Part of SOAP's strength is its ability to work well over HTTP, the firewall-friendly protocol. Today, most firewalls are configured to allow HTTP requests to go out and responses to come back. SOAP can work in this environment with no modification to firewall settings. For example, Microsoft designed DCOM to extend COM over the wire, which means you can't use it to call remote procedures implemented by non-COM objects. In other words, you can't use DCOM from a client machine to call a CGI program running on a Unix server.
SOAP enables such interactions by being platform and object-model independent.
SOAP manages this feat by relying heavily on XML as a widely accepted, platform-independent standard. Platform independence offers tremendous value when it comes to integrating business applications both within an intranet and over the Internet. It also makes practical the paradigm of building applications composed of calls to many other applications that are somewhere on the Internet. Compare this to today's distributed applications, which consist of components that run entirely on servers within the intranet. 4 SOAP Toolkit Architecture 6 Switching to SOAP Get the code for this issue here .