Distinguish broadcast from interactive service

ASAL’s system description distinguishes broadcast services and VSAT services using Ku and Ka bands. A broadcast distributes a program from an uplink through the satellite to many receivers. A VSAT, or very small aperture terminal, belongs to a ground network whose service may need both sending and receiving. The antenna’s appearance alone cannot establish its access rights, available data rate or supported application.

The Algiers rooftop photograph was published in 2011, before Alcomsat-1 launched. It shows receiving equipment in a real urban setting, not verified Alcomsat users. Use it to compare physical equipment with the hidden requirements of a service: receiving a television program is different from uploading an assignment or participating in a conversation.

In a simplified broadcast example, a single 8 Mb/s encoded program is transmitted once to a beam serving one hundred receivers. Adding receivers does not require one hundred separately encoded 8 Mb/s streams in that same broadcast path. The example ignores overhead and other constraints; it explains a traffic pattern, not Alcomsat’s actual capacity.

For contrast, twenty independent 2 Mb/s uploads represent 40 Mb/s of offered traffic before overhead. These are different data streams that cannot be counted as one shared broadcast. Real networks may schedule access, apply limits or use different paths, so offered traffic is not automatically the delivered rate. State the traffic assumptions before comparing capacity requirements.

Count independent data streams

A recorded lesson download can tolerate a pause that would disrupt a live conversation. A two-way classroom session needs intelligible incoming and outgoing audio and video, acceptable response time and sufficient continuity. Watching a broadcast on the same premises does not test all those requirements. The appropriate evidence depends on what the users are trying to do.

ASAL’s first-year retrospective records Ku-band testing, broadcast trials and a November 2018 interconnection involving education and health establishments in Adrar and Algiers. Those dated milestones provide examples of distinct application paths. They do not establish present-day performance at every site. A new acceptance plan should name its endpoints and workload and specify what counts as success before the demonstration starts.