Once you have created services and Web applications, you need to monitor your site to make sure it continues to run smoothly. Based on this feedback you can tune your site to be as efficient as possible. The main factors you need to consider are performance, security, stability, and scalability. In order to understand these concepts, you first need to understand the ArcIMS architecture. After that, you can focus on tuning your site.

ArcIMS architecture

The first step in understanding the ArcIMS architecture is to become familiar with the terms ArcIMS Application Server, Spatial Server, Virtual Server, connector, and application developer framework. The best place to get started is reading ArcIMS architecture overview.

After you have reviewed the architecture, you should understand how to manage Spatial Servers and Virtual Servers. This is covered in the ArcIMS Help topics Managing ArcIMS Spatial Servers, Managing ArcIMS Virtual Servers using Administrator, and Managing ArcIMS Virtual Servers using Service Administrator. You may not need to change your configuration right away, but you should understand the concepts.

Tuning and monitoring your site

In a well-tuned site, you need to consider the following factors:

• Performance: you want to create an environment that produces the fastest responses possible. Your site must perform well, or people will not use it. Some aspects of performance you can control, especially when creating your services. You should review the Optimizing ArcIMS services checklist for steps towards improving performance. You may not be able to control some aspects of site performance such as the amount of traffic within your network or bandwidth of client machines. However, if you are aware of these environmental variables, you can create services that help mitigate them.
• Security: Your data is your most important asset, and you must protect it. You want to make sure your site is secure so that only authorized users are able to view and access your data. In addition, you want to protect your ArcIMS site from hackers, attacks, and bad requests. You can set security on ArcIMS services as well as your Web application. For more information on securing ArcIMS services, see Restricting access to ArcIMS services.

  In addition to restricting services, ArcIMS has additional mechanisms to protect your data and site. You can set parameters for limiting the number of features that can be returned in a request, determining whether geometry is returned in a request, and limiting the types of image formats. For more information, see Overview of securing your services and Web site.

• Stability: Many ArcIMS sites have a requirement to be online at all times, and users may make requests at any time of day. ArcIMS has several built in mechanisms to keep a site running all the time, but as with security, you need to protect your site from unexpected downtime. ArcIMS has support for failover and redundancy. It also has built in mechanisms for automatically restarting Spatial Server processes if one of the processes stops responding. For more information, see Overview of keeping your site running.
• Scalability: ArcIMS is built to scale to meet increasing demand. As the volume of requests increases, you need to manage your site to handle the new requests without degrading performance. You may need to add additional Spatial Servers and machines to meet demand. If you haven't already reviewed the ArcIMS architecture, now is a good time to read Overview of Spatial Servers, Virtual Servers, and ArcIMS services.

ArcIMS provides a number of options to help you tune your site by modifying ArcIMS Application and Spatial Server property files. The most common options are covered in the ArcIMS administration checklist. This checklist will step you through the properties you should consider to make your site as efficient as possible.