The Sydney-class, like many of the contemporary classes of that era, possessed several systems still in use during the 24th century, including the transporter system, the subspace radio, sensors and impulse engines.
The bridge was the command center of the Sydney-class.
Ships of the class
The name of this class is named after Sydney, Australia, with the USS Jenolan being named for the Australian tourist attraction, Jenolan Caves, located near there; visited by Naren Shankar and episode writer, Ronald D. Moore following a Sydney convention. (Star Trek: The Next Generation Companion)
The studio model was originally used for an orbital shuttle created for Star Trek VI: The Undiscovered Country, and was substantially modified with Constitution-class and Miranda-class components, notably the bridge module and nacelles, to enlarge the appearance of the shuttlecraft into that of a larger vessel with several decks.
The Sydney-class model (measuring 6½"x11"x4") was listed in the 40 Years of Star Trek: The Collection auction with an estimated sale price of $4,000 to $6,000; it sold for $22,000 ($26,400 with premium).