▁NASA ▁TV , ▁Pent agon ▁Channel , ▁An ten na ▁TV , ▁This ▁TV , ▁The C ool TV ▁and ▁the ▁Ret ro ▁Television ▁Network ▁( through ▁its ▁affili ates ) ▁are ▁examples , ▁international ▁news ▁channels ▁like ▁N H K ▁World , ▁France ▁ 2 4 , ▁i 2 4 news ▁and ▁Al ▁J aze era ▁English ▁until ▁the ▁launch ▁of ▁Al ▁J aze era ▁America ▁are ▁commonly ▁watched ▁this ▁way ▁as ▁a ▁result ▁to ▁the ▁lack ▁of ▁avail ability ▁on ▁cable , ▁DB S ▁and ▁IP TV . ▁ ▁Some ▁cable ▁prov iders ▁use ▁interactive ▁features ▁built ▁into ▁set - top ▁boxes ▁le ased ▁to ▁their ▁subscri bers ▁to ▁dist ribute ▁video ▁on ▁demand ▁services ▁within ▁their ▁internal ▁networks . ▁Many ▁prov iders ▁of ▁subscription ▁television ▁services ▁– ▁both ▁networks ▁and ▁system ▁operators ▁– ▁also ▁have ▁TV ▁Every where ▁services , ▁which ▁usually ▁mix ▁the ▁video ▁on ▁demand ▁model ▁with ▁live ▁streaming ▁capabilities ▁( allow ing ▁view ers ▁to ▁watch ▁broadcast s ▁from ▁over - the - air ▁networks ▁and ▁stations , ▁and ▁cable ▁channels ▁in ▁near ▁real - time ), ▁but ▁require ▁password ▁and ▁username ▁authentication ▁through ▁particip ating ▁pay ▁television ▁prov iders . ▁ ▁Internet ▁services ▁ ▁IP TV ▁( intern et ▁protocol ▁television ) ▁is ▁similar ▁to ▁a ▁cable ▁subscription , ▁but ▁instead ▁of ▁the ▁set - top ▁box ▁receiving ▁information ▁via ▁a ▁dedicated ▁wire , ▁video ▁is ▁transm itted ▁over ▁the ▁public ▁Internet ▁or ▁private ▁internet ▁protocol - based ▁network ▁to ▁a ▁set - top ▁box .