Dedicated SCPC or shared TDM down and SCPC return link for customers located in Southern Africa

Washington USA - Vipersat VSAT hub

Located at New Skies' Washington teleport the hub acts as a vital communications and customer co-location facility.

The large VSAT hub dish operates cross-strapped transponders to the Southern Africa Ku band spot beam coverage on the NSS-7 satellite at 338.5 deg east (21.5 deg west) as shown on the right.

Satellite broadband service coverage includes Angola, Zambia, Zimbabwe, Malawi, Namibia, Botswana, Mozambique and South Africa.

Located at the large hub:

Located at your VSAT customer site

The hub modem also receives a inbound carriers from each remote site. 

Carrier sizes, either inbound or outbound, may be from 2.4kbit/s to 10Mbit/s bit rates.

The outbound carrier is normally shared amongst several sites.  For example you might buy 300 kbit/s downlink and then share this amongst 3 sites, each with 6 PCs.

Return link carriers to the hub are typically smaller capacity, e.g. 33 kbit/s. 

Lower bit rate return links are normally dedicated to assure high speech quality for VoIP calls and to avoid overheads due to TDMA which involves transmission in the form of a series of bursts with gaps in between and delays due to carrier recovery headers on the front of each burst.  TDMA also interferes with good speech quality for VoIP calls.  Return link bit rate needs to be approx one third of the outlink bit rate for mixed internet access and VoIP.  For VoIP alone the capacity needs to be the same each way. 

The hub modem is connected to the internet via a Cisco router to the main American internet backbone, for worldwide terrestrial connectivity.

The customer may connect a hub or switch or wireless router and as many PCs as required (up to 253 maximum).

The VSAT modem is remotely controlled and managed from Global Teleports (UK) at Brookmans Park (UK).

Monthly prices approx $700 per month per 100kbit/s.  Lower prices, as much as half price, may be possible with extra large dish to allow 16-QAM modulation to work. The highest price corresponds to smallest dish.

Think in terms of these example options:

100kbit/s total:  60k downlink and 40k uplink, both dedicated, suitable for small internet cafe with 5 PC and 1 VoIP phone. 

400kbit/s total:  280k downlink shared 3:1 and three 40kbit/s dedicated uplinks, suitable for 3 schools or internet cafes, each with 8 PCs and 1 VoIP phone.