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IP TELEPHONY THROUGH H.323 STANDARD

K.NIKITHAB-Tech 3rd Year

Information TechnologyAITS, Rajampet.

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CONTENTS

• INTRODUCTION• DIFFRENT TYPES OF IP TELEPHONY• WHAT IS H.323• H.323 COMPONENTS• H.323 ARCHITECTURAL MODEL• PROTOCOL SPECIFIED BY H.323• H.323 CALL ESTABLISHMENT• CALL TERMINATION • CONCLUSION

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INTRODUCTION

• Internet telephony uses the Internet protocol to send audio, video an data between two or more users in the real time.

• IP telephony is the integration and convergence of voice and data networks, services, and applications.

• The main motivation of development of IP Telephony is the cost saving & integrating new services.

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DIFFERENT TYPES OF IP TELEPHONY

• PC to PC• Phone-to-phone over IP• PC-to-Phone• Phone-to-PC

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PC TO PC

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Phone-to-phone over IP using Gateways

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Phone-to-phone over IP using Adapter Boxes

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PC-to-Phone or Phone-to-PC

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What is H.323• The H.323 standard for the transmission of real-time

audio, video, and data communications over packet-based networks based on IP telephony.

• H.323 is a standard produced by the ITU-T Study Group 16.

• Currently the most widely-supported IP telephony signaling protocol.

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H.323 Components• Terminals• Gateways• Gate keepers

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H.323 Architectural Model

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Gatekeepers• Address Translation• Admission Control• Bandwidth Control• Zone Management• Call-Control Signaling• Call Authorization• Call Management

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Protocols Specified by H.323• audio CODECs• video CODECs• H.225 registration, admission, and status (RAS)• H .225 call signaling• H.245 control signaling• real-time transfer protocol (RTP)• real-time control protocol (RTCP)

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H .225 call signaling• H.225 call signaling is used to set up connections

between H.323 endpoints over which the real-time data can be transported.

• Two types :– Direct call signaling– Gateway routed call signaling

H.245 Control Signaling• Capabilities Exchange• Logical Channel Signaling

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Real-Time Transport Protocol

• Real-time transport protocol (RTP) provides end-to-end delivery services of real time audio and video.

• RTP is used to transport data via the user datagram protocol.

Real-Time Control Protocol(RTCP)• RTCP provides control services for RTP.

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H.323 Call Establishment

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CALL TERMINATION ENDPOINT 1 GATEKEEPER ENDPONIT2

END SESSION COMMAND(1) END SESSION COMMAND(2) RELEASE COMPLETE(3)

DRQ(4) DRQ(5) • DCF(7) DCF(8)

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Conclusion Internet telephony is cost savings and integrating

new services. Internet Telephony is a powerful and economical communication options by combination of the telephone networks and data networks.

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QUERIES…..?

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THANK YOU