IDS stands for: Internet Distribution System.
It is also known as a synonym for ADS (Alternative Distributions System).
IDS describes the distribution via 3rd party websites. This includes online travel agencies (OTA), travel portals, travel search engines/ directories, online hotel consolidators, airline websites with online reservation options.
Examples: Expedia, Orbitz, Priceline, Hotwire, Booking.com, Opodo