VoIP 1
VoIP VoIP VoIP/IN VoIP/IN 2
Traffic Data Voice Voice Data over Voice Time Data Voice over Data 3
End-user Demands Lower cost voice services MultiMedia services Simplification Carrier Demands Regulatory cost avoidance Lower start-up and operating costs Differentiated services Technology Improved compression techniques Improved silence suppression Enhanced prioritization schemes 4
Evolution of IP Telephony* PC to PC Internet - Intranet Internet Telephony Enabled PC to Phone Phone to Phone Internet - Intranet PSTN Internet Telephony Gateway POTS PSTN PSTN Internet - Intranet PSTN POTS IP Telephony Gateways 5
Voice Services Packet loss, delay Voice Compression Rate Compatibility Call Control(H.323) CODEC (G.723.1) Billing, etc Network Services Open Network Architecture Multi Network Services Flexibility Service Independent 6
ITU - International Telecommunications Union Multimedia security H.323 Signaling over IP or ATM Multimedia protocols Numbering Architecture IETF - International Engineering Task Force Web services PSTN/ISDN Iptel : IP telephony PINT: PSTN-Internet service Sigtran : Telephony signaling transport SIP : Session Initiation Protocol 7
ETSI - European Telecomm. Standards Institute TIPHON (Telephony and IP Harmonization Over Networks) SPS5 (UNI/NNI signaling aspects) 8
SG16 Multimedia SG2 Numbering SG11 Signaling SG13 Architecture ITU-T Recommandations Required Contributions T1 Integrated Keeper spec Global country code Collaboration RFCs TIPHON Naming/Addressing QoS Interoperability Requirement Megaco PINT IPTEL SIP IETF 9
SMF SCEF SMAF SCF SCP SDF STP SRF IP SSP CCAF SSF CCF CCF 10
Voice Circuit SSP STP SCP SDP SS7 Signaling Links STP SSP SCP SDP HOST IP SSP STP SCP SDP IP 11 Service Switching Point Signal Transfer Point Service Control Point Service Data Point Intelligent Peripheral
4) 5) DB SCP SDP SS7 network 3) SCP 6) SCP 2) 7) SSP 12
Service Agent Gatekeeper User GK H.323 Network GK gateway Media Gateway Controller MGCP Media Gateway 13
SG: Signaling Gateway MGC: Media Gateway Controller MG: Media Gateway PSTN H.323, SIP IP Device RTP/RTCP PSTN SSP SS7, Q.931 SG SCTP MGC SIP+ MGC SCTP SG SS7, Q.931 SSP Gateway MGCP, MEGACO, H.GCP/H.248 Gateway Bearer Channels MG RTP/RTCP IP Network MG Bearer Channels 14
services Call independent services Call state machine Operations on bearer Operations on media SE SC CC BC MC Services Service Control Call control Bearer Control Media Control 15 SE SC CC BC MC Databases, etc. terminal registration, call routing... Call setup/teardown, call hold. map call topology to individual media flows. properties of individual media flows. Ex. media encoding, QoS& firewall control
2. Locate domain for user B 1. Setup voice& video call to B 8. Send media to border entity 1 SC CC BC 3. Set up a call between A & B 6. Set up one audio and one video bearer between border entities 2&3 With QoS SC CC BC 4. Locate terminal for user B 5. Do you want a voice call from A? 9. Send media to border entity 4 MC MC IP terminal A 7. Setup QoS path between border entities 1 & 2 7. Setup QoS path between border entities 3 &4 IP terminal B Border entity 1 Border entity 3 Border entity 4 Border entity 2 16
VoIP IN VoIP VoIP IN. : VoIP 080 IN VoIP IN VoIP VPN VoIP. Global Intelligent Network service 17
IP Networks SCN(switched circuit Net) SCP SCP SCP VPN GNP Pre-Paid Card Service 800 Service VPN LNP GK PC - Phone Phone - Phone Phone - PC PC - SCN-PC SSP 18
SM CM MP SSP INAP/ TCAP PSTN INAP/TCAP ISUP DS0 SM CM MP M NNI H.225Annex G OSP H.225 (Q.931), H.245, H.450 GK SM CM H.248 H.248 RTP, T.120 MP M Service plane Signaling plane Media plane 19
SS7 SSP App SIGNALING GATEWAY MGC App ISUP MTP-3 MTP-2 MTP-3 MTP-2 IWF MTP3- AL SCTP UDP IP ISUP MTP3- AL SCTP UDP IP IWF = Inter-working Function MTP3-AL = MTP-3 Adaptation Layer 20
SG-11(Signaling) SS7 over IP or ATM Sigtran SG-16(Multimedia protocols : H.323) Megaco (H.gcp = H.248) SG-12(Numbering) SG-13(Architecture) 21
ITU-T SG11( ) : Signaling Support, IN and routing for services on IP-based network Questions : Q.5(IN CS), Q.22(INAP) CS-1(Capability Set 1) PSTN CS-2(Capability Set 2) N-ISDN CS-3(Capability Set 3) B-ISDN Request-to-Call-Back SCN Request-to-Call SCN 22
CS-4(Capability Set 4) B-ISDN INAP over IP, IP over ATM Scope IN CS-3 IN Support for IP connectivity Support for IN service request towards an IP network Feature End User Service Data Customization via an IP Network Request-to-Call Back IP (VoIP) / Request-to-Call IP (VoIP) Request-to-Fax / Request-to-Fax-Back Request-to-Hear-Content from IP Request-to-Hear-Content from SCN Internet Call Waiting Web Controlled PSTN Conferencing Service IP Gateway Selection(Internet Access Server,VoIP GW) 23
H.323 GK SCF PINT Gateway IN MGC IN H.248 MGC-MG SCF Gatekeeper SIP SCF CORBA/JAVA 24
Management Control Call/Bearer 25
SCF INAP CS3.2 SSF CCF mapping Extended Gatekeeper 'soft SSF H.323 Gatekeeper SIP Proxy Server PSTN/ISDN Network Gateway IP network 26
Circuit Switch Model SoftSwitch Model Controller SS7 Net Sig. Protocol SoftSwitch SCP Sig. Protocol SS7 Net T D M Line Card Time Slot Interchange Trunk Card T D M Subscribers IP/ ATM Access/Media Gateway Packet Data IP/ ATM Trunking Gateway T D M 27
Subscriber Data Base GK Virtual PBX Click to Talk H323 VoIP to VoIP Services VoIP H.323 - G H.323 H.323 28
Sigtran Signaling Transport Megaco Media Gateway Control Protocol PINT PSTN and Internet Internetworking Spirits : Iptel The Services in the PSTN/IN Requesting InTernet Services IP telephony 29
* SIP Progress Report, VON Europe 1999 PINT/SPIRITS To SCP/PINTgw SIGTRAN Media Gateway Media Signaling Controller Gateway Signaling to SS7 Gateway (ISUP/IP) Controller Gateway SIP Proxy SIP Proxy SIP PINT Proxy PINT Proxy MGC MGC SIGTRAN SG SG to PSTN MEGACO (SGCP,IPDC) Media Gateway Media Gateway IPTEL (GLP,BGLP) IP Network RTP PINT/ SPIRITS MG MG MEGACO 30 PINT Client PINT Client
Call Control from VoIP to PSTN from PSTN to VoIP Signaling gateway decomposition ISUP SG MGC MGCP H.GCP SIGTRAN H323 H.246 SS7 PSTN Voice circuit RTP VoPN H323 H.323 31
Prepaid VPN Follow-me 800 # - Call Centers Subscriber Data Base SCP GK TCAP TCAP H323 SS7 PSTN or GSM VoPN H.323 H.323 32
PSTN PINT services Internet call waiting Click-to-dial-back Click-to-fax Click-to-fax-back Voice-access-to-content Characteristics of PINT services Initiated by Internet users Use existing PSTN-IN services Internet is used only for non-voice interactions Voice (and fax) services are carried entirely over the PSTN. 33
Intelligent Network IP Network Service/Application Layer SDF SCF IF4 SRF IF1 IF2 PINT GW F PINT Protocol PINT Client F Call/Bearer Layer SSF CCF 34
Web Client HTTP Web Server + PINT Client Internet SIP/PINT PINT Gateway Central Office 35
Online Call Alert Subscriber CO-based Voice Switch ISP POP Intelligent Peripheral database SCP AIN Infrastructure VoIP Gateway Internet 36
Subscriber Data Base ISUP GK +SG MGCP H.GCP VPN Virtual PBX H323 / H246 SS7 PSTN VoPN H.323 37
SS7 Signaling Gateway SCP IP Telephony Server Application Protocols H.323 / SIP Media Controller Signaling Protocols IPS7 Media Controller Stimulus Protocols MGCP based IP Client Interworking Protocols Control Protocols MGCP IP Phone TDM Media Protocols RTP / RTCP TDM TDM Phone PSTN Circuit Switch Media Gateway IP Client IP Media Gateway PSTN Circuit Switch TDM Phone 38
VoIP IP SCN ITU-T : H.323 IETF : SIP VoIP SCN Global Intelligent Network. 39