What four major components does the H.323 standard define for real-time, network-based, interactive videoconferencing? What functions does H.323 Gatekeeper provide for H.323 videoconferencing clients? Describe the process by which an H.323 client registered with H.323 Gatekeeper on one network calls the e-mail alias of an H.323 client registered with H.323 Gatekeeper on another network. An H.323 client attempts to call another client by specifying the client's alias, someone@microsoft.com. Two e-mail address rules match the requested alias. The first rule specifies the suffix pattern microsoft.com and has a metric of 4. The second specifies the exact pattern microsoft.com and has a metric of 5. Which rule will be applied to the call? What is the benefit of a call routing rule configured to route to a gateway destination?