Explanation/Reference:
Explanation:
This type of call needs a bridge of some sort to support a multipoint call. Multisite is the option key on an endpoint that enables that endpoint to support a multipoint call. These multisite enabled endpoints are useful, but have limitations on the amount of concurrent endpoints that can be in the conference.
Multiway™ is a Cisco TelePresence feature that allows the user to transfer an established point to point call to an MCU, so that more participants can join the conference.
Multiway system requirements
Your deployment must have the following components:
Cisco TelePresence endpoints that support Multiway™

Cisco TelePresence Video Communication Server (VCS)

Cisco TelePresence MCU

Reference: https://borderless-learning.com/instructor-picks/what-is-the-difference-between-multiway- multisite-and-mulitpoint/
http://www.cisco.com/c/en/us/td/docs/telepresence/infrastructure/articles/ cisco_telepresence_mcu_configure_multiway_kb_166.html