Web Services and Security
This section demonstrates how to incorporate security into your web service. We will do so in two ways: system security and application security. System-level security allows for restricting access to the web services from unauthorized clients. It is done in a declarative fashion, whereas application-level security is more flexible. With system-level security, you will most likely have the list of authorized clients’ IP addresses that you will let access your web service through the use of some configuration-management tools. With application-level security, you will incorporate the authentication into your web service, thus providing a more flexible configuration.
Because web services communication is done through HTTP, you can apply system-level security on web services just as you do for other web pages or resources on your web site.
There are a number of different ways you can secure your web services. For a B2B solution, you can use the IIS Administration Tool to restrict or grant permission to a set of IP addresses, using the Internet Protocol Security (IPSec) to make sure that the IP address in the TCP/IP header is authenticated. When you rely only on the client to provide the IP in the TCP/IP header, hackers can still impersonate other host IPs when accessing your web services. IPSec authenticates the host addresses using the Kerberos authentication protocol. You can also use a firewall to restrict access to your web services for ...