11 - Information Technology Systems Infrastructure

Abstract

This chapter reveals that understanding information technology (IT) infrastructure is the basis for a successful integrated security system design. The reader should carefully read and understand this chapter in order to succeed as a designer. The Transact Protocol/Internet Protocol (TCP/IP) suite of protocols is the basis for IT networked systems. The chapter provides a description of how TCP/IP works. The designer will not achieve success without a comprehensive understanding of TCP/IP. TCP/IP operates on levels 3 and 4 of the Open Systems Interconnection (OSI) networking model. Data are encapsulated from the application program through the seven layers down to the network wire, sent across the network, and then DE capsulated back up the seven layers to the application on the other end. TCP protocol is able to fix bad communications. Other protocols in the TCP/IP family include User Datagram Protocol (UDP) and Real-Time Protocol (RTP), which does not fix bad communications but which are better suited for streaming data, such as video and audio. TCP/IP is also an addressing scheme. Each network connected device is assigned a TCP/IP address that identifies its location on the network. Addresses can be assigned either automatically or manually.