Chivu has returned to Inter having served the club both as a player and youth coach.
Inter goalkeeper Sommer told the club's match programme: "He's a complete coach, you can see it in the way he interacts with us on the pitch and in how he handles situations.
"He's very calm but also very attentive: he has a great mentality and energy."
Of his own form entering the new season, the veteran also said: "Calmness and clarity are essential in my role, as is knowing how to handle pressure.
"I've always paid particular attention to my footwork; it's a fundamental component for me. Since my youth years, I've worked hard to improve in this area, and I've been fortunate to have coaches who have valued this ability in me."