ITU-T Workshop on
Bridging the Standardization Gap
and Interactive Training Session
(Cyberjaya, Malaysia, 29 June – 1 July 2010 )
Implementation of IPTV
Content Delivery network
and NG-CD Technology
Yeong-il Seo,
Director
KT Network R&D Lab
Cyberjaya, Malaysia, 29 June – 1 July 2010
Contents
IPTV Content Delivery model
Multicast deployment issues for IPTV
Multicast VPN for IPTV
P2P as Content Delivery technology
P4P introduction as NG-CD
Cyberjaya, Malaysia, 29 June – 1 July 2010
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IPTV Content Delivery model
IPTV Content
Delivery Model
Main: real time broadcast
Main : VoD
Real time broadcast channel
channel service
Native IP Multicast
model
• High Available, QoS guaranteed,
Secure, Stable IPTV multicast
network
+ VoD
Alternative Multicast
(Unicast) model
• Server based
• CDN based
• P2P based
Hybrid Model
• Native IP multicast + Alternative
multicast
• Overlay multicast
+
+
Next Generation Content
Delivery Model ?
Cyberjaya, Malaysia, 29 June – 1 July 2010
3
IPTV CD network architecture
APT
CO
VoD
(Hot source)
HE
router
VoD
IPTV
Edge
Small Aggregation SW
(L3)
internet
Customer side
IGMPv2
Big aggregation
switch
Advanced
IP BB
mcast
access
HE
router
BB
IX, overseas, IDC
IPTV
HeadEnd Center
HeadEnd
MSDP
PIM-SM
layer
features
HE center/
ㅇ Bi-directional IPTV service, PPV service, Data broadcast service, VOD service, T-Internet/
T-Communication service
VoD server farm
BB
(IP Premium)
ㅇ Guarantee of Real time broadcast service stability : QoS guarantee, HA for Multicast
network, Stable multicast routing, OAM, Multicast Security
Access
ㅇ IP address assignment and authentication
(aggregation SW) ㅇ Multicast features & QoS enabled
Small L3
STB
ㅇ Last mile device for PIM-SM/IGMP, QoS enabled
ㅇIPTV data decoding, IGMP, VoD(D&P or Streaming), SD/HD, H.264/MPEG2/WMT
Cyberjaya, Malaysia, 29 June – 1 July 2010
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IPTV CD network requirement for implementation
Advanced IP network technology in converged IP network
High Quality TPS, especially PSTN emulation service over IP
High Quality IPTV service with stable IP multicast technology
Wibro service
Multicast VPN, Managed VPN, Managed L/L for enterprise
customer
Which advanced IP network technology are needed ?
Cyberjaya, Malaysia, 29 June – 1 July 2010
One Network, Multi Services!
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IPTV CD network deployment issue
Design considerations for IPTV multicast
Address
High availability
QoS
Security
Multicast Topology
Multicast Addressing issues
IANA allocation of class D address
http://www.iana.org/assignments/multicast-addresses
For interoperable multicast channels, Should use ‘GLOP’
address.
Globally routed private address : 233/8
How to use? : 233.16bit official AS #.0/24
Ex) KORNET Case (AS number 4766) : 233.18.158.0/24, Other AS
number 5662 case : 233.22.30.0/24
Site-local address : 239/8
Cyberjaya, Malaysia, 29 June – 1 July 2010
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Design considerations for IPTV multicast : HA
Other Unknown
Why HA ?
Link Failure
Time to Recover from
Layer1 failure
 Congestion

9%
36%
32%
Congestion:
5%
Router Operations
Software Upgrade
 Hardware Upgrade
 Configuration Errors

23%
Router Failures
Software failures
Hardware failures
 DOS Attacks

Which HA features?

* Source: University of Michigan
Multicast Traffic ready condition for whole PIM links
The Use of Static IGMP Join, No service interruption from Link/Node
failure
No service interruption from PIM neighbor cutoff
Fully redundant system architecture & topology
Robust network against Any DoS attacks
ISSU
QoS : Perfect provisioning, Diffserv for IPTV traffic and monitoring
Cyberjaya, Malaysia, 29 June – 1 July 2010
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Design considerations for IPTV multicast : Security
Multicast security
Critical issue for multicast network
RP security
RP : Group range filtering
For example, except approved GLOP address for KT IPTV service (:
233.18.158.0/24), whole other group range should be filtered in RP.
PIM register message filtering : only approved source can register to RP
MSDP SA filter : Limitation for SA information per MDSP peer, per source,
per instance
PIM router security
Multicast Route limit
To protect network against any kind of Worm attack via multicast routing update
BSR message filtering
PIM authentication among each neighbors
TCP/ICMP message filtering for 224/4
Because only UDP traffic around 224/4 is used for IPTV service
Last mile PIM router
Filtering all multicast traffic except approved IGMP join messages
; Protection against multicast source spoofing
Cyberjaya, Malaysia, 29 June – 1 July 2010
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Design considerations for IPTV multicast : Topology
Multicast Topology
Optimal RP positioning ?
RP position vs. Multicast traffic delay ?
RP position vs. Multicast Stability ?
Loop free, Delay/Jitter independent, stability guarantee topology
Optimal position to exchange SA information amongst multicast service provider
Tree topology case like KT, Best test result : HE=RP
Optimal RP redundancy ?
Dynamic RP vs. Anycast RP
Multicast Traffic Load balancing issue
Based on source IP, channels
APT
CO
VoD
(Hot source)
HE router
VoD
IPTV
Edge
internet
Small Aggregation
SW (L3)
Customer side
Cyberjaya, Malaysia, 29 June – 1 July 2010
IGMPv2
Big aggregation
switch
access
PIM-SM
IX, overseas, IDC
Advanced
IP BB
HE router
IPTV
HeadEnd Center
mcast
BB
HeadEnd
MSDP
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Multicast VPN for IPTV & case study
 With multicast VPN
 Bidirectional e-learning/internal broadcasting service for VPN customer
 Customized Advertisement service for Bank/Hospital/Gas station/Fastfood chain store/Department store/Government agency etc.
 MPLS L3VPN case
CE
MPLS L3 VPN
(Premium BB)
 Usually, Metro Ethernet, TDM access line
 MPLS Label binding for multicast traffic is
Not available.
CE
mVPN
고객지사
Cyberjaya, Malaysia, 29 June – 1 July 2010
GR
ET
unn
el
VPN A
 Also, IPSec cannot handle multicast
traffic.
 GRE over IPSec  Multicast over IPSec VPN
CE
* MDT : Multicast Distribution tree
 Usually, xDSL access line
 With GRE, multicast traffic can be
transmitted through each IPSec tunnel.
Per VRF
MDT
VPE
VPE
 With GRE, multicast traffic can be
transmitted through each VRF’s MDT.
 X4Biz(IPSec VPN) case
VPE
mVPN
고객본사
MPLS VRF
Internet
IPSec VPE
Aggregator
일반
X4Biz지사
PE
Per VRF
MDT
VPE
MPLS
L3 VPN
* VPE : VPN Edge router
* PE : Premium Edge router
mVPN
고객지사
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P2P Trends as Content Delivery
Explosive increase of P2P traffic in ISP BB
Good technology, but not so good impact on modern society
Infringement of copyright : Free sharing of music & movie titles
With P2P, Kids can easily access to pornographic/violent movies.
P2P must be a major menace to Telco
Explosive increase of P2P traffic force ISP’s CAPEX/OPEX increase.
P2P based IPTV, SoIP, CDN
Cyberjaya, Malaysia, 29 June – 1 July 2010
User %
Traffic rate
1%
27%
5%
49%
10%
63%
20%
80%
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Why Heavy User traffic increase ?
 Why Heavy User traffic increase ? : Multi-flow unfairness issue
 TCP fairness issue : In current IP network, Same Bandwidth per each TCP flow
 Each flow’s BW= 1/total flow
 By exploiting ‘TCP fairness issue’, such as P2P application,
 Host, who is using P2P application, can generate bulk TCP flows and can monopolize bandwidth usage
in some specific congested link.
 Lifetime of P2P session is maintained until each file transfer is complete (minutes~hours), it can make
normal users slowdown
Host A
100 Mbps shared Link
100 Mbps shared Link
HTTP, FTP
e-mail
Host A
P2P
HTTP
Host B
HTTP
Host B
 P2P over UDP case
 UDP traffic injection in congested link  TCP traffic : more serious performance degradation
 More serious concern, a matter of time, go on increasing
 Related article : http://www.theregister.co.uk/2008/12/01/richard_bennett_utorrent_udp/
“BitTorrent declares war on VoIP, gamers!”
Gamers, VoIP and video conference users beware. The leading BitTorrent software authors have
declared war on you ~~~~~~~the developers of the uTorrent P2P application have decided to make
the UDP protocol the default transport protocol for file transfers.
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Cyberjaya, Malaysia, 29 June – 1 July 2010
Impact & Menace of P2P technology as CD
on Telco’s business
Low-cost P2P based CDN solution
Low price broadband subscriber line with P2P CDN solution
Sales Loss of Telco IDC
Big Menace to Telco’s TPS
P2P based free/low cost SoIP solution, P2P over Wifi/Wibro/LTE
Emergence of P2P based low cost/free VoIP solution such as
Skype(out)
Collapse of PSTN overseas call market, menace to Telco SoIP
market
P2P based low cost VoIP solution over wireless/mobile internet
access  menace to cellular communication market
Wifi Direct, Wifi P2P  direct P2P communication amongst Wifi terminal
which has AP capability
P2P based IPTV
In CAPEX/OPEX perspective, by using of P2P based IPTV solution,
Portal/OTT can have ‘cost competitive advantage’ comparing with Telco
case.
Easy free riding of Telco network, not necessary to deploy total IPTV network/server
Cyberjaya, Malaysia, 29 June – 1 July 2010
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cf. P2P based content delivery solution
Cyberjaya, Malaysia, 29 June – 1 July 2010
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P4P introduction as NG-CD
P4P (Proactive network Provider Participation for P2P)
Definition : Framework for ISP and P2P application to collaborate for the
optimization of peer-to-peer connections
Why P4P ?
“Close & Optimal” peer selection for the performance increase of P2P
application
With P2P traffic localization, increase of ISP’s network efficiency and save
of ISP CAPEX/OPEX
Traditional CDN
P2P
P2P with P4P
Internet Transit
Regional Routers
Edge Network
More Viewers =
Worse performance
Higher cost
Cyberjaya, Malaysia, 29 June – 1 July 2010
More Viewers =
Better performance
Lower cost
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P4P introduction as NG-CD
P4P component
iTracker (ISP Portal Service)
From ISP’s Network information
 iTacker is providing ‘optimal path and
topology information’ to pTracker
pTracker (Application Tracker, AppTracker)
Interworking with iTracker,
pTracker is providing ‘optimal peer information’
to each P2P application
Case study
Comcast case (draft-livingood-woundy-p4p-experiences-02)
Application download performance increase
Overall P2P download performance : 15% increase
Comcast internal P2P download performance : 50% ~ 80% increase
P2P traffic localization effect
Upload traffic : 34% decrease
Download traffic : 80% decrease
Cyberjaya, Malaysia, 29 June – 1 July 2010
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IETF trend for NG-CD
ALTO information export service
P2P application service delivery optimization
Application Level Traffic Optimization
P4P:Provider Portal for P2P Applications)
P2P traffic localization effect
Application download performance increase
NG-CD based on Routing Proximity
Best path for content routing by using of ISP network information
Routing info, BW info, Performance info from RTT/one-way delay
Cyberjaya, Malaysia, 29 June – 1 July 2010
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Q&A
Q&A
How to contact speaker?
Tel : +82-42-870-8333
E-mail : syi1@kt.com
Skype ID : syi101
Cyberjaya, Malaysia, 29 June – 1 July 2010
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