own packet monitoring code. As each packet is received and processed by ProtoSpeed, your handler is called to continue processing. These handlers can be running on the same machine as ProtoSpeed or on a remote machine. They can be written in Java or other languages such as Visual Basic. While quite powerful, this feature is probably beyond the needs of most developers.
ProtoSpeed is one of the best client/server traffic monitoring tools available. It is an essential tool for network developers, network managers or anyone else needing a clear understanding of exactly what information is being exchanged between their clients and servers.
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