Punch is an exception to the normal rules, at it is the only Indirect Touch Spell.
Normal Rules:
You roll Unarmed + Agility +2 for a Touch Attack, they roll Reaction + Intuition. Net hits don't matter, and on a tie, you win.
You roll Spellcasting + Magic, they resist with Body or Willpower (+Counterspelling, if available)
Punch:
You roll Spellcasting + Magic, they roll Reaction + Intuition (+Counterspelling again). Net hits add to your DV.
They roll Body + Armor -Force AP to soak damage.
It's better to think of Punch as a point blank ranged spell than a melee attack, since you don't have to make an Unarmed test. If you did, the opponent would be dodging twice; once against your unarmed, and again against Punch, which doesn't make sense.