Home » Cisco » 642-437 » Which two functions are associated with a voice gateway?
Which two functions are associated with a voice gateway? (Choose two.)
A. Switches voice channels between connected analog and digital voice circuits
B. Provides voice-messaging services to connected analog and digital voice circuits
C. Interconnects two logically separate VoIP networks
D. Negotiates endpoint capabilities
E. Controls opening and closing of logical channels that are used to carry media streams
Correct Answer: AE
Explanation/Reference:
Explanation: The basic function of a gateway is to translate between different types of networks. In a VoIP environment, voice gateways are the interface between a VoIP network and the public switched telephonenetwork (PSTN), a private branch exchange (PBX), or analog devices such as fax machines. In its simplestform, a voice gateway has an IP interface and a legacy telephone interface, and it handles the many tasksinvolved in translating between transmission formats and protocols. The gateway allows communicationbetween the two networks by performing tasks such as Interfacing with the IP network and the PSTN orPBX, Supporting IP call control protocols, Performing call setup and teardown for calls between the VoIPand PSTN networks by terminating and reoriginating the call media and signaling, Providing supplementaryservices, such as call hold and transfer, Relaying dual tone multifrequency (DTMF) tones, Supportinganalog fax and
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Cisco 642-437 Exam
modems over the IP network. http://www.cisco.com/en/US/prod/collateral/routers/ps5854/product_data_sheet0900aecd8016981 2.pdf
