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��������� ���������� �
VoIP ����������������
2000. 2.10.
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! Introduction
! Standard Issue
! Voice over IP (VoIP) signaling
! VoIP and Intelligent Network
! All IP network (IMT-2000)
! Conclusion
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Voice ���� Data ������������ ����
Voice ���� ��������Data over Voice
Data ���� ��������Voice over Data
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SS7SS7
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Tandem/Toll Network
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SCPSCPSCPSCP
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Packet
GatewaySwitch
SoftSwitch
GatewaySwitch
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Packet
Next Generation Tandem Network
SS7
Packet-BasedTandem Network
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GatewaySwitch
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�������� IP-network
–PSTN
–IP router network–(WDM/SDH/ATM)
–DiffServ, MPLS,–Multicast
–LAN
–PC
–Digi-TV
–Wireless
–AAA
–Directories–DNS
–Billing,–Network management
–SLA–VPN
–IP/INsignaling
–RSVP–Mobile IP
–IPSec
–GPRS
–UMTS
–Wireless
Mobility management
Home Customer
Corporate customer
Customer using Mobile
–Mobile IP
–DSL
Telephone Customer
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Elements of IP TelephonyStandards Based Connections
! Control" Telephony Protocols
" IP Call Control Protocols
! Media" PCM streams
" IP Packets
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Control in IP Telephony
! Control" Telephony Protocols
• Standard worldwide protocols
– ISDN, Analog, CAS, SS7
" Network Protocols
• IP Call Control Protocols
– H.323
– MGCP
– Megaco, H.248
– SIP
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Media in IP Telephony
! Media" PCM streams
• Vocoding
• Echo
" IP Packets
• Jitter
• Delay
• Sequence
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VON �������� ��������������������
! ITU - International Telecommunications Union SG 16" multimedia ��� security� �� ��
" H.323
! IETF - International Engineering Task Force" web services PSTN/ISDN ���
" Iptel : IP telephony
" PINT: PSTN-Internet service
" Sigtran : Telephony signaling transport
" SIP : Session Initiation Protocol
! ETSI - European Telecomm. Standards Institute" TIPHON (Telephony and IP Harmonization Over Networks)
" SPS5 (UNI/NNI signaling aspects)
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VON Protocols of interest
! H.323 (ITU-T)" initial push for VON interoperability
" Multimedia session control - call control
! SIP (IETF)" Session Initiated Protocol – Call Control
" SIP/ SAP/ SDP
" SIP+ (MGC to MGC communication)
! MGCP (IETF : Media Gateway Control Protocol)" Decomposed gateway model
• media gateway controller (MGC)
• media gateway (MG)
• signaling gateway (SG)
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VON Protocols of interest
! MEGACO (IETF)" MEdia GAteway Control; Successor to MGCP
! H.248 (ITU-T) [formerly H.GCP]" ITU variant of MEGACO
! SIP-T (IETF, Cable Labs) [formerly SIP+]" Signaling between media gateway controllers
! SCTP (IETF Sigtran) [formerly MDTP]" Simple Control Transmission Protocol
" Transport PSTN signaling (SS7, Q.931) over IP
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Gateway Control Protocol Map
DSM-CCDSM-CCDiameterDiameter
SGCPSGCP
IPDCIPDC
MGCPMGCP
MDCPMDCP
MegacoPMegacoP
NCS Packet CableNCS Packet Cable
Megaco/H.248Megaco/H.248Agreement reached betweenITU and IETF to work to createone standard
H.GCPH.GCP
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IP Protocol Roadmap
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H.323 VoIP Stack
Data Appls QoSAudioVideo Control and Management
HTTP
T.120TCP
RTPRSVPRTCP
UDP
Suppl.H.245
SetupH.225
TCP
IP
GKRAS
UDP
G.7xxH.26x
MediaManagement
ConnectivityManagementCall ControlMobility
Management
Virtual PABX PersonalAssistant
UnifiedMessaging
IP CallCenter
ProtocolLayer
AbstractionAPI
Service Layer
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H.323 standards scopes
! H.323 defines" System-level characteristics of terminals, gateways,
gatekeepers, and MCUs
" Call signaling procedures (phases A-E)
" Refers to H.225 and H.245 specs
! H.225 defines" Packetization and use of RTP/RTCP
" Use of Q.931/2 and RAS messages
! H.245 defines" Procedures for use of Control Protocol msgs
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H.323 calling - the old way
! Gatekeeper discovery
! Endpoint registration
! Call setup
! Capabilities exchange
! Master/slave determination
! Open logical (audio) channels
! Call services (BW changes)
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Discovery and Registration
! Auto discovery
! Registration
Endpoint Gatekeeper
GRQ
GCF/GRJ
Endpoint Gatekeeper
RRQ
RCF/RRJ
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Call setup, direct call signaling
Endpoint 1 Endpoint 2Gatekeeper 1
ARQ
ACF
Setup
Call proceeding
Alerting
Connect
ARQ
ACF
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Call setup, gatekeeper-routed
Gatekeeper 1 Endpoint 2
ARQ
ACF
Setup
Call Proceeding
Alerting
Connect
Setup
Call Proceeding
ARQ
ACF
Alerting
Connect
Endpoint 1
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H.245 proceduresEndpoint 1 Endpoint 2Gatekeeper 1
MasterSlaveDetermination
MasterSlaveDeterminationAck
MasterSlaveDetermination
MasterSlaveDeterminationAck
Capabilities
CapabilitiesAck
Capabilities
CapabilitiesAck
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H.245 procedures, cont’’’’dEndpoint 1 Endpoint 2Gatekeeper 1
OpenLogicalChannel
OpenLogicalChannelAck
OpenLogicalChannel
OpenLogicalChannelAck
Contains EP2RTP Address
Contains EP1RTP Address
WHEW!FINALLY!
NOKIDDING!
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H.323 calling - the new way
! Gatekeeper discovery
! Endpoint (pre)registration
! Call setup with Fast Start" May tunnel H.245 over H.225, or
" Create a separate H.245 Control Channel
! Call services (BW changes)
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Fast Start and pre-granted ARQ
Endpoint 1 Endpoint 2Gatekeeper 1
Setup (Fast Start)
Call proceeding
Alerting
Connect
Only one of thesecontains Fast Start
elements
WATSON, COMEHERE! I NEED
YOU.IF YOU WISH TO
LEAVE A MESSAGEFOR MR. WATSON,
PRESS *1
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ITU-T H.323 V.3 Components
! H.323 Base document + Annexes" Annex E - signaling on UDP (for scalability)" Annex F - single use device (minimum stack) SET(Simple Endpoint Type)
! H.225 Call control" Signaling, packets, media streams, GK admission" Annex G. inter-domain management
! H.245 Channel control" open, close, negotiate capabilities (optional)
! H.235 Security! H.332 Multicasting to large groups (MCU)! H.450.1-9 Supplementary services
" transfer, forwarding, hold, park, wait
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H.323 v.3
! H.450.x - Supplementary Services" H.450.1 Signaling Framework
" H.450.2 Call Transfer
" H.450.3 Call Diversion
" H.450.4 Call Hold
" H.450.5 Call Park/Call Pickup
" H.450.6 Call Waiting
" H.450.7 Message Waiting Indication
" H.450.8 Name Identification Service
" H.450.9 Call Completion ( Busy, No answer)
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H.323 Network
IP-basedVoiceMail
ServerGate-
keeperMCU
VoiceFaxGWPBX
H.320GW CO
Video
ISD
NP
OT
S
Fire-wall
Server
IP LAN
H.450Call
Deflection
H.225.0Annex G
Inter-Domain
H.323Annex E
UDP signaling
H.323 Annex D (T.38 Fax) H.323 Annex F (Simple Endpoint Types)
H.235Security &Encryption
ISU
P
CO
Gate-keeper
EgressRouter
ISP
H.323end-point
H.323end-point
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Scope of H.248 : Trunk GW
Multi-Services Data Network(IP or ATM)
Voice Streams
SS7(ISUP)
MGC
SGW
MGC
SGW
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Scope of H.248 : Access GW
Multi-Services Data Network(IP or ATM)
Voice Streams
MGC MGC
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Gatekeeper across Domains
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Signaling Gateway
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SIP/ SAP/ SDP
! SIP – Session Initiation Protocol" Application layer signaling protocol" New IETF WG formed (SIP) (Came out of MMUSIC WG)" Text, HTTP-like" Extensions being drafted for Calling party privacy, distributed call
signaling (DCS), local number portability (LNP)" Direct competitor to H.323" SIP+ is now SIP-T (or SIP-BCP) for Telephony Interworking
! SAP – Session Announcement Protocol" Multicast multimedia session directory" Announcers and listeners
! SDP – Session Description Protocol" Not really a protocol" Also used by MGCP
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1
2
3
4
5
67
8
9
1011
12
SIP Client
SIP RedirectServer
SIP Proxy
SIP Proxy
SIP Client(User Agent Server)
Location Service
Request
Response
1. SIP User Agent sends INVITE request to local proxy2. Proxy queries DNS to find Server for called party
3. Server knows that user is logged on elsewhere and redirects the call4. Proxy checks DNS again and proxies request to correct Server
5,6. Server consults local DB to find “next-hop” server7. Server proxies request to local Server
8. Call proxied to User Agent9-12. User accepts call, ACK propagates back to caller
SIP call flow
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General ISUP↔↔↔↔SIP Conversion
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ISUP transparency (SIP bridging)
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ETSI TIPHON Goals
Charter:! Combine telecommunications and Internet technologies to enable
Voice over IP networks to interwork with Switched CircuitNetworks (SCN)
Goals:! Fast: Meetings every 2 Months and email exploders
! Focus on Services and Specifications
! Global World-wide Acceptance
! Service Oriented Solutions that can be provided by many types ofnetwork operators
! We do not re-invent existing standards (use IETF and ITUprotocols wherever possible)
! Based on H.323 series and existing SCN standards
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Technical Objectives & Structure
Define:! Requirements for Service Interoperability
! Global Architecture: interfaces and functions
! Call control procedures, information flows and rotocols
! End-to-End Quality of Service parameters
! Address translation between E.164 and IP
! Technical Aspects of Billing & Accounting
! Security Profiles and Procedures
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Technical Objectives & Structure
8 Working Groups:! WG 1: Requirements! WG 2: Architecture! WG 3: Protocols! WG 4: Naming, Numbering and Addressing! WG 5: End-to-End Quality of Service! WG 6: Verification & Demonstration! WG 7: Mobility! WG 8 : Security
Also:! Specialist Task Force (STF 114)! Special Rapporteur on security
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! Phase 1
! Phase 2
! Phase 3
! Phase 4
TIPHON Scope
call set-up
PSTN/ISDN/GSM users IP based users
IP NetworkPSTN/ISDN/GSM
usersPSTN/ISDN/GSM
users
call set-up
IP based usersPSTN/ISDN/GSM
users
PSTN/ISDN/GSM
IP based usersIP based users
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Next Generation IP NetworksPrimary Challenges of Real-time Services
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ITU-T IN CS ������������ � � � �
! ITU-T SG11���� WP4" CS-1(Capability Set 1)
• PSTN ��� ����� " CS-2(Capability Set 2)
• N-ISDN ��� �� ������ " CS-3(Capability Set 3)
• �� B-ISDN ��� ��� �� ������ ��� ��� �����
" CS-4(Capability Set 4)• B-ISDN ��� ��• IMT-2000 VHE � ��� �� • LAN Interconnect, INAP over IP, IP over ATM
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ITU-T Q.1244
! H.323 GK���� SCF ��������
! PINT Gateway���� IN ��������
! MGC���� IN ��������
! H.248 MGC-MG���� SCF ��������
! Gatekeeper���� SIP���� �������� SCF ��������
! CORBA/JAVA ������������ ���������������� �� !"�� !"�� !"�� !"
! �#$%�#$%�#$%�#$% &'&'&'&' ��������
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IN CS-4 �!"#�!"#�!"#�!"#
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VoDSL: Voice in Cells over DSL
DSLAM
DSL CPEincludingvoice ports
Internet
Class 5 LE
ATMnetwork
PhonesFaxetc..
! For CLECs to offer multiservice access to small-business.
! Can reach customers anywhere where ATM based broadbandaccess is available
! Easy evolution, replacing TDM transport with DSL
! Coppercom, Jetstream
DSL
TR008, GR-303 to VoATMconverter
GR-303
LAN
4 to 16 POTS lines
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VoDSL: VoIP over DSL using existingClass 5 LE
DSLAM
LAN
DSL CPE
Internet
PhonesFax etc...
! For CLECs to offer multiservice access to small-businesscustomers over IP
! Can reach customers anywhere where broadband IP servicesare available
! Insensitive to layer 2 technology
! IP QoS may require some attention
xDSL
GR-303
LAN
8 to 24 lines
Voice&Dataintergr.
IP
Class 5 LE
ATMnetwork
TR008, GR-303 to VoIPconverter
RAN
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Voice services provided by IPTelephony Gateways and Gatekeepers
DSLAM
Voice
DSLCPE RAN
IPT GWInternet
Gate Keeper
! Both traditional transport and switching replaced by newbroadband / IP technology components
! Today still work to do with QoS, standards and features.
! A possible longer term direction
! It could take some time before volume business emerge forthis solution
DSLIPATM
network
PSTN
LAN
Voice clients
��������� ���������� ��
Wireless Network "#"#"#"#
! Proprietary BSC/MSC architecture
! Wireless standards - TDMA/GSM, CDMA
PSTN
Airinterface
Framing T1/E1 voice, SS7 signaling,(64 kbps voice)
AnalogA interface
BSC MSC
Wireless Standards PSTN Standards
��������� ���������� ��
Objectives of Wireless/IP Networks
! Provide better solutions to existing markets" Cellular
" Wireless PBX
" WLL
! Leverage direct connection to IP telephonynetworks" Allows access to existing VoIP equipment and networks
! Reduce infrastructure cost" No need to be proprietary end to end
" Easier for application developers to add new features
��������� ���������� ��
Wireless/IP Network
! IP backhaul of compressed voice
! In-building/campus applications
! More efficient for mobile-to-mobile calling
InternetGate-way
Airinterface
Abis IP encapsulated voice
analog64 kbpsvoice
BSCfunctions
MSCfunctions
Wireless Standards
PSTN
VoIP Standards PSTN StandardsGatewayGateway
��������� ���������� ��
Other Factors• IETF (e.g., MGCP)
• Carrier Networkse.g. Sprint
• TINA-C
• ITU-T SG-16 H.323
• ATM Forum
All-IPStandard
3GPP2• TSG-S Core-IP Ad-Hoc
3GPP• IP Forum• Evolved GPRS?
IMT-2000 All IP Standard
3GPP2• TSG-P PN-4286 TSG-S IP for IOS• TSG-N Exploratory
��������� ���������� ��
Network Evolution and All IP - All IP Network
! The aim of the all IP architecture is to allow operators todeploy IP technology to deliver 3rd Generation services,that is an architecture based on packet technologies andsimultaneous real time and non real time IP servicesincluding telephony and multimedia.
! The characteristics of the all IP network" Integration of mobile telecommunications and Internet" Packet transport using IP protocols" IP based call control protocols" IP client enabled terminals" Real time IP capable radio access network and also other access
means including Cable and HIPERLAN
LGIC
��������� ���������� ��
IP Unifies Wireless Architecture
Services
Core Network
Access Network(s)
Subscribers
Cellular WiLL Enterprise Satellite WirelineCable
NetworkManagement
Internet
IP Backbone
VoiceServices
Dispatch DataServices
2-WayPaging
OperatorSupplied
3rd PartySupplied
Control PSTN
Gateways
Network Services
• Packet IP Backbone• Supports all Access Technologies
• Unified Network Architecture
• Common Services
��������� ���������� ��
FFirst draft architecture for all_IP networkwas completed
WWork within 3GPP TSGs and WGsproceed according the TSG-Sapproved R00 Project Plan
RRelease 00 specifications completedincluding all-IP option
TThe proposal for an All IP option within R00All IP option within R00 wasaccepted
June 99
July 99
Oct. 99
Dec. 99
Jan. 00
Dec. 00
Jan. ~ Dec. 00
33GPP All-IP network feasibility study started
PProject planning work for R00 is started
RRelease 00 service requirements available
Network Evolution and All IP3GPP UMTS Release 2000 milestones
LGIC
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3GPP Release 2000 Architecture
GfGi
Iu
GiMr
Gi
Ms
Gi
R UuMGW
Gn
Gc
Signalling and Data Trans f erI t f
SignallingI t f
T E MT U TR AN
Gr
SGSN GGSN
EIR
MG CF
R-SGW *)
M RF
Mult imed iaIP Netw orks
PS TN/Legacy /Ex ternal
A pplic ations &Serv ic es *)
M m
Mw
Legac ym obiles igna ling
N etwork
Mc
Cx
A lternativ eAc c essNetw ork
Mh
C SC F
C SC F
Mg
T-SGW *)
T-SGW *)
HSS *)
HSS *)
A pplic ations& Serv ic es *)
MS C s erv er GMS C s erv er
*) thos e elements are duplic ated f orf ilay out purpos e only , they belong to the s ame
logic al element in the ref erenc e model
McMc
D C
SCP
CA P
MGWNb
Nc
Iu
Iu
R-SGW *)Mh
CA PCA P
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Data Services BenefitsData Services Benefits• Access to Internet-based
applications & services
ChargingChargingGateway FunctionGateway Function
The Road to IP(Cisco)1st Phase: Packet Data Services
2.5G2G
ManagementManagement(SNMP)(SNMP)
DHCP ServerDHCP Server DNS ServerDNS Server
Security Security Server (RADIUS)Server (RADIUS)
Application ServerApplication Server
Voice Data
INServices
CircuitSwitching
NetworkFeature Server
GbGbPDSN/GSN
Enabling Data Services
CircuitNetworkCircuit Packet
Traffic
Packet Network(Internet)
RadioAccessControl
Value Chain
DataData
VoiceVoice
VPNVPN
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2.5G / 3G2G
INServices
ServicesManager
Circuit/SignalingG
ateway
FeatureServer(s)
NetworkFeatureServers
RNCS
3G
Enabling Integrated Voice & Data ServicesCircuit Packet
Traffic
The Road to IP2nd Phase: Full Suite of Integrated Services
VoiceVoice +
Data
DataData
Value Chain
VoiceVoice
VPNVPN
Packet Packet VoiceVoice
UnifiedUnifiedCommunicationsCommunications
Operator Benefits:Operator Benefits:•• Integrated Voice and Data Services Integrated Voice and Data Services
•• Capacity and Cost Advantages Capacity and Cost Advantages
•• Integrated Provisioning and Billing Integrated Provisioning and Billing
CircuitSwitch
CircuitNetwork
IP Network
IP RAN
IP RAN IP RAN
Packet Network(Internet)Packet
Gateway
RadioAccessControl
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Circuit/Signaling Gateway
Operator Benefits:Operator Benefits:•• Cap MSC Investment Cap MSC Investment
•• Peer-to-Peer Network Peer-to-Peer Network
•• Multimedia Services Multimedia Services
•• Realizing the Full Power of 3G Realizing the Full Power of 3G
Circuit Packet
Traffic
The Road to IP3rd Phase: True Peer-To-Peer Network
2.5G / 3G2G
INServices
ServicesManager
Circuit/SignalingG
ateway
FeatureServer(s)
NetworkFeatureServers
RNCS
3G
CircuitNetwork
IP Network
Packet Network(Internet)Packet
Gateway
IP RAN
RadioAccessControl
CircuitSwitching
Circuit/Signaling GatewayCan Substitute for
MSC Functions
DataData
Value Chain
VoiceVoice
VPNVPN
Packet Packet VoiceVoice
UnifiedUnifiedCommunicationsCommunications
MultimediaMultimedia
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