The system consists of a 75, 89 or 98cm Satellite dish antenna mounted on or near your premises.

The dish must have a clear, unobstructed view of the south-eastern sky at an elevation of between 20 and 30 degrees. Two coaxial cables connect the dish antenna to a satellite modem located inside the premises, which connects via USB to the workstation (for single users) or to the Orbitlink firewall/router in the case of multi users.

When a user requests information from a web site, a request is sent from the PC system to a satellite orbiting 22,300 miles above the equator. The signal is then relayed to the Network Operations Centre hub facility, which has a direct connection to the Internet. The hub establishes connection with the user's selected site, and then relays the reply back through the satellite to the user.

Like ADSL, our Orbitlink service is an asymmetrical service, meaning that proportionally more bandwidth is allocated to downstream traffic than to upstream traffic. Your Internet connection is "always-on", 24x7.

Downstream speeds, which affect the viewing of web pages or the downloading of files, are engineered for speeds up to more than 1000 Kbps,(depending on grade of service). Orbitlink offers 4 download speeds 400Kbps, 640Kbps, 800Kbps and 1 Mbps services, and can offer custom services with download speeds of up to 4 Mbps.

The upstream is a 128 Kbps burst technology and generally operates between 32 - 64 kbps. As with any Internet connection, actual speeds will vary based on usage and traffic patterns and will at certain times be faster than other times.

Connected directly to the Internet backbone is the NOC (network operations centre). At the NOC, data from the Internet is routed into the hub equipment for transmission out to the satellite and on to our subscribers. The hub handles the transmission and receipt of signalling to and from the subscribers, and handles the IP / DVB (Digital Video Broadcast) conversion. The hub converts IP packets into DVB (MPEG-2) packets and sends them out, through the satellite, to the subscriber. The equipment at the customer's site transparently converts the DVB back into IP and routes it to the appropriate user.

The NOC also receives the return transmission from the subscriber through the satellite. The return channel uses various transmission schemes to send data from the subscriber back through the satellite to the hub and on to the Internet. Depending on the application, these could include TDMA, CDMA, SCPC or Spread-Spectrum CDMA. The hub equipment demodulates the return channel transmission bursts and routes it as IP to the Internet backbone.

DVB, originally developed and proven by DirecTV, DISH and other commercial broadcasters, is also the protocol of choice for satellite data transmission because of the high efficiency it presents. Proprietary advanced spoofing technology is employed to provide IP transparency and increase throughput speed.