Final answer:
The traditional enterprise Cisco management platform that does not support SDA and is browser-based is the Cisco Network Assistant.
Step-by-step explanation:
The traditional enterprise Cisco management platform that does not support Software Defined Access (SDA) and relies on a browser-based GUI is a) Cisco Network Assistant. Cisco Network Assistant is geared towards managing switches, routers, and access points in small to medium-sized businesses that do not require the advanced features of newer platforms like Cisco DNA Center, which is designed to work with SDA. Cisco Prime Infrastructure (Cisco PI) offers management capabilities covering both wired and wireless networks but is more advanced than Cisco Network Assistant and is being phased out in favor of Cisco DNA Center. Cisco IOS 15 is not a management platform per se; it is the operating system that runs on Cisco devices.