单项选择题 Which IP telephony deployment model uses an H.225 Gatekeeper-Controlled trunk for call admission control within existing H.323 environments?（）

多项选择题 Which two settings must be configured in order to use the GUI to configure Call Admission Control with voice applications?（）

多项选择题 When designing a converged network, which measures can be taken at the building access layer to help eliminate latency and ensure end-to-end quality of service can be maintained? （）