IHMAS Internal Architecture

The distributed IHMAS architecture is proxy-based and exploits application-layer media gateways that act as autonomous proxies at client access localities to relieve MN/CN application components from complex adaptation operations on multimedia flows.The following figure depicts the main IHMAS components and their interactions.

The IHMAS architecture consists of three main components that interwork to handle the two core management functions: vertical handoff prediction and multimedia session adaptation.

• Vertical handoff prediction is realized by the Vertical Handoff Predictor (VHP) that extends the IMS Client with lightweight and completely decentralized handoff prediction via only local access to client devices.
• Multimedia session adaptation involves two components:the AS for Service Continuity (ASSC), deployed at the MN home network, that participates to session signaling to implement our original IMS vertical handoff optimizations; and the Adaptation Media Gateway (AMG), an application-layer media gateway that enables dynamic content adaptation at the MN target network.