Take responsibility for your outgoing network traffic If you install software that interacts with other sites over the network, you should be aware how it works and what kind of traffic it generates. If it has the potential to make thousands of requests to other sites, make sure it uses an HTTP cache to prevent inflicting abuse on other sites.

It is not appropriate to use these document types for live content. These are made available only for download, to support local use in development, evaluation, and validation tools. Using these versions directly from the W3C server could cause automatic blockage, preventing them from loading. If it is necessary to use schemata in content, follow guidelines to avoid excessive DTD traffic. For instance, use caching proxies to avoid fetching the schema each time it is used, or ensure software uses a local cache, such as with XML catalogs.