Woof Maxx,
There are two arteries, one on each side of the neck that have got to be closed off. On one side your bicep provides the pinch point and on the otherside it's your opponents own shoulder that clamps off the opposite side artery. For the choke to work you have to pull in with the bicep and put your other hand on the ball of your opponents shoulder and push in, effectively creating a vise like clamp that squeezes inward on both sides of the neck at the same time. If your opponent taps simply release the pressure. If your opponent doesn't tap it's because you don't have both sides clamped or if he goes limp after about 8 seconds you've successfully choked him out and you need to immediately release the pressure. As you apply the choke you must constantly monitor your opponents condition to ensure his safety. One, make sure you are not clamping down on his wind pipe as you squeeze, remember you are cutting off the supply of blood to the brain not air to his lungs and two make sure of his state of consciousness if he passes out and you don't realize it soon enough, well that's very dangerous. Holding a choke on for more than a few seconds can cause irreparable damage or death.
P.C.