FRAMINGHAM (03/13/2000) - Layer 2 or 3 switches: Switches, or data transfer devices, operating at Level 2 (data link) on Level 3 (network) of the Open Systems Interconnection communications standard.
Internet service provider (ISP): A company that provides links between its customers and the Web.
Router: A device that routes data packets between LANs or WANs.
Firewall: A network node set up as a boundary to prevent traffic from one segment from crossing into another; often refers to the boundary between a corporate network and the Web.
Proxy server: An Internet server that sits between users' PCs and the Web to keep employees from accessing undesirable Web addresses, improve performance by storing Web pages locally and hide the internal network's identity from hackersInternet Protocol (IP): The protocol, or rules, governing the transmission of data across the Internet.
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education institution in Bethesda, Md.