VSAT in Nigeria

What is VSAT? (Very Small Aperture Terminal).  In terms of technology and how could this help to set up ISP, IAP, ICP etc?
Who are the providers of VSAT?
What is the typical Service Licence Agreement (SLA) per month
Is there an althernative to VSAT?
Who are the ISP's in Nigeria today? And, which one of them is excellent and which one is formidable?
What are the deregulations in telecom industry today in Nigeria?



NB
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ISP (Internet Service Provider)
IAP (Internet Application Provider)
SLA (Service Licence Agreement)
ICP (Internet Content Provider)