Classification of s filter by topology

Electronic filters can be classified by the technology used to implement them. Filters using passive filter and active filter technology can be further classified by the particular electronic filter topology used to implement them.
Any given filter transfer function may be implemented in any electronic filter topology.
Some common circuit topologies are:

• Cauer topology - Passive
• Sallen Key topology - Active
• Multiple Feedback topology - Active
• State Variable Topology - Active
• Biquadratic topology biquad filter - Active