The Sky Blues made it two from two in the Champions League with a 3-0 victory in France.
Speaking after the game, Guardiola said: "We played really well, we didn't concede much and we were in control, patient and aggressive without the ball. I'm so satisfied with the performance and result, it's always difficult to win away.
"We can play on both sides, we tried to play high and wide to stretch the pitch. Raheem Sterling was exceptional, Phil [Foden] as well. We didn't expect them to play five at the back until we saw the team. Porto was the same. As much as we play against five at the back we started to take the control and rhythm.
"We were so stable defensively. Aymeric [Laporte] was good, Kyle [Walker] is in the best form since we've been together, Oleksandr [Zinchenko] helped us, John [Stones] played good minutes. I'm so satisfied with the way we played."