What are the three components in an MGCP environment? (Choose three)
A.
Gateway
B.
Gatekeeper
C.
Endpoint
D.
Call agent
E.
Proxy server
Explanation:
A typical MGCP gateway environment connects on one side with a public switched telephone network (PSTN), and on the other side with an IP network. Specializedcall agentapplications control the flow of media data across the distributed environment.Call agents determine the route that data follows as it flows through the system. Multiple call agents can control call processing and data transfer. These call agents use a separate protocol to synchronize with each other and to send coherent commands to modules under their control.
Each call agent usually controls a set of gateway applications, including at least onemedia gateway.
Media gateways convert media signals to an appropriate format depending on whether the signals are directed to a circuit switched network format or a packet switched network.Media gateways primarily perform audio signal translation functions in accordance with call agent commands.
Note:Gateways connected to an SS7 controlled network must also include at least one signaling gateway for controlling SS7 signaling.
The MGCP connection model consists of endpoints and connections.Endpoints represent physical or virtual sources through which data can flow(for example, PSTN ports on a media gateway). Call agents combine sets of endpoints under their control to create point-to-point or multipoint connections. Connections provide data paths for transferring and processing the data that flows through the gateway environment.
In the MGCP model, call control intelligence resides in the call agents, not in the media gateways. In effect, the MGCP standard defines a master/slave relationship between call agents and media gateways, where gateways execute commands sent by the call agents.
MGCP is a client-server protocol.The CA handles all aspects of setting up calls to and from endpoints.CAs or control servers provide the feature capabilities that a particular endpoint will be able to use. Endpoints connected to differentCAswill likely have a different set of features they can use. Since all of the call control features are in the control server, each control server vendor decides which features are most important, and therefore different control server vendors differ in “essential features.”
MGCP relies on a control server, or call agent (CA), to control call progression, tones to apply, and call characteristics. MGCP endpoints carry out instructions from the CA, which controls how calls proceed.