Deploying Transport-Level Security for SharePoint

The very nature of interconnected networks requires that all information be sent in a format that can easily be intercepted by any client on a physical network segment. The data must be organized in a structured, common way so that the destination server can translate it into the proper information. This simplicity also gives rise to security problems, however, because intercepted data can easily be misused if it falls into the wrong hands.

The need to make information unusable if intercepted is the basis for all transport-level encryption. Considerable effort goes into both sides of this equation: Security specialists develop schemes to encrypt and disguise data, and hackers and other security specialists develop ways to forcefully decrypt and intercept data. The good news is that encryption technology has developed to the point that properly configured environments can secure their data with a great deal of success, as long as the proper tools are used. Windows Server 2003 offers much in the realm of transport-level security, and deploying some or many of the technologies available is highly recommended to properly secure important data.

Realizing Security by Deploying Multiple Layers of Defense

Because even the most secure infrastructures are subject to vulnerabilities, deploying multiple layers of security on critical network data is recommended. If a single layer of security is compromised, the intruder has to bypass the second or even third level of security to gain access to the vital data. For example, relying on a complex 128-bit "unbreakable" encryption scheme is worthless if an intruder simply uses social engineering to acquire the password or PIN from a validated user. Putting in a second or third layer of security, in addition to the first one, makes it that much more difficult for intruders to break through all layers.

Transport-level security in Windows Server 2003 uses multiple levels of authentication, encryption, and authorization to provide an enhanced degree of security on a network. The configuration capabilities supplied with Windows Server 2003 allow for the establishment of several layers of transport-level security.

Understanding Encryption Basics

Encryption, simply defined, is the process of taking intelligible information and scrambling it so as to make it unintelligible for anyone except the user or computer that is the destination of this information. Without going into too much detail on the exact methods of encrypting data, the important point to understand is that proper encryption allows this data to travel across unsecured networks, such as the Internet, and be translated only by the designated destination. If packets of properly encrypted information are intercepted, they are worthless because the information is garbled. All mechanisms described in this chapter use some form of encryption to secure the contents of the data sent.