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TrendCommunications
TrendCommunications+44 (0)1628 503500 +44 (0)1628 503500+33 1 69 35 54 70+49 (0) 89-32 30 09-30+1 256 461 0790+34 93 300 3313+91-22-28521059+86-10-8518-3141Infoline@trendcomms.comwww.trendcomms.com
International:United Kingdom:
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China:Email:
Web:
FTTx Summitby José M. Caballero ([email protected])
Triple Play business development
TrendCommunications
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© 2007 Trend Communications - FTTx summit - Munich June 2007
About Trend Communications
Trend Communications is an international company supplying hand-held test equipment and on-line monitoring systems to the communications market. Trend’s solutions are intended to cover businesses involved with broadband access, voice, datacom, network management, photonic transmission, metropolitan and mobile networks.
Trend has always been at the forefront of the communications test market, and our strength is based on the robustness and high quality of our products. Our solutions combine excellence and high technology with ease of use, covering such technologies as Triple Play, xDSL, 3G/UMTS, ISDN, IP, Carrier Ethernet, NG-SDH/SONET and NGN.
At Trend our mission is to be the preferred supplier of Field-Deployable Testers through innovative design and cost leadership.
Trend Communications is a subsidiary of IDEAL INDUSTRIES, INC.
The Triple Play Challenge
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What is Triple Play?
Triple play is a business concept; a bundle of services rather than a completely new development.
1. Triple play is not a new technology, but a marketing concept for delivering three services: broadband access, television and telephone services over a single access network.
2. If mobile services are included, the bundle is often referred to as Quadruple Play.
3. There are two concepts closely related to triple-play:• • • • Service bundling: all the services are bundled into a commercial product.• • • • Technological convergence: one network supports voice/data/video applications.
4. Triple play can be delivered over various network types - copper, fibre, coaxial and wireless.
5. Inter-operability is not a requirement, but IP is at the heart of every implementation.
VoIPIPTV Internet VPNVoD Mobile Gaming
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© 2007 Trend Communications - FTTx summit - Munich June 2007
Triple Play business: consumer view
Triple play, enabled by the network convergence, means: multiple services on multiple devices, supplied by one network and one vendor.
Consumer Needs- Anytime, anywhere- Tailored- Affordable
Multiple Services- Internet access- Telephony / Video calls - Television- Video-on-Demand
One Provider- One bill- One customer support- Integrated voice mail- One address book- Terminal convergence- Mobile bundling
Teruel TelecomsTeruel Telecoms
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Triple Play business: provider view
Telecom operators are embracing a new strategy to deliver new, thrilling services by means of next generation networks. This packet of services includes line rental and fixed telephony with a combination of Internet access, IP television, video-on-demand, entertainment applications and, eventually, cellular phone services.
Network Convergence- IP-centric- Packet-oriented- QoS-enabled- Multiservice- Multiterminal
Multiple Services- Internet access- Telephony / Video calls - Television- Video-on-Demand- Mobile bundling
IP
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Network Convergence and Device Diversity
Triple Play is not only a set of multiple information flows, but it is a way to make a wide range of devices and terminals manage data, audio and video applications.
Laptop MP3/4 TV MobileHand-held
Internet TV Music Games VoIP VoD
PDA
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Telecoms Deregulation
Advances in technology and new regulations have made ISPs, Cable and Mobile operators competitors of telcos in voice and data access services. So, companies that were originally in different markets, are now all racing to bundle and offer the same services, using their own version of a converged network.
Cable OperatorTelecom Operator
DOCSISFDM
VoIP
Internet Provider
DSL
TV
DSL (and Fiber)
DSLVoIP
IPTV
IPTV
Mobile Operator
GPRS
3G
GSMPCM
VoIP
VoiceData
Video
VoiceData
AnyIMSHFC
Telcos, Cable, Mobiles and ISPs Become Competitors
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The Business Challenge for Service Providers
Cable OperatorTelecom Operator
DOCSIS
TV
VoIP
Internet Provider
DSL
TV
DSL (and Fibre)
DSLVoIP
IPTV
IPTV
Mobile Operator
GPRS
3G
GSMPCM
VoIP
VoiceData
Video
VoiceData
AnyIMSHFC
Network Convergence
FDM
Threats• • • • Voice revenue drop• • • • Attacked by ISP in VoIP• • • • LLU (Local Loop Unbundling)• • • • High churn
Opportunities• • • • Triple Play
Threats• • • • Telcos video entry• • • • Access restriction
Opportunities• • • • Two-way upgrading
Threats• • • • ARPU drop• • • • Flat subs growth• • • • Fierce competition
Opportunities• • • • New video technologies • • • • 3G, Triple Play
Threats• • • • Limited market size• • • • Competition from ISPs• • • • Networks not owned
Opportunities• • • • More bandwidth• • • • Triple Play
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The Telecom market status
More competition leads to:• • • • More segmentation: smaller scale than before.• • • • Less differentiation: to meet the same customer requirement due to convergence.• • • • Low entry barrier: more players, business cycle shorter.• • • • Price reduction: low margin.
2004 2005 2006 2007 2008
Monthly World ARPU
10
50
30
20
40
TotalVoiceData
€
1000
Mill
2000 Mobile
Fixed
2006 year
World Subscribers
1980
Cable
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Competition: the voice market
Unfortunately for telcos, ISPs, cable and mobile operators are also offering phone services. The revenues of fixed telephony are declining, because mobile phones are so popular, and there is more competition now when cable operators also offer broadband access and voice services.
PSTN
2006 year1980
% C
alls
100%
0%
Mobile
VoIP
2006
Mobile45%
Fixed line55% VoIP
4% Skype PSTN
20%76%
2002 2003 2004 2005
100%
2006
70% 65% 60% 57%
Traffic in minutes (Western Europe)
Fixe
d lin
eM
obile
0%
55%
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Competition: Wire vs. Mobile vs. Cable
It is easy to understand that bundling has become a protective strategy for incumbent operators to keep in business by means of wireline access while for cable and competitive operators it is seen as a threat.
5% 10% 15% 20% 25% 30%
Homes using only mobiles (%)
Cal
ls in
volv
ing
mob
iles
(%)
UK
10%
50%
30%
SwedenGermany
NetherlandsGreece
DenmarkIreland
SpainFrance
Italy
Belgium
Austria Finland
Portugal
20%
60%
40%
35%
Mobile substitution, Oct. 2006
Cable subscribers (Millions)
Pen
etra
tion
(Cab
le/D
SL)
0.25
0,5
5 M 15 M 100 M
1
Spain UK
France
Holland
Italy3 M2 M1 M 4 M
Germany
Belgium
Austria
5US
Japan
RatioCable penetration, Dec. 2006
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The Driving Factors of Triple Play
Redefining the business• • • • Lower revenues: voice services are declining, data is a
commodity, ARPU is flat• • • • Social changes: personal telecommunication services
Increased competition• • • • Internet, Mobile and Cable operators get up to 2% of fixed line
subscribers per year• • • • New regulations: unbundling the local loop, wireless unlicensed
Network convergence• • • • IP-centric and QoS-enabled• • • • Access independent: Many alternatives are valid, i.e. ADSL2+,
VDSL2, FTTH, Wi-Fi, EFM
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Triple Play’s AimsDifferentiating services• • • • For better positioning, create a market, avoid head-to-head competition.
Churn prevention• • • • Gain customer loyalty with one package that includes all services.
Minimize costs• • • • Integrate infrastructure and human teams by using network convergence.
Gain new customers• • • • Face competition from cable companies for TV and video customers.
Promote Branding• • • • Cultivate the perception of the company as being able to supply any type of
telecommunication service.
Efficient Service improvement• • • • Use advanced management solutions for quick and easy provisioning.
New revenue stream• • • • By adding data and video services.
Increase profits• • • • By using legacy and innovative applications to raise the ARPU.
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Telcos’ StrategiesFocus on urban and high-speed connectionsThose customers are more likely to contract new bundled services and stay loyal.
Cost is a key factorResidential customers are very sensitive to cost when contracting commodities such as telephony, TV and broadband access.
It is Video, can’t you see!Only Video-on-Demand is really new. Television is not, because there are many services based on broadcast, satellite and cable.
The Mobile ConvergenceThe “mobile vs. fixed lines” time is over. Integration of both worlds is strategic.
Keep it simple and reliableOne bill, one provider is probably less important than a reliable service: but it should be simple to manage by the customer and easy to maintain by the operator.
Think TankNetwork convergence makes it possible to provision any type of telecom service.
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The Triple Play Market
Subscribers• • • • Yankee Group (Aug. 2006): The US market has been calculated at 32 million annually, with an
average operator spending rate of about $ 4 000 per subscriber• • • • Pyramid research (2006): World market 35 million dollars by 2010
ARPU• • • • Heavy Reading (2006): ARPU can be increased by 100% when bundled services are running• • • • Gartner research (2006): Monthly european ARPU for fixed voice, Internet and TV is €93,70• • • • Fastweb (Italy) obtains an ARPU of €900 a year
Revenues• • • • Forrester (2006): Initial cumulative loss higher than €3 000 per subscriber
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The Big Game
Although triple play strategies may start only with service bundling, migrating to an IP-centric converged network needs to be part of the strategy of the operators involved, in order to reduce the delivery costs and simplify the management structure.
3Gmultimedia
in/outdoors cells
Triple Play(voice, data, video)
Mobile bundle
Fixed bundleVoice
Broadband
Voice
SMS
TV
video
GSM+WiFi
VoD
Multiservice(TV, VoD, VoIP, Internet, Mobile...)
Multiaccess(copper, fiber, wireless)
One bill
One vendor
One network
Multiplatform(PC, TV, Mobile, Game Console)
Bundling
Convergence Support Provision
Competition, Target Customer, Segmentation, Timing, Cost, Tariff, Cultural
Triple Play Architectures
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Applications and Protocols
ATM / FR
WDM / Dark Fibre / Coax / Wireless/ Twisted Pair
TV
VoIP
VPN
Internet
Mobile VoDISDN
IPTV
VoIP
VPN
InternetTele-
IEEE 802.1Q
LAPS
MobileTriple Play
ISDNServices
Media
phone
VoD
Gaming
VoIPData
PseudowiresNetworks
Storage
UMTS Voice
Ethernet PHY
Ethernet MAC
PPP
RFC 2684
Ethernet MAC
- Consumer behavior- QoS & QoE Requirement- Time- Segmentation- Tariff- Billing
- Technology- Cost- Management- Convergence- Tariff- QoS Assurance
- Access Capability- Deployment Cost
IP
MPLS
PDH / SDH / OTNGFP
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Triple Play Network
This architecture overcomes most of the drawbacks of native Ethernet, including:• • • • Carrier class: scalability, protection, QoS• • • • Advanced OAM functions, both centralized (SDH-like) and distributed (Internet-like)• • • • Automatic topology awareness, billing
NG SDH/SONET layer
MPLS/VPLS layer
Carrier Ethernet
Optic/WDM layer
Metro/Core CPEAccessService Providers
MSSP
Internet
IPTV
VoIP
LSRLERLER
LSR
LSRLSR LSR
LSR
IP layer
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Access: Air, Copper, and Fibre Access
FTTN
Splitter
DSLAM
FTTC
FTTH/FTTP
ADSL
Modem
Switch
Fibre
ADSL2+/VDSL2
ONU
OLT150m
ADSL2/VDSL21500m
3000m
Modem
Modem
DSLAM
Fibre
Fibre/Ethernet
DSL
WiMAX
Switch
Bonding
(8 Mbit/s)
Ethernet(50 Mbit/s)
(24 Mbit/s)
(50 Mbit/s)
(100 Mbit/s)
Modem
(20 Mbit/s)
HFC (Cable)(30 Mbit/s)
Fibre
Fibre
PON
Coax Cable modem
Line head
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DSL: A Success
Latest improvements on DSL• • • • ADSL2: Real-time rate adaptation support and Inverse Multiplexing for ATM (IMA)• • • • ADSL2: Native support (no ATM) of packet-based services (for example Ethernet)• • • • ADSL2+: Higher bit rates than ADSL2, but less reach• • • • VDSL: Faster than ADSL, but it needs remote DSLAMs closer to the customers• • • • VDSL2: Matches Fast Ethernet rate at 100 m and has native support for packet-based services• • • • VDSL2: Asymmetric and Symmetric configurations, compatible with POTS and ISDN• • • • VDSL2: Needs remote DSLAM deployment and FTTN
DSL introduced
DSL Forum formed
ANSI DMT ADSL Standard
G.992.1 G.dmtG.992.2 G.lite
G.991.2 G.shdsl
5M subscribers
25M subscribers
G.992.5 ADSL2+G.992.3 RE-ADSL
G.993.1 VDSL
G.993.2 VDSL2100M subscribers
G.992.3 G.dmt.bisG.992.4 G.lite.bis
1989
1994
1996
1999
2000
2001
2002
2003
2004
2005
1.5 3.0 4.5 6.0Reach
1
10
100
Dow
nstre
am b
it ra
te
VDSL2VDSL
ADSL2+
ADSL2
ADSL
Mbit/s
km
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Optical Access in the Loop
• • • • Passive Optical Network (PON) is an optical technology for the access network, based only on passive elements like splitters. In a PON, the transmission medium is shared, and traffic from different stations is multiplexed. Due to the use of simple and inexpensive transmission elements and a shared medium, a PON is a cost-effective solution for the optical access network.
• • • • Active Ethernet is an alternative technology based on point-to-point optical links instead of a shared infrastructure such as PON. It can provide higher bandwidth per user than any other access technology, but it is also more expensive.
APON / BPON(legacy)
GPON(ITU)
EPON(ITU)
P2P Ethernet
Standard ITU-T G.983 ITU-T G.984 IEEE 802.3ah IEEE 802.3ahDownstream rate (Mbaud) 155, 622 1244, 2488 1250 1250
Downstream throughput (Mbit/s) 136, 543 1144, 2289 899 925Upstream rate (Mbaud) 155, 622 622, 1244 1250 1250
Upstream throughput (Mbit/s) 136, 543 572, 1144 836 925Downstream efficiency 87 % 92 % 72 % 74 %
Upstream efficiency 87 % 92 % 67 % 74 %Configuration or split ratio 1:32 1:32, 1:64 1:32, 1:64 (with FEC) 1:1 (point to point)
Range (km) 20 20 20 10Encapsulation ATM GEM / ATM Ethernet Ethernet
Encryption AES AES Not standard Not standardNetwork Protection Standard Standard Not standard Not standard
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Ethernet in the First Mile
EFM interfaces provide low and medium speeds when compared to the available LAN or WAN standards. The new interfaces, however, are optimized to be profitable in the existing and newly installed provider access networks.
0.11
10
100
1000
10000
1 10 100
Copper EthernetElectrical EFM
Electrical LAN
Carrier Ethernet
Optical LAN
0.01
LegacyEthernet
P2P Ethernet EPON
Bit
rate
(Mbi
t/s)
Reach (km)
1000BASE-T100BASE-T10BASE-T
1000BASE-X
Optical EFM
Reach (km)
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Triple Play: Access Alternatives
The access technology used depends on:• • • • Target bit rate or application to be rolled out• • • • Distance to the Central Office (CO) short distances enable xDSL; if longer then FTTx is a must• • • • Installed base, i.e. a lot of copper and good quality facilitate ADSL2+ and VDLS2 rollout• • • • Fiber availability close to the subscriber’s site makes FTTN installation easier• • • • Budget i.e. xDSL is inexpensive (if copper is available), fiber is not expensive, but digging is!
Triple Play
2000 m
5000 m
FTTx FTTH
bonded ADSL2+VDSL2
FTTx
FTTH
FTTN
VDSL2400 m
xDSL & FTTx
1500 m
CO
VDSL2
FTTB
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Network plan case studies
8 Mbit/s service
20 Mbit/s service 1000 m400 m
1000 m
FTTN
VDSL2 - 12MHz
400 m1000 m
FTTN
VDSL2 - 12MHz
bonding ADSL2+
VDSL2+
50 Mbit/s service
FTTN
400 m
VDSL2+
· 1 x SDTV (MPEG-2) + Data + VoIP· 1 x HDTV (MPEG-4) + Data + VoIP
· 1 x HDTV (MPEG-2) + Data + VoIP· 2 x HDTV (MPEG-4) + Data + VoIP
· 2 x HDTV + Data + VoIP
· 2 x SDTV (MPEG-4) + Data + VoIP
FTTH
FTTC
400 m
FTTH
VDSL2
FTTH
VDSL2+
FTTB
FTTH
1500 m
3000 m
400 m
bonding ADSL2+
1000 m
FTTN
CO
VDSL2 - 12MHz
400 m1000 m
FTTN
VDSL2 - 12MHz
ADSL2+
ADSL2+ xDSL
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Metro Ethernet Should Be Carrier Ethernet
Best-effort
UTP, Fibre
Multipoint
Bridging
VLAN
50 ms restoration99,999% availability
Connection MAN/WAN
Centralized / DistributedSeparated Data/ControlIntegrated
QoSSLA
Event detection
E-LineE-LAN
Fault propagation
Multitechnology
Carrier protection
Low-costSingle-ended testOptical integration
STP, RSTP
ManagementService
Reliability*
Architecture
Roll-out
Maintenance Data-efficient
DataInternetVoDVoIP
Applications
MonitoringService verification
Ethe
rnet
Car
rier E
ther
net
Triple play
(OAM)*
Free
Topologies StarRing
Tree topology
Meshed
Congestion
ConnectionlessBilling Fixed
Variable
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Ethernet Scalability Problems
Native Ethernet has important drawbacks:• • • • Connectionless: This is often an advantage, but it limits QoS and requires constant address learning• • • • Privacy/efficiency: Switches and bridges use broadcasting for learning (IEEE 802.1d)• • • • VLAN limitations of 4 094 identifiers cannot be used in a WAN (IEEE 802.1q) • • • • Non-hierarchical MAC addresses are flat, so the switching table does not scale well• • • • It takes seconds to restore the Spanning Tree Protocol (STP). It cannot match 50 ms!• • • • No Ring topologies can be used, because STP allows only tree or star topologies• • • • Limited QoS, because native Ethernet is basically a best-effort technology• • • • Poor Management of nodes, topologies, events, performance• • • • Network Demarcation, the CPE and the Operator network must be separated clearly
Switch
EthernetVLAN
Triple Play
Mapping in Frames
SDH NG3Play
Switch
Services
CPE CPENetwork Operator
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Ethernet in MAN/WAN
Giga Switch
Switch Dark Fibre
LAN
CWDM/DWDM
OADM
SDH
NG SDH
MSPPswitch
Ethernet
ADM
MSPPswitch
Ethernet
TDM
SAN
Router
SDH
NG SDH
CWDM/DWDM
Dark Fibre
TDM
IP
Ethernet PHY
Ethernet MAC
Dark Fibre
IP
WDM
Ethernet MAC
WDM
Ethernet PHY
IP
SDH/SONET
Ethernet MAC
Adaptation
NG SDH
IP
MPLS
Any PHY
MPLS
Ethernet MAC
MPLS works over any physical infrastructure.
A proper Ethernet service must keep the MAC layer end-to-end.
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Multiprotocol Label Switching
MPLS manages traffic streams by separating route selection and packet-forwarding functions.
Pseudowire Edge-to-Edge Emulation PWE3 require a Tunnel label, used for guiding the frame through the MPLS domain, and a VC label, used to identify each customer’s traffic matching an MAC, Port or VLAN tag to a constant label.
Including VPLS (the PWE3 multipoint implementation) the Metro Ethernet network can provide easily:• • • • QoS to support triple play services• • • • Increased scalability overcoming the MAC address explosion issues• • • • Integrated protection architectures• • • • Advanced management
SDH NG
MPLS domainLER: Label Edge Router
LSR: Label Switched Router
LSP: Label Switched Path
CPE
Triple PlayDSLAM
STB
POTS/ISDN
IPTV
VoIP
Internet
VoD
PWE3: pseudowires
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MPLS and QoS
• • • • Provides routing, not QoS• • • • Overcomes many IP scaling problems• • • • Flexible and efficient, increasing the performance of IP networks• • • • Makes traffic isolation per customer or flow possible• • • • Transparent to QoS protocols
Therefore MPLS makes QoS provisioning easier, but using tools like DiffServ, RSVP, or ATM
SDH NG
LERLSR
MPLS domain
LER: Label Edge Router
LSR: Label-Switched Router
LSP Label-Switched Path
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A New Generation of TDM Network Elements
Cro
ssco
nnec
t
Ethernet
PDH
SAN
DVB
Triple PlayFr
amin
g
SDH ring
SDH ring
Eth
PH
Y
Eth
brid
ge
MP
LS
GFP
-F
VC
AT
LCAS
SDH
SDH
TDM
Dat
a
Layer 2Processing
Layer 1Processing
Cro
ssco
nnec
t
Fram
ing
SDH ring
SDH ring
Eth
PH
Y
Eth
brid
ge
MP
LS
GFP
-F
VC
AT
LCAS
Layer 2Processing
Layer 1Processing
Pac
ketiz
er
Circuit-Emulationover Packet (CEP)
Multiservice Platform (MSP)
Enhanced ADM Packet ADM
Deploying Ethernet in MAN / WAN environments makes it necessary to develop new types of SDH
•••• Enhanced ADMs are like a traditional ADM, but they include Ethernet interfaces to enable access to new services, and TDM interfaces for legacy services.
•••• Packet ADMs have a configuration similar to enhanced ADMs: They include TDM and packet interfaces, but packet ADM offers common packet-based management for both new and legacy services.TD
MD
ata
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What is NG SDH?
Fundamentally NG SDH is a packet-enabled technology made possible by three elements:• • • • GFP (Generic Framing Protocol) is an encapsulation procedure for packet data, performing bit rate
adaptation, managing features such as rate adaption, priorities, channel selection and submultiplexing.
• • • • VCAT (Virtual Concatenation) is a mechanism that assigns granular bandwidth sizes rather than exponential provisioning of contiguous concatenation. This is why VCAT is flexible and efficient.
• • • • LCAS (Link Capacity Adjustment Scheme) modifies the allocated VCAT bandwidth dynamically by adding/removing members. LCAS is also being used to implement diversity for traffic resilience.
LCAS
GFP-F
Contiguous Concatenation Virtual Concatenation
GFP-T
Optical λ MACTunnel
λ
LSP
VLAN
VCG Tunnel LSP
Fibre
WDM
NG SDH
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Alternatives to QoS Control
1. Over-provisioning• • • • Traditional solution for private and public networks• • • • May work for a while; requires regular updates
2. Traffic Engineering (MPLS)• • • • Improves routing performance and indirectly helps QoS • • • • Compatible with most networking technologies and protocols
3. Resource Reservation (IntServ)• • • • End-to-end guarantee of QoS; needs a signalling procedure (RSVP)
4. Differentiated routing (DiffServ)• • • • Edge routers classify packets into priority classes
12~106 kbit/sBandwidth
Loss
Delay
Jitter
1%
150 ms
30 ms
VoIP 32 ~ 320 kbit/s
2%
5 s
Jitter buffer
Streamed MP30.005 ~ 10 Mbit/sBandwidth
Loss
Delay
Jitter
2%
5 s
Jitter buffer
VariableBandwidth
Loss
Delay
Jitter
Sensitive
Insensitive
Insensitive
Audio Video Data
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Integrated Services (IntServ)
Based on resource reservation using end-to-end signalling• • • • Applications require resource management• • • • Resource reservation is done per flow by means of Reservation Protocol (RSVP) signalling• • • • Guaranteed service and controlled load for QoS-sensitive flows• • • • Source-to-destination packet handling at each hop and per each flow• • • • It’s not very scalable: RSVP is end-to-end and too complex• • • • Large packet processing and resource reservation makes RSVP inappropriate for core routers
Source
PATHRESVDataDataDataPATHRESV
RESV Tear
RSVP
PATHRESVDataDataDataPATHRESV
RESV Tear
Destination
Initiation
Data transmission
Refresh
Termination
IP
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Differentiated Services (DiffServ)
Key QoS control is managed at the Ingress router• • • • IP packets are marked and classified into categories or DSCP• • • • In charge of packet access, shaping and policing
Core routers just forward packets• • • • Fast routing to the next hop (rather than end-to-end management like in RSVP)• • • • Packet scheduling per DSCP. No previous signalling, no resource reservation• • • • End-to-end QoS built with PHBs
DiffServ does not guarantee a QoS but manages flows differently• • • • Simple and scalable solution
Ingress Router
Egress Routers
Flow identificationPacket markingAccess control
Core RoutersTraffic schedulingPer hop forwarding
Data Flows
EF
AF1
AF2
AF3
AF4
BE
+ -
EF: Expedited ForwardingAF1-4: Assured Forwarding (x4)BF1: Best Effort (lowest priority)
DiffServ Routing
In Out
Queues
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Weighing the Options: Technology, QoS and Cost
The right architecture depends on many factors. Each business case must be evaluated independly:• • • • Environmental: competition, culture, affordability, consumer behavior• • • • Segmentation: niche, mass, residential, enterprise• • • • Differentiation: services bundle, content, language, premium or value price• • • • Technology: QoS with new & existing technologies and low network deployment costs• • • • Time to Market: when and where to launch• • • • Service Costs: leadership or premium
VoDCompetitorsVPNQoS
VDSL2
FTTH
FTTN NG-SDH
WDM
AD
SL2+ VPLS
Carrier
-E
TV
InternetMobile IPTV
BandwidthFinancial
ARPUCompeVoIPData
Market
Voice
titorsVoIPCost
VoDInstalled
base
VoD
Services
Budget
Triple Play Applications
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Tele-applications
Triple Play applications are often a combination of several types of information, and a number of parameters such as bandwidth, source/destination relationship, type of routing, QoS, and symmetry
conn
ectio
n tim
e
101 105102 107103 108104 109106 1010
101
104
103
102
1 kbit/s 1 Mbit/s 1Gbit/s
1 min
1 hour
24 hours
bit/s
HDTV
Hi-Fi
Gaming
VoIP
Webinar
Data
Data Storage
Graphics
Internet
TransactionsSurveillance
CCTV
VoD
bit rate
MP3 Datacom
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IP Television
IPTV is made with at least four component:
1. Video contribution, which may include television and video on MPEG demand applications. Contents is coded, formatted and streamed according the addressing scheme and the protocols to transport the signal and distribute the programs across the subscribers.
2. UDP is the most common higher-layer envelope to forward packets across the network.
3. Access network, audio an video packets reach the customer premises thought the access network which may be based on ADSL2, ADSL2+, VDSL2, FTTN, PON, or WiMax
4. Customer Premises, to reach the Set Top Box (STB) where are signals decoded and finally displayed on a TV or a PC. The Internet Group Membership Protocol (IGMP) is used for channel tuning.
Video Contribution Customer PremisesDistribution network
IP / VPLS STB
TV device
Broadcasters
Live TV
VoDEncoder
Access network
Router
PC
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IPTV delivery
The IP television is a recent achievement thanks to the development of the following technologies
1. Carrier Ethernet, that can guarantee seamless Video streaming over converged networks
2. New architectures for IP network to support differentiated QoS for video applications, and allow a bidirectional or interactive service between the Content Provider and the Subscriber
3. Availability of a new generation of high performance IP routers and Ethernet switches
4. Evolution of First Mile technologies (xDSL, FTTx, Wireless) than can deliver several Mbit/s
5. Rich middleware software that can differentiate each IPTV service implementing options like video on demand, pay-per-view, VCR, multiple definitions, etc.
CPEAccessAggregationDistribution
IP/MPLS
VoD
Metro
Head end
FTTN
FTTH
ADSL2+
STB
VoD servers
Contribution
Broadcast TV
TV studio
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VoD vs. IPTV
Video on Demand (VoD)• • • • Unicast Service• • • • Real-time QoS is not a must• • • • Pause, Stop, Backwards, Forward, etc. options controlled with RTSP protocol• • • • Rich middleware like subscription VoD, network video recorder and personal video recorder
IP Television• • • • Multicast Service• • • • Real-time QoS is required • • • • RTP & RTCP protocols for quality control• • • • Channel zap with IGMP
20062004
IPTV
10
Subscribers Millions
2008
20
30
20062004
Revenues MEur
2008
5
10
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IP Video Protocols
Digital video is encoded in MPEG-2, MPEG-4 or WM9 coding schemes.
For transmission in IP networks, the multimedia transport stream must be packetized.
UDP is the most common transport layer protocol for IP video applications. RTP over UDP is an alternative.
IP
UDPTCP
RTP/RTCP
Access
Application
IP suite
Signalling Video + Voice + Data
IGMP
RTSP Transport Stream
WM9 MPEG-2 MPEG-4
EthernetPPP
ADSL2+ Fibre 802.3ahVDSL2 FTTx WiMax
NG SDH Transport
VoD IPTV
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IP Video Protocols
• • • • Digital Video is encoded with the help of MPEG-2, MPEG-4, or WM9.• • • • Content – where, who and how• • • • Cost – competitive• • • • Quality – viewing experience• • • • Convenience – shifted time TV, PVR• • • • Coverage – accessibility (fixed line or mobile)• • • • DRM – business model
IP
UDPTCP
Access
Application
IP suite
Signalling IPTV (Video + Voice + Data)
IGMP
RTSP Transport Stream
MPEG-1 MPEG-2 MPEG-4
EthernetPPP
ADSL2+ Fibre 802.3ahVDSL2 FTTx WiMax
NG SDH Transport
RTP/RTCP
WM9
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Audio-visual Services and MPEGThe Moving Picture Experts Group (MPEG) is a working body within the ISO that is responsible for developing video and audio encoding, compression and standards for digital television delivery, IPTV, commercial advertisements and multimedia digital video applications.
1. MPEG-1 (1993), typical rates up to 1.856 Mbit/s• • • • Coding of audio/video for digital storage media• • • • Used in CD Video• • • • Video resolution, generally 352 x 240/288 • • • • MP3 is the audio draft of MPEG-1
2. MPEG-2 (1995), typical rates from 2 to 9 Mbit/s • • • • Rates generally around 4 Mbit/s with ADSL2+• • • • Video resolution generally 720 x 480, 720 x 576 or 544 x 576• • • • Used in Cable, DBS, DVD, VoD and HDTV• • • • When used with HDTV, MPEG-2 typically runs at 19.3 Mbit/s
3. MPEG-4 (1999), typical rates from 5 kbit/s to 10 Mbit/s• • • • Developed by the ITU to enable wireless single-user video services• • • • Mobile/POTS 5 kbit/s to 64 kbit/s• • • • Internet 64 kbit/s to 364 kbit/s• • • • Broadcast/VoD 364 kbit/s to 10 Mbit/s• • • • High efficiency for IPTV
Videoconference MPEG-4 (<0.384 Mbit/s)
0
1
1000
100
10
Mbit/s
.5.25
VHS video MPEG-2 (1-2 Mbit/s)
Broadcast TV PAL MPEG-2 (4-6 Mbit/s)
Professional TV PAL MPEG-2 (8-10 Mbit/s)
Broadcast H_DTV MPEG-2 (12-20 Mbit/s) DVB satellite multiplex MPEG-2 TS (27-40 Mbit/s) Contribution TV MPEG-1/2 (34-50 Mbit/s)
Contribution HDTV MPEG-1/2 (140 Mbit/s)
Uncompressed HDTV (1.49 Gbit/s)
Uncompressed SDTV (124-166 Mbit/s)
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MPEG2
Digital television requires that pictures be digitized so that they can be processed by computer hardware.
Each pixel is represented by:• • • • one luminance number, that describes the brightness• • • • two crominance numbers that describe the color of the pixel. • • • • 4:2:2 means crominance horizontally subsampled by a factor of 2 relative to the luminance, 4:2:0 the
factor is horizontal and vertically subsampled.
pixels
lines
Standard TV Digitalization (4:2:0 at 25 frames/s)Luminance: 720 lines x 576 pixels x 25 fr x 8 bits = 82,94 Mbit/s
25f/s
Crominance: 720 lines/2 x 576/2 x 25 fr x 16 bits = 41,47 Mbit/s
High Definition TV Digitalization1920 lines x 1080 pixels x 25 fr x 8bits = 1.49 Gbit/s
TV frame
(+) = 124,5 Mbit/s
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MPEG Compression
Compression is necessary to reduce the bandwidth requirements• • • • Lower SDTV: 24bit/pixel x 480x640pixels/frame x 30frames/s = 221,16 Mbit/s!• • • • Market moves toward HDTV therefore high efficient compression is necessary• • • • Pixel characteristics is correlated with neighbors then in some extend its value is predictable• • • • Human eye is less sensitive to detail near edges or around shot changes
MPEG uses two compression techniques:• • • • Discrete Cosine Transform (DCT), for intra-frame codec• • • • Motion Compensation interframe prediction
Higher HDTV
HDTV
Lower SDTV SDTV
.
Frames/s Lines/Frame Pixels/Line
Lower SDTV 24, 30 480 640SDTV 24, 30, 60 480 704HDTV 24, 30, 60 720 1280Higher HDTV 24, 30, 60 1080 1920
Pixels Broadcast MPEG-2 MPEG-4 WM9
SDTV 704 x 480 6 Mbit/s 3.5 Mbit/s 2-3.2 Mbit/s 2-3.2 Mbit/sHDTV 1920 x 1080 19.2 Mbit/s 15 Mbit/s 7.5-13 Mbit/s 7.5-13 Mbit/s
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MPEG Compression
ISO standard for Audio and Video compression and multiplexing
1. Spatial Processing or Intra-frame• • • • Using Discrete Cosine Transform (DCT) to remove high frequencies the human eye can’t see
2. Temporal processing or Inter-frame• • • • Looks for redundancies between consecutive frames to remove them
3. Variable Length Code• • • • Uses shortest encoding to reduce size
4. Run Length Encoding• • • • Large sequences of Zeroes are replaced
101101000000000000011010111110100100100100001000000000000000
10110110111101011111010010010010000111101
1. 2. 3. 4.
freq.
eye
sens
itivi
ty
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Intra-Frame DCT coding
Human eye is less sensitive for high frequencies.
A two dimensional DCT is performed on small block of 8x8 pixels. The magnitude of each DCT coefficient indicates the contribution of vertical and horizontal frequencies to the original image. Note that:• • • • DCT: Converts and image block into frequency component,• • • • DCT: does not reduce the size of the image, in fact increases it! from 8 bits/pixel to 11• • • • DCT tends to concentrate the energy into the low frequency coefficients matching eye sensitive• • • • The non uniform coefficient distribution is a result of spatial redundancy in the block• • • • The coefficient weight is done according human perception: high freq are coarsely quantized• • • • DC coefficient: is called when the value is 0• • • • The scanning and compression algorithm produces a variable length code• • • • The final coding results in a I-frame
641 41E 51E 4A2 F5 456 428 52
4A2 603 4A2 E39 23C 136 6 36
410 182 297 149 11 A1 2 1F
A7 49 10 1C 33 12 41 13
7F1 845 7F9 234 4F1 912 41 445
478 645 437 458 306 877 817 B3
282 564 252 52 67E 31C 1AE 11
134 7F1 541 349 156 52 3 21
25 1A 11 8 0 2 1 0
5 5 7 6 2 1 0 0
3 2 A 1 0 0 0 0
1 1 0 0 0 0 0 0
123 58 69 24 F 3 0 2
78 2E 21 6 1 4 3 1
1C 8 5 1 3 2 0 0
2 6 9 3 1 0 0 0
25 1A 11 8 0 2 1 0
5 5 7 6 2 1 0 0
3 2 A 1 0 0 0 0
1 1 0 0 0 0 0 0
123 58 69 24 F 3 0 2
78 2E 21 6 1 4 3 1
1C 8 5 1 3 2 0 0
2 6 9 3 1 0 0 0
Sequence of Images
Image Macroblock Block
Slide
16 pixel16
pix
els
8 pixels
8 pi
xels
DCT
8 bits/pixel
DCT coefficients8 bits/pixel 11 bits/pixel
Human eye is less
Weighting
sensitive to high freq.set 0 below perceptionand minimize high freq.
Compression
Zig/zag scan with detection of zerosHuffman encoding
IDCT
- horizontal freq. +
- vertical freq. +
m x n pixels
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Frame Types
I-Frames: Intra-frame coded independly to other pictures.• • • • Compression is achieved with DCT reducing the spatial redundancy but not temporal.
P-Frame: Predicted pictures can use previous I or P pictures for motion compensation• • • • Each block can either be predicted or intra coded
B-Frames: Bidirectional predicted pictures from previous or later I or P frames (never B-frame) for motion• • • • Each block can either be forward/backward/bidirectional predicted or intra coded• • • • Forward prediction requires to change the natural frame order causing a reordering delay at reception• • • • B-frames achieve the highest degree of compression, I-frames the lowest
6B 3P I
Size: = =
I
P
B
Independent
future pictures previous picturesactual frame
B-frames P-frames I-frames
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Temporal processing or Inter-frame
A Group of Pictures (GOP) is described the number of pictures (N) and the spacing of P pictures (M) in our sample GOP N=12 M=3.• • • • In theory, the number of B-frames that may occur between any two I- and P-frames is unlimited• • • • In practice, there are typically up to twelve P- and B-frames occurring between each I-frame. • • • • One I-frame will occur approximately every 0.4 seconds during video showtime.
to
t11
Presentation order
B1 B2 I3 B4 B5 P6 B7 B8 P9 BA BB PC
I3 B1 B2 P6 B4 B5 P9 B7 B8 PC BA BB
Group of Pictures
to
Bitstream order Display order
t11
reordering
Arrival order
futureprevious
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MPEG Stream Generation Scheme
Two type of streams can be generated with the same source signal:• • • • Program Stream, intended media with low errors probability like CD-ROM• • • • Transport Stream, for noisy medias i.e. Satellites, IPTV uses shorter packets and independent clocks
MPEG
Clock
Encoders
AudioVideoData
ESESES
Packetizers
PES
PES
PCR/SCR
DVD
PS
TS
Modulator
DVBChannel
Program 1
Program k
AudioVideoData
...
ProgramMPEG
PES Header PES Packet
PES: Packetized Elementary Stream
TS Header TS PacketAdaption Field AF stuffing
TS: Transport Stream
ES: Elementary Stream
1
1
2
2
3
3
Codified Audio, Video, Data stream
with PCR (4 bytes) (144 bytes)
Multiplex
2
CD
Distribution Network
DVD readerPhysical Transport
STB
TV
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MPEG-2 Transport Stream
• • • • PID=000: PAT - Programme Association Table, lists the PIDs of tables describing each programme.• • • • PID=001: CAT - Conditional Access Table, defines the type of scrambling used + management info.• • • • PID=X: PMT - Programme Map Table, defines the set of PIDs associated with audio, video, data...• • • • PID=010: NIT - Network Information Table, contains details of the bearer network used• • • • PID=Y: PES - Packetized Elementary Stream, each independent sequence of voice, video or data
4 bytes
PayloadHeader
184 bytes
Adaption field
Transport Scrambling ControlPID
Transport PriorityPayload Unit Start Indication
Transport error indication Sync byte
Adaption Field Control Continuity Counter
PID8 1 1 1 13 2 2 2
Transport
Transport
TP Header
AudioVideo
DataAudio
PAT table
- Network Info: PID=10- Program H: PID=306- Program X: PID=032- Program Z: PID=510
PMT table (per programme)
- Video: PID=160- Audio Spa: PID=234- Audio Fren: PID=233- Subtitle Eng: PID=237
Packet
Elementary Stream
TransportPackets
Stream
PES
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IGMP Snooping and Zapping Delay
IGMP snooping is a method for intelligent forwarding of multicast packets within a layer-2 broadcast domain. IGMP registration information is snooped to create a distribution list of workstations to know which end-stations will receive packets with a certain multicast address.
Channel Zapping IGMP is a test used to measure the delay that occurs when a user joins or leaves a specific multicasting group. In other words, it is an IPTV channel zapping measurement.
Originator Switch
without IGMP snooping
Originator
with IGMP snooping
Multicastagent
Multicastagent
Multicastagent
Join request
Join reply
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Examples of TV Strategies• • • • Operator A: Targets high-end residential customers with busy life style for a premium
charge (4-10 times more than cable) for TSTV, VoD and HSI access.• • • • Operator B: Differentiates itself by delivering 25-50 Mbit/s VDSL2 bandwidth with
HDTV content at competitive rates to raise barriers to entry and strengthen its position in the market.
• • • • Operator C: Targets the mass market by using DTT for broadcasting, delivering content via VoD to use less bandwidth and make QoS control easier. This significantly reduces costs and risks in early deployment.
• • • • Operator D: Delivers multicast services at lower prices than cable for the mass market, with attractive content to boost market share and revenue for the time being.
• • • • Operator E: Targets specific sport fans for mobile TV during major sports events. Uses DVB-H technology to differentiate the service.
• • • • Operator F: Targets enterprise customers by delivering educational content for the campus via FTTx and LAN, to deploy the network at very low maintenance costs.
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IETF VoIP Protocols
• • • • SIP is used at the control plane and RTP/UDP is used for the voice transport• • • • H.323 was the first, and still is the most used, easy internet-working POTS & ISDN
(but it is getting less popular)• • • • SIP, used for IP phones, is currently popular, as it is very flexible• • • • SIP can be integrated easily with PCs, e-mail, web and corporate platforms
IP
UDPTCP
RTP
Audio VideoSDP PINT IMP
SIPN
etwork
Application
Transmission
Supplementary
Signalling Voice over IP
Services
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Voice over IP Network
IP is data-oriented, but can also support multiple applications based on voice and video.
Why VoIP?• • • • Subscribers: cheaper calls, integration with PCs and e-mail• • • • Carriers: convergence across a unique network• • • • Service providers: new business opportunity• • • • Manufactures: new market demands
VoIP uses known protocols such as:• • • • IP, TCP, UDP (User Datagram Protocol)• • • • RTP (Real Time Protocol), RTCP (Real-Time Control Protocol)• • • • SIP (Session Initiation Protocol), H.323 (ITU-T)
Hi!
IP Network
PSTN
PABXVoIP Router Router
Gateway
VPN
VoIP
Voice Codec Framing Protocols
Codec
Transcoding
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Voice Codecs
• • • • Waveform codecs: PCM, ADPCM, CVSD• • • • Vocoders (synthetic voice): LPC• • • • Hybrids (waveform with synthesizer): CELP, ACELP, RPE-LTP, VSELP
1 2 4 8 16 24 32 40 64
1
2
3
4
5MOS
CS-ACELP 8(G.729)
LD-CELP 16(G.728)
ADPCM
PCMVOCODERS
CELP
ADPCM 24(G.726)
ADPCM 16(G.726)
PCM(G.711)
ADPCM 32(G.726)
LPC 4.8
kbit/s
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SIP Protocol
SIP is the protocol used to establish IP sessions between users, to set up VoIP calls, as well as multimedia conferences, multimedia distributions or multicast sessions. However, this protocol does not transport voice or multimedia contents.
IP
SIP Proxy
Caller
Domain A Domain B
Router Router
Recipient
sip.caribean.comSIP Proxy
sip.trendcomms.com
SIP Signalling
VoiceINVITE
SIP Request(simplified trace)INVITE sip: [email protected] SIP/2.0Via: SIP/2.0/UDP mkt12.caribean.com;To: pepon <sip:[email protected]>From: Alice <sip:[email protected]>;Contact: <sip:[email protected]>Content-Length: 142
SIP Response(simplified trace)SIP/2.0 200 OKVia: SIP/2.0/UDP mkt12.caribean.comTo: pepon <sip:[email protected]>;From: leila <sip:[email protected]>;CSeq: 314159 INVITEContent-Length: 131
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Typical SIP SessionSIP protocol (IETF RFC 3261).
What it covers:• • • • User search• • • • Call Init, Control and Close • • • • IP address, UDP/TCP • • • • Changes during the session• • • • Supplementary services
What it doesn’t cover:• • • • Type of network to be used• • • • Type of codecs to be used• • • • Session details (formats,
codecs...)• • • • Where and how the proxy,
registers, redirections etc. are implemented
Note that the caller does not send the Invite message directly to the recipient, but to an SIP proxy that locates the user and starts negotiating the session parameters.
SIP Proxy
Caller Recipient
Router Router
Invite
TryingInvite
InviteTryingRinging
RingingRinging OK
OKOK
ACK
VoIP session
Bye
OK
sip.ideal.com SIP Proxysip.trendcomms.com
IP Network
SIP
SIP
VoIP
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Internet-Working with PSTN/ISDN
Done by means of gateways.• • • • Gateways translate the voice
between the IP and the PSTN network.
• • • • Signalling, SIP to/from SS#7, has to be translated as well.
• • • • Translated messages (often only approximations to the original).
There are two types of gateways:
1. Media Gateways (MGs) convert data from the format required by a circuit-switched network to that required by a packet-switched network.
2. Media Gateway Controllers (MGCs) to handle all tasks related to call control and signalling.
VoIP
IP Phone Proxy
Gateways
PTSN / ISDN
Invite
InviteTrying
IAM
ACM
Trying
ANM
Session ProgressSession Progress
One-way RTP
OK
OK
ACK
ACK
communicationsOne-way Circuit
Two-way RTPCommunications Two-way Circuit
Legacy
Ringing tone
Hello?
Two-way Circuit
PCM
SwitchVoice
SIP ISUP
IP Network
SignallingSignalling
Voice
MG
MGC
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RTP and RTCP Basics
Encoder
RTP
VoiceDecoder
Voice stream Packets ^ timestamps Packets with jitter
Retimed stream
IP
Clock Clock
RTP Voice stream
Hellooo!
Report ReportRRSR RTCP
Real Time Protocol (RTP) RFC 3550• • • • Used to transport voice and video signals
in real time• • • • Congestion produces jitter at the far end• • • • RTP inserts a timestamp in all voice packets • • • • Timestamps are used to ensure that all voice
packets that are delivered to the far end maintain the time that was originally generated.
Note that RTP does not provide QoS, but just transports timing signals.
Real-Time Control Protocol (RTCP)
RTCP complements the RTP protocol with information on the QoS received: delays, loss, jitter, etc. It provides:• • • • persistent session information• • • • basic session management• • • • performance feedback to communication
parties of intermediate probes
TriplePlay Rollout/Maintenance
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Delivering QoS water (yes!)
The problem of delivering QoS in packet networks can be compared with water distribution.• • • • In the diagram, two pumps supply water for two towns, Town A and Town Z.• • • • Some water is lost in the pipelines between the pumps and the towns.
Some water is lost
Town Z
Town A
Waster pumps
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Delivering QoS: Heavy Load
The water company now needs to deliver water to a third town, Town M.• • • • A new pump could theoretically supply water for Town M.• • • • As more water is pumped in the pipelines, more water is lost before it reaches its destination.• • • • The result is that now Town M can get the water it needs, but there is not enough water for Town Z.
Even more water is lost
Water supply to Town Zis compromised
Town A Town M
Over-provisioning
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Delivering QoS: Over-Provisioning
• • • • The water company solves the problem by installing a fourth pump.• • • • Now much more water is lost in the pipelines, but all three towns can receive the water they need.• • • • The ratio between water pumps and serviced towns is now 1.33 pumps / town.• • • • What would happen if it were necessary to deliver water to a fourth town?
Town A Town M
Over-provisioning
An extra pump is added
Much more water is lost
At least, the water supply cannow be guaranteed to town Z
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Delivering QoS: Fixing the Network
• • • • There is an alternative to over-provisioning: fixing the distribution pipelines.• • • • Fixing the network can be more expensive than over-provisioning.• • • • The ratio between water pumps and serviced towns is now 0.66 pumps / town.
Town A Town MPipelines are fixed
No more water is lost
Two pumps only
Town Z
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Triple Play Testing
Triple Play is an application that runs over a large stack of telecom/datacom protocols. This means that bad quality of service or loss of service can be caused by many different factors:• • • • CPE faults• • • • Access faults, depending on the technology used• • • • IP networks must support proper QoS and multicast requirements• • • • Service availability and performance
SDH NGIP NetworkGateway
IPTV Servers
TelephonesProxy
Internet Internet
CPE Access ServiceIP Network- Configurations- Wiring- Hardware/Software
- xDSL/cable/fibre faults- Bit rate expectations- Security/Privacy
- Packet loss, Delays- QoS management
- IP continuity- Service availability
- Core infrastructures - Contention- Multicast - Performance- Data Performance
- Voice/Video quality- DSLAM performance
ModemSTB
VoIP
Data
DSLAM
Cable
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Troubleshooting ADS2+ and VDSL
DSL service providers can choose between two possible configurations for the local loop:• • • • Fixed data rate: The transmission bandwidth between the customer premises and the CO is fixed.
The transmission performance (SNR and noise margin) may change. It must be checked that the upstream and downstream rates match the configured values.
• • • • Fixed SNR: The local loop performance (SNR and noise margin) is fixed. Transmission rates may differ for each customer. It must be checked that the noise margin is 6 dB or better.
Tester DSLAMUpstream
Downstream
Broken ormisconfigured
equipment
CrosstalkNoise
Faultylines 1.5 3.0 4.5 6.0
Reach
1
10
100
Dow
nstre
am b
it ra
te
VDSL2VDSL
ADSL2+
ADSL2
ADSL
Mbit/s
km
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Troubleshooting Optical Access
DSL service providers can choose between two possible configurations for the local loop:• • • • Optical TDR: check the physical conditions of the fiber, including continuity.• • • • Optical characterization: evaluate attenuation and absolute power level during transmission.• • • • Bandwidth: PONs use a multipoint-to-point topology; the more subscribers there are,
the more critical the system is.• • • • Efficiency: The PON is a shared medium; the scheduling performance must be checked.• • • • Security: Downstream signals are encrypted for all subscribers, to guarantee privacy.
Tester
Splitter
Fibre
ONU
Fibre
PON
OLTSubscribers
Tester
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Determining Up/Down Bit Rates
• • • • During synchronization and training the modem and the DSLAM agree the upstream/downstream bit rates in the local loop.
• • • • The actual transmission rates can be smaller due to congestion in the network or in the remote system.• • • • The bit rate that the FTP client or server can send or receive depends on the local loop, the
transmission conditions of the whole network and the path between the client and the server.
PUT GET
FTPServer
TesterNoiseCrosstalk
Congestion
QoSissues
Congestion
IP
QoSissues
MAN
Access NetworkIssues
Transport NetworkIssues
Server SideIssues
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Layer-3 Continuity
In the case of service failure, the following should be tested:• • • • Physical layer continuity
- Copper pair- Fibre optics- Coaxial cable
• • • • DSL synchronization• • • • IP Ping continuity• • • • Trace Route delays
IP ping Trace Route
address, timeaddress, time address, time
SDH NGIP Network
Internet InternetModem
Data
Data Servers
CPE Access ServiceIP Network
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Internet Access Test
The typical data applications (generally Internet-based) that need to be to checked are:• • • • Web browsing performance; a basic facility for residential customers• • • • FTP capacity for file uploading and downloading• • • • Traffic statistics compiled during data browsing• • • • PPP authentication
SDH NGIP Network
Internet InternetModem
Data
Data Servers
CPE Access ServiceIP Network
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IPTV: The Subscriber’s Point of View
The QoE test aims is to measure how good the service is from the customer’s point of view. In practice it is a combination of packet impairments and video content measurements.
Quality of Service (QoS) Quality of Experience (QoE)
Content Quality- PCR Jitter- Coding distortion- Server overload
Video: Blocking, blurring, visual noise, loss of colour, edge distortion, pixelization, audio/video sync...
Transport Quality- Packet loss- Latency and delay variation- TCP Retransmissions
Voice: Distortion, noise, echo, loss of interactivity, interruptions, accessibility...
Transaction Quality - IGMP latency (IPTV)- RTSP latency (VoD)
Data: Low speed, low interactivity, wrong formatting, authentication problems...
AudioVideo
DataAudio
Contribution
IP NetworkSTB
Packet LossSync error
Packet DelayPacket Delay
Continuity errorPCR Jitter
Transport error
Packet Jitter
QoS parameters User Experience QoE measurement
Coding error
- Pixelation- Freezing- Lip Sync- Blurring- Distortion- Zapping Delay
- Pixelation- Freezing- Lip Sync- Blurring- Distortion- Zapping Delay
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Verify the IPTV Service
Video rendering is important for qualitative video performance assessment.
A single lost packet in an MPEG-2 video stream is displayed as several errored pixels or even lines in• • • • a video frame (spacial error propagation), • • • • several video frames with errored pixels (temporal error propagation).
Temporal error propagation
Spatial error propagation
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Testing points
The video preview test can be performed from different points in the customer premises or in the local exchange:• • • • The WAN connection is used to test the service provider network, but not the subscriber network.• • • • The LAN connection is useful to test the combined performance of the subscriber network and the
service provider network.• • • • The LAN Connection can be used to diagnose problems in the modem/router in the customer
premises due to firewalls, NAT, and unicast or multicast routing.
WANLAN
Modem/RouterSTBTV
Tester Tester
IP Network
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Video IGMP Delay
How to check the video IGMP delay:• • • • Channel zap, checks the delay in receiving the image when the channel is changed.• • • • Transmission: TV channels are transmitted in IP networks by using multicast IP datagram flows.• • • • Joining/Leaving an IP multicast group is managed by the Internet Group Management Protocol
(IGMP). Joining/leaving multicast groups may take time. The user sees this as excessive delays and degraded service.
Join
TesterMulticast
Local loop
Join request
Join reply
Leave request
Leave reply
Leav
e
Contentsservers
agent
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Testing SIP Across a NAT Firewall
Problems with NAT arise, because with SIP, there is some addressing information that is carried in the application payload. This information is bypassed by devices that only work at layer 3.• • • • SIP responses may fail to find the way back to the originator of the transaction if the “Via” or “Contact”
fields of the SIP requests cannot be resolved to a public IP address.• • • • The media transport protocol, usually RTP, may fail to find the participants of a session if they are
behind a NAT router.
NAT firewall
Untrusted networkProxy
UDP SIP request
Trusted networkUser agent
Port opened: 5650
DST Port: 5060
Port closed, drop packet
UDP SIP response
LAN Internet
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Opinion Models (in-service test)
MOS (Mean Opinion Score): To arrive at an MOS score, a tester assembles a panel of “expert listeners” who rate the quality of speech samples that have been processed by the system under test. • • • • Ideally, a panel would consist of a mix of male and female listeners of various ages• • • • The samples should reflect a range of typical voice conversations• • • • Each panelist rates the quality of the system output from 1 to 5, with 1 indicating the worse and 5 the best• • • • The scores of the panelists are then averaged
E-Model: a computational model that uses transmission parameters (errors, packet loss, delay, echo...) to predict the subjective quality of voice. Good for conversational MOS evaluation using R-factor.
R-factor100
9490
80
70
60
50
User SatisfactionMOS
0
4.54.44.3
4.0
3.6
3.1
2.6
1
Very satisfied
Satisfied
Some users dissatisfiedMany users dissatisfied
Nearly all users dissatisfied
Not recommended
Desirable
Acceptable
Unacceptablefor toll quality
Distribution Network
VoIP Router Router VoIP
Conversational MOS evaluation (Bidirectional)
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Speech Layer Models (out-of-service test)
PSQM (Perceptual Speech Quality Measure), defined by ITU-T P.861, uses pre-recorded voice signals that are transmitted at the origin and compared at reception in the 300 - 3 400 Hz frequency range. Created to evaluate codec performance, basically the distortion of the voice signal. PSQM is not designed to reflect the effects of packet loss or jitter.
PAMS (Perceptual Analysis Measurement System) also compares an output signal with the input signal, but using a different algorithm based on factors of human perception to measure voice quality, scoring on a 1 to 5 scale that can be correlated to MOS.
PESQ (Perceptual Evaluation of Speech Quality), developed based upon PAMS and an improved version of PSQM called PSQM+. Uses the best features of both: the robust time-alignment techniques of PAMS with the accurate modelling of PSQM. It targets not only VoIP, but also ISDN, GSM and POTS.
Distribution Network
PABXVoIP
Router Router
VoIP
Listening MOS evaluation (Unidirectional)
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VoIP Delays
Rec. ITU-T G.114, unidirectional delay in ms:• • • • 0 - 150: acceptable for most applications• • • • 150 - 400: acceptable, but degrades the QoS• • • • > 400: unacceptable; only for voice messages or walkie-talkie gadgets
IP
Hellooo!
Encoding Buffering Ingress
Transmission
Egress Jitter buffer Decoding
Half DuplexITU Internet, Satellite
0 100 200 300 400 500 600 700 800 900
ms
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Summary
1. In lightly loaded packet networks, delay, delay variation and packet loss ratio can be kept relatively under control. However, under higher traffic loads, carriers must face a dilemma: increase the capacity of their networks further or implement QoS policies.
2. MPLS is perhaps the best QoS solution among the currently available options, including IntServ and DiffServ. It combines the features of Intserv and Diffserv with other features that are very much appreciated by carriers: Connection oriented technology, traffic engineering, carrier-class protection...
3. Providers must offer differential QoS both on a per customer basis and on a per service basis. Every service has its own QoS needs. Providing QoS on a per service basis is not just a problem of prioritization. The network must be prepared to fulfill the needs of every application.
4. QoS tests are performed as end-to-end measurements. For example, a tester can be used to measure delay, delay variation and packet loss, for several services/subscribers, from the customer premises.
5. Residential subscribers experience service deficiency rather than abstract QoS problems; because they buy services rather than transmission facilities. This makes QoE testing an important requirement of test equipment in residential applications.
Acronym ListACELP: Algebraic CELPADPCM: Adaptive Differential PCMADM: Add/Drop MultiplexerADSL: Asynchronous Digital Subscriber LineADSL2+: ultra-high-speed ADSLAPON: ATM PONARPU: Average Revenue Per UserB-Frame: Bidirectional Prediction FrameBPON: Broadband PONCAT: Conditional Access TableCELP: Code Excited Linear PredictionCPE: Customer Premises EquipmentCVSD: Continuously Variable Slope DeltaDiffServ: Differentiated ServicesDOCSIS: Data Over Cable Service Interface SpecificationDSCP: Differentiated Services Code PointDSLAM: Digital Subscriber Line Access MultiplexerDTT: Digital Terrestrial TelevisionDVB: Digital Video BroadcastDWDM: Dense WDMEPON: Ethernet PONES: Elementary StreamESCON: Enterprise Systems ConnectionEVC: Ethernet Virtual Connection EVPL: Ethernet Virtual Private Line EVPLAN: Ethernet Virtual Private LANFR: Frame RelayFTTB: Fibre To The BuildingFTTC: Fibre To The CurbFTTH: Fibre To The HomeFTTN: Fibre To The NetworkFTTP: Fibre To The PremisesGEM: G-PON Encapsulation ModeGFP: Generic Framing ProtocolGPRS: General Packet Radio ServiceGPON: Gigabit PONGSM: Global System for Mobile communicationHDTV: High Definition TVHFC: Hybrid Fibre/Coaxial network HSDPA: High Speed Downlink Packet AccessI-Frames: Intra Frame
IGMP: Internet Group Membership ProtocolIntServ: Integrated ServicesIPTV: IP TelevisionISP: Internet Service ProviderISUP: ISDN User PartLAN: Local Area NetworkLCAS: Link Capacity Adjustment SchemeLLC: Logical Link ControlLPC: Linear Predictive CodingLSP: Label-Switched PathLSR: Label-Switched RouterMAC: Media Access LayerMGC: Media Gateway Controllers MGCP: Media Gateway Control ProtocolMOS: Mean Opinion SquareMPEG: Moving Picture Experts GroupMPLS: Multiprotocol Label SwitchingMSPP: MultiService Provisioning PlatformMSTP: MultiService Transport PlatformMSSP: MultiService Switching PlatformNAT: Network Address TableNG SDH: Next-Generation SDHNGN: Next-Generation NetworkNIT: Network Information TableOAM: Operation Administration and MaintenanceOLT: Optical Line TerminationONU: Optical Network UnitOSPF: Open Shortest Path FirstOTN: Optical Transport NetworkP-Frame: Prediction FramePAMS: Perceptual Analysis Measurement SystemPCM: Pulse Code ModulationPCR: Program Clock ReferencePES: Packetized Elementary StreamPESQ: Perceptual Evaluation of Speech QualityPHB: Per Hop BehaviorPMT: Programme Map TablePPP: Point to Point ProtocolPON: Passive Optical NetworkPON: Private Optical NetworkPSTN: Public Switched Telephone Network
PSQM: Perceptual Speech Quality MeasurePOTS: Plain Old Telephone SystemPWE3: PseudoWire edge-to-edge EmulationQoE: Quality of ExperienceQoS: Quality of ServiceR-Factor: 0 to 100 ratio for voice quality (ITU G.107)RPE-LTP: Regular Pulse Excitation - Long Term PredictionRSVP: Resource Reservation ProtocolRTCP: Real Time Control ProtocolRTP: Real Time ProtocolSAN: Storage Area Network SDH: Synchronous Digital NetworkSDTV: Standard Definition TVSLA: Service Level AgreementSNT: Signal to Noise RatioSIP: Simple Internet ProtocolSMS: Short Message ServiceSTB: Set Top BoxSTUN: Simple Traversal of UDP through NATPAT: Programme Association TableTP: Transport PacketsTS: Transport StreamTSTV: Time Shift TelevisionUTP: Unshielded Twisted Pair cableVC: Virtual ConcatenationVPN: Virtual Private NetworkVDSL: Very High Bit rate DSLVLAN: Virtual LANVPLS: Virtual Private LAN Service VPWS: Virtual Private Wire ServiceVoD: Video On DemandVoIP: Voice over Internet ProtocolVSELP: Vector-Sum Excited Linear PredictionWDM: Wave-Division MultiplexingWiFi: Wireless FidelityWiMAX: World-wide Inter operability for Microwave AccessWIS: WAN Interface SublayerWLAN: Wireless Local Area NetworkWM: Windows Media
That’s all, thanks