ceives the acknowledgement, then and only then do the two com- puters establish a connection and carry on with the session using their unique address information. IP networks, the Internet in particular, behave in similar fashion as Ethernet. PRACTICAL IP AND TELECOM FOR BROADCAST ENGINEERING AND OPERATIONS All these types of transport work well for moving files, including hypertext markup language-coded pages, fixed images, and other static objects. Uncongested networks may even support low volume continuous signals such as produced by voice or telephone service over IP, and even "work okay" with higher bandwidth continuous signals. Make no mistake about it though, unstructured networks cannot be relied on for transport of continuous signal, high bit rate, valuable content such as audio, video, closed captioning, control, or other signals associated with, or embedded in, program content. Reliable, predictable, safe, and secure content transport requires net- work connections with sufficient bandwidth, grade, and quality of service (GOS, QOS). Even non-time-sensitive or non-real-time trans- port-so-called FTP-should be planned and implemented with care because of the size of the files and the time required to move them have significant economic implications. Obtaining sufficient bandwidth, GOS, and QOS is a matter of speci- fying and configuring LAN, MAN, and WAN network resources. Sufficient, continuous bandwidth means the network must exhibit bandwidth equal to or greater than the bandwidth of all traffic, not just program content if the network is required to accommodate email, web surfing, network management, and perhaps voice. Insuf- ficient network bandwidth results in denial of service or, at best, delayed service. Program content payload bandwidth is roughly equivalent to the sum of compressed audio, video, and other signals multiplexed into a program stream or included in a file object stored on the system. When more than one real-time stream is present on the interface simultaneously, the aggregate of a