e data into meaningful information to support the organization. infrared The frequency range in the electromagnetic spectrum that is higher than radio fre- quencies but below the range of visible light. infrastructure The underlying structure or framework of the telecommunications system (e.g., switching, multiplexing, and transmission systems) that allows for the transmission of voice, video, and data. InP (indium phosphide) A semiconductor composed of indium and phosphorus that is used for making electronic and optoelectronic devices. InP is useful for optoelectronics devices such as laser diodes. Glossary input queue input queue A holding area for packets that come to the input port more quickly than the router can process them. Integrated IS-IS A routing protocol that combines routing for TCP/IP and OSI protocols. It is a superset of IS-IS, the OSI routing technology that combines the functionality of both OSPF and IS-IS. integrated photonic circuit The optical equivalent of an integrated circuit. The goal of integrated photonic circuits is to consolidate large numbers of separate optical devices into a sin- gle chip, customizing them for different applications to improve performance. interactive A term that describes the mode of transaction for a particular information service. An interactive service allows for both input and output. It is sometimes referred to as a two-way, as opposed to a one-way, service. interactive processing A processing method in which each operator action causes a response from the program or system. interconnected systems Systems that are linked together in local and/or remote networks. The exchange of data between systems in a network is through standard channels or through communications lines. Communication between interconnected systems normally occurs with- out manual intervention; it is provided by combined hardware and software that support the interconnection. interconnection The interworking of two separate wireline and/or wireless networks. Interconnection is used to refer