tailieunhanh - cisco avvid ip telephony phần 4

Gatekeeper là một thành phần cần thiết khi thiết kế các mạng AVVID. Từ một quan điểm hội nghị truyền hình, gatekeeper là thiết bị sẽ cho phép hoặc từ chối yêu cầu cho cầu truyền hình, làm cho bản án để xem liệu có đủ nguồn lực để thực hiện hoặc chấp nhận một kết nối hội nghị truyền hình cụ thể. | Chapter 5 Voice and Video Gatekeeper Design Solutions in this chapter Understanding Gatekeeper Basics A Gatekeeper s Role in Voice and Video Networking Placing and Configuring Gatekeepers A Case Study 0 Summary 0 Solutions Fast Track 0 Frequently Asked Questions 131 132 Chapter 5 Voice and Video Gatekeeper Design Introduction Gatekeepers are an essential component when designing AVVID networks. From a videoconferencing perspective the gatekeeper is the device that will permit or deny requests for videoconferences making the judgment as to whether there are enough resources to make or accept a specific videoconference connection. When looking at the Internet Protocol IP telephony component of AVVID gatekeepers are commonly used in multisite distributed call processing scenarios discussed in greater detail in Chapter 11 . As in the videoconferencing design the gatekeeper has a set of values by which it will determine whether or not to allow a specific call regardless of whether the call is incoming or outgoing. By the end of the chapter you will have an understanding of the gatekeeper s specific functions where and to place the gatekeepers in an AVVID network and why as well as a comprehension of design considerations when placing gatekeepers for videoconferencing or for IP telephony purposes. Understanding Gatekeeper Basics This section of the chapter discusses the functionality of the gatekeeper and the purposes the gatekeeper serves. It examines the types of gatekeepers available and the way the gatekeeper interacts with other devices on the network. It also covers design considerations examining options that should be considered when designing your voice and video network. What Is a Gatekeeper The gatekeeper acts as an intelligent central point of control for a real-time multimedia network. It monitors endpoints and gateways as well as audio video and collaborative data calls. The gatekeeper can control based on its configuration what stations endpoints .