width Layer 2/3 edge device; switch or router; structured, continuous bandwidth Layer 2/3 edge device; switch or router; unstructured, discontinuous bandwidth Layer 2/3 core device; switch or router; structured, continuous bandwidth Layer 2/3 core device; switch or router; unstructured, discontinuous bandwidth PRACTICAL IP AND TELECOM FOR BROADCAST ENGINEERING AND OPERATIONS Content transport network characteristics revolve around two basic types of content: live, real-time, or so-called steaming video; and non-real-time, such as realized when a file containing content is transferred across a network using file transfer protocol (FTP) techniques. Given these characteristics, then it seems logical to sym- bolize content transport with two types of network facilities and services. Live, streaming content requires continuous, uninterrupted connec- tions with an equal amount of bandwidth. That's the theory; how- ever, in practice it's always prudent to leave just a tad of headroom. So how much is a tad? Practicality drives such in the form of how the service provider divides up the bandwidth and sells it. For example, a 10 Mbs ATM or IP network facility likely won't be precisely 10 Mbs. These animals usually break out in increments of octal numbers. So somewhere around 10 Mbs will be something like 10240000. If that is your choice of network transport channel, then the compression system output bitrate should be set at some number less than the channel rate. This parameter is also a victim of practical circum- stances as well because these devices commonly have to deal with octal numbers. So a tad in practice happens to be the difference between the highest speed the encoder can be set at, and the channel rate. (See Appendix II for an example of calculating payloads and matching channel rates.) Non-real-time content can be transported using continuous, uninter- rupted connections, but it can also be carried on discontinuous band- width connections, usually at lower cost and improved utilization of the facilities. Be 