TCP Wrappers and Server Security

Systems that act as servers on a network become extremely vulnerable. The security of the servers becomes as important as the security of the network. Organizations owning web servers need to keep pace with all the threats that can possibly affect a server. Also, the servers need to be updated with security patches regularly.

One of the preventative methods is the usage of TCP wrappers. TCP wrappers help control the access to IP servers. These wrappers work in conjunction with a set of access rules specified for servers and strive to meet them. They keep logs of network activity and record the host names and addresses.

The client using the applications on a server protected by TCP wrappers is unaware of this protective layer; TCP wrappers, thus, provide a seamless experience to non-malicious, authorized users. Also, the same wrapper can be used for different applications, making them extremely useful. The wrappers monitor the client-server activity just once at the beginning of a session, allowing them to function smoothly during the rest of the session. However, in cases where the server serves more than one client at the same time, TCP wrappers won’t be helpful as they stop monitoring after the initial contact of the server and its client. TCP wrappers will not recognize the consequent requests by other clients and will not monitor them.

Though they are not at the core of the security scheme for servers, TCP wrappers can aid the security of the simple client-server system by providing another layer of security.