A combination of hardware and anti-virus software to protect the Internet gateway. One example is McAfee WebShield Appliances, which McAfee claims is easy to install in any network. The function of gateway virus scanners such as McAfee is to scan email and Internet content before reaching the network, thereby providing immediate gateway security without the need for expensive IT investments. The main advantage of deploying gateway virus scanners lies in their centralized management scheme, which results in having only one installation at the gateway to be managed and updated, thus making it easier to keep virus tables and detection engines up-to-date. In contrast, locally installed virus scanners run the risk of not being updated on a regular basis. Network Associates Technology, Inc. McAfee WebShield Appliances. [Online, 2004.] Network Associates Technology, Inc. Website. http://www.networkassociates .com/us/products/mcafee/antivirus/internet_gateway/ws_appliances.htm.