VoIP Signaling and Call Control

Transcription

1 VoIP Signaling and Call Control Cisco Networking Academy Program 1

2 Need for Signaling and Call Control 2

3 Model for VoIP Signaling and Call Control VoIP signaling components Endpoints Common control Common control components Call administration Accounting 3

4 Call Control Models H.323 SIP MGCP H.248/Megaco protocol SAP RTSP Cisco CallManager 4

5 Translation Between Signaling and Call Control 5

6 RTP Sessions 6

7 Call Feature Negotiation 7

8 Call Administration and Accounting Administration Monitors call activity Monitors resource utilization Supports user service requests Accounting Maintains call detail records 8

9 Call Status 9

10 Address Registration 10

11 Address Resolution 11

12 Admission Control 12

13 Centralized Call Control 13

14 Distributed Call Control 14

15 Centralized Call Control vs. Distributed Call Control 15

16 Configuring H

17 H.323 and Associated Recommendations 17

18 H.323 Adapted to IP 18

19 H.323 Terminals 19

20 H.323 Gateways 20

21 IP-to-IP Gateways 21

22 H.323 Gatekeepers 22

23 Multipoint Conference Components 23

24 Component Relationships for Call Establishment and Management Endpoint (gateway) to endpoint (gateway) Endpoint (gateway) to gatekeeper Gatekeeper to gatekeeper 24

25 RAS Messages 25

26 H.323 Basic Call Setup 26

27 H.323 Fast Connect Call Setup 27

28 Finding and Registering with a Gatekeeper 28

29 Call Flow with a Gatekeeper 29

30 Gatekeeper-Routed Call Signaling 30

31 Multipoint Conferences 31

32 Scalability with Multiple Gatekeepers 32

33 Call Flow with Multiple Gatekeepers 33

34 Survivability Strategies H.323 replication strategies include the following: HSRP Gateway preconfigured for two gatekeepers or for multicast discovery Multiple gatekeepers configured for the same prefix Multiple gateways configured for the same prefix 34

35 H.323 Proxy Server 35

36 Cisco Implementation of H

37 Configuration Example 37

38 Configuring the Gateways Gateway 1 38

39 Configuring the Gateways (Cont.) Gateway 2 39

40 Configuring the Gatekeepers Gatekeeper 1 40

41 Configuring the Gatekeepers (Cont.) Gatekeeper 2 41

42 Example: show Command 42

43 Configuring MGCP 43

44 MGCP and Associated Standards MGCP is defined in RFC 2705, October 1999 MGCP architecture and requirements are defined in RFC 2805, April 2000 Centralized device control with simple endpoints for basic and enhanced telephony services Allows remote control of various devices Stimulus protocol Endpoints and gateways cannot function alone Uses IETF SDP Addressing by E.164 telephone number 44

45 MGCP Components 45

46 Endpoints Eight types of endpoints are defined in RFC 2705: Digital channel Analog line Announcement server access point IVR access point Conference bridge access point Packet relay Wiretap access point ATM trunk side interface 46

47 Endpoint Identifiers 47

48 Gateways and Their Roles Trunk gateway SS7 ISUP Trunk gateway MF NAS Combined NAS/VoIP gateway Access gateway Residential gateway Announcement servers 48

49 Call Agents 49

50 Basic MGCP Concepts Calls and connections Events and signals Packages and digit maps 50

51 Calls and Connections 51

52 Multipoint Calls 52

53 Events and Signals Events: Continuity detection (as a result of a continuity test) Continuity tone DTMF digits Fax tones Hookflash Modem tones Off-hook transition On-hook transition 53

54 Events and Signals (Cont.) Signals: Answer tone Busy tone Call waiting tone Confirm tone Continuity test Continuity tone Dial tone Distinctive ringing (0 7) DTMF tones Intercept tone Network congestion tone Off-hook warning tone Preemption tone Ringback tone Ringing 54

55 Packages Basic packages (generic media, DTMF, MF, trunk, line, handset, RTP, NAS, announcement server, script) CAS packages (RFC 3064) Business telephone packages (RFC 3149) 55

56 Gateways and Their Packages 56

57 Digit Maps 57

58 Control Commands EndpointConfiguration (EPCF) NotificationRequest (RQNT) Notify (NTFY) CreateConnection (CRCX) ModifyConnection (MDCX) DeleteConnection (DLCX) AuditEndPoint (AUEP) AuditConnection (AUCX) RestartInProgress (RSIP) 58

59 Call Flows 59

60 Survivability Strategies 60

61 Cisco Implementation of MGCP 61

62 Understanding Basics of Cisco CallManager Basic CallManager Configuration for MGCP Gateway Support: 1. Create an MGCP Gateway 2. Configure the FX Ports 3. Test the Phones for Local Connectivity 62

63 Cisco CallManager Implementation and Call Flows Registration 63

64 Cisco Call Manager Implementation and Call Flows FXS Call Flow 64

65 Configuring an MGCP Residential Gateway ccm-manager mgcp! mgcp mgcp call-agent ! voice-port 1/0/0! voice-port 1/0/1! dial-peer voice 1 pots application MGCPAPP port 1/0/0! dial-peer voice 2 pots application MGCPAPP port 1/0/1! 65

66 Configuring an MGCP Trunk Gateway! ccm-manager-mgcp mgcp 4000 mgcp call-agent ! controller T1 1/0 framing esf clock source internal ds0-group 1 timeslots 1-24 type none service mgcp! controller T1 1/1 framing esf clock source internal ds0-group 1 timeslots 1-24 type none service mgcp! voice-port 1/0:1! voice-port 1/1:1! 66

67 Example: show Command Router# show mgcp statistics UDP pkts rx 8, tx 9 Unrecognized rx pkts 0, MGCP message parsing errors 0 Duplicate MGCP ack tx 0, Invalid versions count 0 CreateConn rx 4, successful 0, failed 0 DeleteConn rx 2, successful 2, failed 0 ModifyConn rx 4, successful 4, failed 0 DeleteConn tx 0, successful 0, failed 0 NotifyRequest rx 0, successful 4, failed 0 AuditConnection rx 0, successful 0, failed 0 AuditEndpoint rx 0, successful 0, failed 0 RestartInProgress tx 1, successful 1, failed 0 Notify tx 0, successful 0, failed 0 ACK tx 8, NACK tx 0 ACK rx 0, NACK rx 0 IP address based Call Agents statistics: IP address , Total msg rx 8, successful 8, failed 0 67

68 68