A novel method is developed to merge and disband groups in IP Multicast while retaining the original setup of their groups. It extends the semantic of joining or leaving a membership from discrete members to group members in IP networks.. It has minimal impact on existing multicast trees and does not affect the operations of multicast routing protocols and the Internet Group Management (IGMP). It incurs lower processing overheads by maintaining the merge status of groups at the network level instead of storing the status at application level. A prototype router and testbed have been implemented successfully to demonstrate the feasibility of the proposed solution and for performance evaluation. The proposed group connection management fills the necessary gap in the existing IP Multicast architecture, where the lack of graceful merging and disbanding methods present an obstacle for more creative and complex usage of group applications.