multiservice edge architectures and solutions for service
Post on 03-Feb-2022
0 Views
Preview:
TRANSCRIPT
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
1
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 1BRKAGG-200114557_04_2008_c1
© 2008 Cisco Systems, Inc. All rights reserved. Cisco PublicBRKAGG-200114557_04_2008_c1 2
Multiservice Edge Architectures and Solutions for Service Providers
BRKAGG-2001
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
2
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 3BRKAGG-200114557_04_2008_c1
Abstract
This session presents design options for centralized and distributed multiservice broadband network architectures that scale to tens of millions of subscribers and bandwidths up to 100 Mbps per household. The session introduces popular triple-play broadband aggregation architectures. The advantages and disadvantages of the different architectures in terms of bandwidth scalability, policy plane scalability, failure radius, traffic patterns, service flexibility, and more is then discussed. Attendees learn to identify the architectural trade-offs between centralized and distributed broadband architectures, and which criteria should be used in an architectural evaluation.
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 4BRKAGG-200114557_04_2008_c1
Agenda
The Evolution of Multimedia Services
Broadband Architecture Models
Architectural Comparison
Sample NGN Broadband Architectures
Summary
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
3
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 5BRKAGG-200114557_04_2008_c1
The Evolution of Multimedia Services
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 6BRKAGG-200114557_04_2008_c1
Understanding Where Broadband Started Reasons the BRAS Began Centralized
Initially sparse customer take rates
Faster Roll-out in coverage
Subnetting & IP address pool utilization
Reuse of SDH infrastructure
Internet Access “Star Aggregation” traffic dominance
Similar to centralized Dial paradigm
Conservative growth assumptions
Availability of IP Operations Expertise WhichStill
Apply?
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
4
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 7BRKAGG-200114557_04_2008_c1
Massively distributedSelf-service / instant ITDesktop Virtualization
Instant business“Office of One”Profitable interactions
Grassroots innovationPersonalizationConsumer within
Virtualized, SecureReal-time
Information
Borderless Enterprise
EmpoweredUser
Customers Are Transforming…
THE NETWORK IS THE PLATFORMCOLLABORATION, WEB 2.0, PRODUCTIVITY
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 8BRKAGG-200114557_04_2008_c1
Service Transformations
Web 2.0 – the network as the platform
Empowered UsersPersonalization
Virtualized, secure, real-time informationMassively distributed
Self-service / instant IT
Desktop Virtualization
Borderless EnterpriseInstant business
“Office of One”
Profitable interactions
Service Provider Implications1. Enable ubiquitous high bandwidth, quad-play services
2. Increase speed to integrated, scalable services
3. Move up the value stack with the customer
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
5
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 9BRKAGG-200114557_04_2008_c1
NTT Next-Generation ServicesResidential
Home EntertainmentDigital Terrestrial TV over IPHD IPTVHD VideoHigh-quality audio distribution
High-Definition VideophoneOne phone (FMC)Home & Security control
Kids-safety, supervisory robots
BusinessConferencing
TV Conferencing (incl. Multipoint Web)Wideband IP Conference Phones
Seamless CommunicationHD Interactive Video, Web collaboration
Advance telecommuting, push-to-talk-multimedia
Nursing & Medical care servicesTelepathology, Medical information sharing
Public ServicesDisaster information, earthquake early warning, Safety information sharing
Highly secure Network Services
http://www.ntt.co.jp/ir/library_e/nttis/2007spr/note.html
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 10BRKAGG-200114557_04_2008_c1
Service Innovation Is Key to Incremental Revenue Generation
PSTNPSTN
… … …
OA&MOA&M
CPE
Voice apps
Enterprise data
Consumer data
Frame relay/ ATM
Frame relay/ ATM
Internet access
Internet access
OA&MOA&M OA&MOA&M
Existing service delivery approach
CostlySlow to market
IntegratedOne-size-fits-all
3rd party applications
Network services / Intelligent IP infrastructure
Network services / Intelligent IP infrastructure
… … …
OA&MOA&M
Open service deliveryOpen service deliveryCPE
NGSPapps
ASP Content
NGSP destination
EfficientRapid response
OpenPersonalized
Open service deliveryfor faster innovation
& competitivedifferentiation
Flexible business models to matchservice lifecycle
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
6
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 11BRKAGG-200114557_04_2008_c1
Telecom Italia (42€)
VoD w/ 25000 titlesSKY TV, Exclusive MTV, 100 TV channelsEPGUp to 20Mbps Flat rate InternetVoice with SMSFree 2nd phone number (VoIP)WiFi Modem
23 TV channelsVoDFirewall & Security3Mbps downstream ADSL 20MB email storage50MB homepage
KPN (53€)
France Telecom
(35€)50 TV channels1000 VoDTime-controlSecondary phone with unlimited metropolitan callsVoice mailUp to 18Mbps / 800 Kbps internet5 email accounts Web page Parental control
Understanding Where Broadband Is GoingCurrent European SP Multimedia Service Offerings
It is time to revisit some operational assumptions…
Formuleinternet+TV+téléphone
Alice Home TV InternetPlusBellen Lite + Interactieve TV
Deutsche Telekom
(49€)VoD w/ 1700 titles70 TV channelsEPG, NW-VCR,Up to 16Mbps Flat rate InternetVoice with SMSFree 2nd phone number (VoIP)Hotspot flat rate
T-Home Entertain
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 12BRKAGG-200114557_04_2008_c1
Broadband Architecture Models
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
7
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 13BRKAGG-200114557_04_2008_c1
Definitions
Single-Edge vs. Multi-Edge ServicesSingle: all services destined to the same subscriber flow through one edge system, forming an integrated policy enforcement point
Multi: services destined to the same subscriber do not flow through one edge system.
Centralized vs. Distributed EdgeCentralized: Edge systems are concentrated in few IP PoPs and are connected to access nodes via an aggregation network.
Distributed: Edge systems are dispersed in many IP PoPs close to the subscribers and may even be co-located with the access nodes
Clustered vs. UnclusteredUnclustered: Allocating all subscribers for a particular service to one system
Clustered: Allocating the subscribers to a particular service over many systems located in the same PoP
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 14BRKAGG-200114557_04_2008_c1
Architectural Dimensions
DistributedCentralized
Single-Edge
Multi-EdgeClustered
Unclustered
Some services are produced on distributed devices, whereas other
services are produced centrally
All services flow through a single device, distributed in the architecture close to the
subscriberDistributed
Separate devices for various services. Could be service specific
edge, or common per-subscriber PEP but on multiple systems
All services flow through single device, located in a centralized PoPCentralized
Multi-EdgeSingle-EdgeServices
Geographic
x
y
z
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
8
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 15BRKAGG-200114557_04_2008_c1
Centralized Unclustered Single-Edge
CoreAccess Edge
DSL
Content Farms
VOD TV SIP
Mobile
ETTx
PON
MSPP
Cable
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
AggregationL2 / Simple L3
Aggregation NetworkMPLS/IP
Integrated Services
Core NetworkMPLS /IP
Residential
STB
Business
Corporate
Internet Voice VoD / TV Business
Residential
STB
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 16BRKAGG-200114557_04_2008_c1
Centralized Clustered Single-Edge
EdgeAggregationL2 / Simple L3
Aggregation NetworkMPLS/IP
Integrated Services
Core
Content Farms
VOD TV SIP
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
Access
DSL
Mobile
ETTx
PON
MSPP
Cable
Core NetworkMPLS /IP
Residential
STB
Residential
STB
Business
Corporate
Internet Voice VoD / TV Business
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
9
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 17BRKAGG-200114557_04_2008_c1
EdgeAggregationL2 / Simple L3
MSE
DPI
Aggregation NetworkMPLS/IP
BNG
Core
Core NetworkMPLS /IP
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
Content Farms
VOD TV SIP
Access
DSL
Residential
Mobile
ETTx
PON
MSPP
Cable
Residential
STB
Residential
STB
Business
Corporate
Internet Voice VoD / TV Business
Centralized Unclustered Multi-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 18BRKAGG-200114557_04_2008_c1
Centralized Clustered Multi-Edge
EdgeAggregationL2 / Simple L3
MSE
DPI
Aggregation NetworkMPLS/IP
BNG
Core
Core NetworkMPLS /IP
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
Content Farms
VOD TV SIP
Access
DSL
Mobile
ETTx
PON
MSPP
Cable
Residential
STB
Residential
STB
Business
Corporate
Internet Voice VoD / TV Business
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
10
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 19BRKAGG-200114557_04_2008_c1
Access
DSL
Mobile
ETTx
PON
MSPP
Cable
CoreEdgeContent Farms
VOD TV SIP
Core NetworkMPLS /IP
Integrated Service
Ethernet/MPLS/IP
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
Residential
STB
Residential
STB
Business
Corporate
Internet Voice VoD / TV Business
Distributed Unclustered Single-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 20BRKAGG-200114557_04_2008_c1
Distributed Unclustered Single-Edge
Access
DSL
Mobile
ETTx
PON
MSPP
Cable
CoreEdgeContent Farms
VOD TV SIP
Core NetworkMPLS /IP
Integrated Service
Ethernet/MPLS/IP
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
Residential
STB
Residential
STB
Business
Corporate
Internet Voice VoD / TV Business
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
11
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 21BRKAGG-200114557_04_2008_c1
Architectural Comparison
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 22BRKAGG-200114557_04_2008_c1
Architectural Comparisons
The different architectures can be evaluated against the following criteria
Capital Expenditures
Scalability (Bandwidth / Subscriber, Transport, Policy Control)
Operational Complexity (Troubleshooting, QoS)
Reuse of existing Operations procedures
Availability
Traffic Patterns
Economically serving areas of differing subscriber density
Service Flexibility
Operational Flexibility
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
12
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 23BRKAGG-200114557_04_2008_c1
Cost Optimization
Goal is to minimize overall Total Cost of Ownership (TCO) related to the deployment and operation of a broadband aggregation network delivering quad-play servicesMin Σ Capex(services, time) + Σ Opex(services, time)
s.t. Traffic flows <= Link CapacityTraffic flows <= Node capacityNode Capacities >= Number of subscribers….
Note: not just minimization of initial Capex at time t=0!Also minimization of Opex and expansion Capex
Assumes a timeframe tNeed to take subscriber and traffic growth into account
Network equipmentBNG, DSLAMs, PON…
Servers for each serviceSIP, RACS, RADIUS, Softswitches, Gateways…
Link CostsReal Estate
Capex Variables Opex VariablesPower: network, servers
SIP, RACS, RADIUS, Softswitches, Gateways…BNG, DSLAMs, PON…
Real estateLabour & Maintenance
OSS Changes, Cutover
Management Costs
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 24BRKAGG-200114557_04_2008_c1
Geographic Context for Overlaying Costs
Services with Local traffic needs (Video Caching, PSTN interconnect)
Availability / topology of Fiber
Areas of sparse subscriber density
Variety of mechanisms for failure recovery (IP, STP, RPR, RRR, WDM)
Availability / efficiency of Public IP subnetting
Size of BRAS failure domain
Speed/cost of BRAS failover
Flexibility to do area splits
Operations ability to manage local network elements
Broadband Aggregation StarAlternate paths not shown
C.O. data courtesy of:
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
13
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 25BRKAGG-200114557_04_2008_c1
Capital Expenditures (CapEx)
Argument around number and cost of devicesCentralized Multi-Edge architecture benefits from incumbency
Re-use of installed base, evolution of existing architecture
Pure L2 aggregation networks combined with centralized edge architectures seem to have cost advantages
BUT: how to handle multicast traffic in a pure L2 aggregation networkMotivate IP-enabled aggregation networks
Number of IP enabled devices in centralized and distributed architectures in same order of magnitude
Thus Capex in a similar rangeCapEx of distributed architecture comparable to centralized architecture with IP-enabled aggregation infrastructure
DistributedCentralized
?
Unclustered Single-EdgeClustered Multi-EdgeUnclustered
Multi-EdgeClustered Single-EdgeUnclusteredSingle-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 26BRKAGG-200114557_04_2008_c1
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
5000
1000
015
000
2000
025
000
3000
035
000
4000
045
000
5000
055
000
6000
0
Active Subscribers
Ban
dwid
th (G
bps)
0.9 Mbps / sub 10 Gbps Engine2.75 Mbps / sub 20 Gbps Engine5.1 Mbps / sub 160 Gbps Engine
Scalability—Bandwidth per Subscriber
Multimedia traffic impacts subscriber scalability per system
Bandwidth per subscriber increases from ~200 Kbps/sub for traditional Internet to 1-6Mbps/sub for multimedia servicesModels assume different service concurrency rates for Voice / Video / TV / Internet
Fixed-Mobile-Convergence place substantial additional scalability demands on systemsCentralized single-edge architectures reach scalability limitsClustered, multi-edge or distributed architectures offer better architectural scalability
Smaller number of subscribers per system
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
14
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 27BRKAGG-200114557_04_2008_c1
Scalability—Policy Control and Enforcement
Control plane functions are harder to architect than forwarding plane functions!Multi-edge requires multiple policy control messages to different network nodes Single-edge architectures benefit from single policy enforcement point
Policy enforcement communication efficienciesSingle authentication and authorization for all services at the policy enforcement pointMultiple services can be activated / de-activated in a single RADIUS CoA message with ISGBut: Centralized sing architecture needs to maintain a vast amount of state information per subscriber
Distributed Architecture benefits from Policy enforcement close to subscriber
No need to backhaul traffic that can be dropped
Distributed Single-Edge
Core
Per-subscriber
Multi-Edge
Aggregation MPLS/IP/Ethernet
Core
Per-subscriber per service
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 28BRKAGG-200114557_04_2008_c1
ETSI TiSPAN Architecture MappingFunctional Building Blocks
Edge
CoreAccessResidential
STB
Core NetworkMPLS /IP
RCEFAMF
NASS
Policy Control Plane (per subscriber)
Applications
User Equipment
TISPAN NGN CoreAccess network
RACS
DiameterH.248<tbd>
RACS
CLF
CNG RCEF
UAAFPDBFCNGCF
AMF
NACF
C-BGF I-BGF
I/S-CSCFP-CSCF
IBCF UPSF
TE
e3
e1
e2
a3
a4
a1
a2
e2
Re
Rqe4
Gq’Gq’
Gm
MwMx Mx Cx
IaIa
Sh
Isc
SPDF
A-RACFRr
Rd’
Service subsystems
IMS Core PSTN Emulation
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
15
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 29BRKAGG-200114557_04_2008_c1
TiSpan Building Blocks
TransportTE: Terminal EquipmentCNG: Customer Network GatewayAMF: Access Management FunctionRCEF: Resource Control Enforcement FunctionC-BGF: Core Border Gateway FunctionI-BGF: Interconnecting Border Gateway Function
Resource Admission Control Sub-system
A-RACF: Access Resource & Admission Control FunctionSPDF: Serving Policy Decision Function
Network Attachment Sub-systemCLF: Connectivity Session Location Repository FunctionCNGCF: Customer Network Gateway Control Function NACF: Network Address Configuration Function UAAF: User Authorization & Authentication Function
PDBF: Profile Database Function
Service SubsystemsP-CSCF: Proxy call session control functionI/S-CSCF: Interrogating / service call session control functionIBCF: Interconnecting Border Control FunctionUPSF: User Profile Serving Function
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 30BRKAGG-200114557_04_2008_c1
Scalability—System Resources
Amount of state information required can be substantial per BRASMemory
Chart shows per-session memory (function of QoS, HA, ISG)Configuration memory can be substantial (e.g. 7MB for 10000 triple-play subscribers)
Calls-per-second ratesAt 100 CPS, takes 10 minutes to set up 60000 sessionsIn addition to system boot time
Control Traffic BandwidthIP Address Allocation (e.g. DHCP)Session setup (e.g. PPP LCP, IPCP, PPPoE)Service setup (e.g SIP calls, ISG services)Min 12 messages and 300B per subscriber
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
0
200400
600800
10001200
14001600
1800
5000
1000
015
000
2000
025
000
3000
035
000
4000
045
000
5000
0
Number of sessions
Mem
ory
Req
uire
d (M
B)
No QoS QoS QoS w/ ISG
Memory for sessions onlyNot counting other configuration
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
16
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 31BRKAGG-200114557_04_2008_c1
Scalability—Transport
Centralized architectures rely on transport tunneling mechanisms in the aggregation network
VLAN / Tunnel scalability needs to be taken into accountMapping of VLANs to services: per-DSLAM VLANs, per-service VLANs, customer VLANs…
Tunnel scalability limits may be mitigated using clustering or multi-edge architectures.Distributed architecture can leverage self-organizing, self-healing IP / MPLS backhaul
Equivalent to core IP/MPLS (e.g. with MPLS VPN)Reduction in SP managed objects (e.g. EVC crossconnects, pseudowire tunnels)
Ethernet UNI
Ethernet UNI
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
Aggregation Node
BNGPPP, IP, MPLS MPLSMPLS / IP
DSL, Ethernet
Access Node
BNG
Distribution Node
Business E-LINE
Business E-LAN
EoMPLS PWEoMPLS Pseudowire VPLS
H-VPLS MPLS NNI
MPLS NNI
Port, 1:1 VLAN
Port, 1:1 VLAN
Port, 1:1 VLAN
Port, 1:1 VLAN
N:1, 1:1 VLAN modelsEoMPLS Pseudowire
N:1 VLAN modelIP/MPLS w. Multicast
EoMPLS PW
IP/MPLS NNI
Ethernet UNI
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 32BRKAGG-200114557_04_2008_c1
Operational Aspects—Provisioning
Single-edge architectures allow provisioning of all subscribers and services on a single system
e.g. facilitates QoS provisioning across services for the same subscriber using hierarchical schedulers
Multi-edge architecture leads to distributed provisioning for services destined to the same subscriber
Requires intelligent protocols for proper QoS management (e.g. ANCP)
Generation of significant amount of state information
Distributed architecture requires no per L2 service-instance provisioning/assurance in the aggregation network
Relies on diffserv mechanisms of IP/MPLS aggregation
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
17
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 33BRKAGG-200114557_04_2008_c1
Operational Aspects—Troubleshooting
Centralized architectures rely on transport tunneling mechanisms in the aggregation network
VLANs, PBT, Pseudowires, T-MPLS
Adds complexity for trouble-shooting the aggregation network
Single-edge architecture facilitates provisioning & trouble-shooting on a single system
Economies of integration
Multi-edge architectures can be trouble-shooted by service
Clustered or distributed architectures benefit from smaller number of subscribers and thus pinpointing of failures
MPLS/IP
MPLS/IP
Backhaul TunnelProvisioning & Maintenance
Subscriber Provisioning & Maintenance
Distributed Subscriber Provisioning & Maintenance
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 34BRKAGG-200114557_04_2008_c1
Service Availability
Distributed and clustered architectures typically employ smaller systems
Smaller fault-domains impact fewer subscribersLess risk of losing subscribers
Higher overall service availability
In-box redundancy can be used to ensure that certain failures are transparent to subscriber sessions
E.g. redundant routing / forwarding engines supported by Broadband high-availability features
Dual-homing ofDistributed edge nodes comparable to dual-homing of aggregation switches
Subscribers to distributed integrated edge systems (shorter loop lengths)
Centralized Single-Edge
Aggregation MPLS/IP/Ethernet
Failure Radius
Core
Distributed Single-EdgeFailure Radius
Core
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
18
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 35BRKAGG-200114557_04_2008_c1
Agg.
Agg.
Agg.
Traffic Patterns Affecting the Architectural Choice
Backhaul & Client/Server trafficTransits both BRAS and core
E.g.: HSI traffic, VoD traffic, Tunneled traffic
Multicast trafficSourced in the core and replicated at the BRAS
E.g.: broadcast TV
Traffic local to a BRASP2P traffic between users terminated on the same BRAS
E.g.: voice bearer traffic, P2P traffic;
Also applies to locally generated / sourced trafficIP / MPLS
CoreAgg.
IP / MPLS Core
IP / MPLS Core
IP / MPLS Core
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 36BRKAGG-200114557_04_2008_c1
Traffic Patterns—Architectural Considerations
High-bandwidth multimedia traffic is a standard service offering and must thus be considered by all architecturesBackhaul & Client-Server traffic is invariant to the different architectures
Policy enforcement close to subscriber may save backhaul bandwidth
Multicast traffic is efficient if replication happens close to the subscriber Saves bandwidth in the aggregation networkFavors multi-edge or distributed architectures
Traffic local to a BRAS can be handled more efficiently by distributed architecture
Optimized Routing for peer-to-peer routingLocal Video CachingService Interconnection to PSTN?Important for mobile traffic patterns!?BRAS IP Address allocation already supports this
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclusteredMulti-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
19
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 37BRKAGG-200114557_04_2008_c1
P2P Traffic
P2P applications (e.g. Skype, BitTorrent, Gnutella) have been main contributors to bandwidth growth in past years
Need to differentiate between P2P Downloads and P2P live streaming
P2P changes communication patternsPotential to keep more traffic localTraffic downloaded from closest users
But: so far, little empirical evidence how much traffic remains geographically local IP addresses carry no geographical significance -> different administrative domains
Source: http://www.cs.ucr.edu/~marios/Papers/UCR-CS-2007-05001.pdf
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 38BRKAGG-200114557_04_2008_c1
P2P Traffic—Impact of Video P2P Streaming
P2P overlays now considered for live video streaming (Coolstreaming, PPLive)
Flash crowd streamsChinese spring festival with up to 225K concurrent users @ 300 Kbps
Algorithm similar to BitTorrentStreaming server acts as source root Joining peer receives candidate list of peers who are able to stream (e.g. 50 peers)Joining peer then selects subset based on RTT (e.g. 5 peers) and receives buffer maps with streaming segmentsUpdated membership information continuously exchanged between peers to communicate state changes.Requested streaming segments received in both push & pull mode into receiving application buffer
Differentiation between IPTV and Internet TV using over-the-top distribution
IPTV: SP video streaming over closed IP networks
Source: HeavyReading, “Internet TV, Over-the-Top Video, & the Future of IPTV Services”, Vol. 5, No. 10, June 2007
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
20
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 39BRKAGG-200114557_04_2008_c1
Service Flexibility
Increasing requirement for value added servicesVoIP and Video services motivate SBCsApplication-aware services motivate DPI technologies, e.g. Most P2P traffic can no longer be identified at layer 4Security services gaining popularity
Single-edge architectures have more flexibility for quad-play servicesPay-as-you grow: incremental service roll-outIntegrated services could be realized either with service-blades or built-in
Distributed architecture more conducive for wholesaleFacilitates local wholesale modelL3VPN-based business or wholesale servicesPseudowire L2VPN services for business or wholesaleStill there are shared segments (QoS) in getting to the customer
DistributedCentralizedUnclustered Single-
EdgeClustered Multi-EdgeUnclustered Multi-EdgeClustered Single-EdgeUnclustered
Single-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 40BRKAGG-200114557_04_2008_c1
Service Flexibility: Security
Per-user firewalls and encryption increasingly demandedSignificant CPU requirements
Offers centrally managed security for broadband subscribers
Distributed architecture more conducive to integrated security servicesDropping packets close to subscriber saves backhaul
Localization of security attackes
faster mitigation leads to higher service availability
L2TP Internet
ASR 1000 LNS + IOS FW
LAC
ATM
IOS Firewall policies are downloaded from RADIUS and applied per subscriber on virtual access interfaces
RADIUS Syslog
DSLAM
PPPoXPPPoX
DSLRouter
DSLModem and PPPoEClient
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
21
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 41BRKAGG-200114557_04_2008_c1
Service Flexibility: Session Border Controller
Session Border Controllers (SBC) are critical to enable rich media video telecommunications across networks with simultaneous support for voice/video/data
SBC enables direct IP to IP Interconnect between multiple Administrative Domains for Session-Based Services:
Protocol Translation
Network Hiding / Security
Call Admission Control
Quality of Service (QoS)
Billing
TCL for customized applications
Toolkit of functions
Signaling Border Element (SBE)
H.323 SIP HA
AAA CDR
Policy
VPN Control
Session Control Interface
Data Border Element (DBE)
NAPT QoS HA
RTP Policy
SBC Architecture
Based on H.248
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 42BRKAGG-200114557_04_2008_c1
Service Flexibility: Deep Packet Inspection
Flexible Packet MatchingStateless packet matchingXML-based traffic description (protocol header description files)Can match on protocol stack, bit pattern, header fields
Network Based Application Recognition (NBAR)Identifies over 90 applications and protocols TCP and UDP port numbersStatically assignedDynamically assigned during connection establishmentNon-TCP and non-UDP IP protocolsData packet inspection for matching values
Distributed architectures allow more scalability
ToS SourceIP Addr
DestIP Addr
SrcPort
Sub-Port/Deep InspectionDstPort
Protocol
TCP/UDP Packet Data AreaIP Packet
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
22
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 43BRKAGG-200114557_04_2008_c1
Architectural Comparison Summary
Scalability – System Resources
?CapExScalability – Bandwith per SubscriberScalability – Policy Control & Enforcement
Scalability – TransportOperational – ProvisioningOperational – TroubleshootingService AvailabilityTraffic PatternService Flexibility
DistributedCentralizedUnclusteredSingle-Edge
Clustered Multi-Edge
UnclusteredMulti-Edge
Clustered Single-Edge
UnclusteredSingle-Edge
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 44BRKAGG-200114557_04_2008_c1
Sample NGN Broadband Architectures
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
23
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 45BRKAGG-200114557_04_2008_c1
Case Study 1: Distributed Unclustered Single-Edge
CPE
CoreAccess Edge(~5K)
PON
Agg.(~50K)
Core NetworkMPLS /IPIntegrated
Edge
10GEAccess Switch
CPE
SBC
MGW
POTSVV
VoIP Operators
LNS
ISP & Content
Providers
RACSApplications
B’cast TV
Video Conf
VoIP/SIP
VOD
…
H.248
Gq’
Service OfferingsVoice & Video Telephony (SBC, v6/v4)
IPTV VoD (SBC, HDTV, v6)Internet Access (BB, LAC, PPPoE, v4)
IPTV B’cast TV (Multicast, SDTV/HDTV, v6)
AAA/AAA/DHCPDHCP
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 46BRKAGG-200114557_04_2008_c1
CPEE-DSLAM
PE-AGG / UPE
SL
SL
Class A
Class C
Class B
• Treated as any other “trunk” network:
Could use perclass PQ+CBQ, oroverprovision
• Upstream anddownstream per ISP aggregate per class
- police
• No QOS required
BRAS/NPE Hierarchical QOS
SVLAN
SVLAN
• SVLAN shaping with sum of shaped rates allowed to exceed interface rate
• Configured by CLI
• Subscriber line level shaping• Sum of shaped rates can exceed SVLAN rate• Priority propagation for voip and video traffic• Configurable share of remaining bandwidth • Configurable overhead accounting• May be configured via CLI or using dynamically using RADIUS
Operational—Provisioning: 3-Layer Hierarchical QoS Scheduling
ASR 1000: available10000: available7600: available7200: available
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
24
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 47BRKAGG-200114557_04_2008_c1
Service Availability:Broadband High Availability
For PPPoX sessions terminated on the active route processor (RP):1. PPPoX session information is synchronized to standby RP 2. If active RP fails, PPP sessions become active on standby RP3. ATM virtual circuits and PPPoX session IP addresses maintained as they were before
on the primary RP
Works with NSF (OSPF, IS-IS, BGP)Supports In-Service Software Upgrades (ISSU)Up to 32,000 PPPoX sessions supported
ASR1000: 2H CY0810000: available7600: available
CPE
PPPoX
DSLAM
PPPoX
Cisco 10000ATM
RadiusServer
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 48BRKAGG-200114557_04_2008_c1
For L2TP sessions terminated on the active route processor (RP):1. L2TP control channel information is synchronized to standby RP (e.g. tunnel ID,
sessions IDs, data sequencing status etc) 2. If active RP fails, L2TP control channels become available on standby RP 3. PPPoX session carried in the L2TP tunnels and IP addresses maintained as they were
before on the primary RP
Works with NSF (OSPF, IS-IS, BGP)Supports In-Service Software Upgrades (ISSU)Up to 16,000 L2TP sessions supported
Service Availability:L2TP High-Availability
ASR1000: 2H CY0810000: End 2008
CPE
PPPoX
DSLAM
PPPoX
Cisco 10000ATM
L2TP
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
25
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 49BRKAGG-200114557_04_2008_c1
Case Study 2: Centralized Clustered Multi-Edge
Access Edge(~100)
DSL
L2 Aggregation(~600 | ~100)
GE BNG
Core
Core NetworkMPLS /IP
GE
GE
Applications
Video Conf
VoIP/SIP
VOD
…B’cast TV
B’cast TV
MSE
Residential
STB
Internet Voice
Business
Corporate
VoD / TV Business
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 50BRKAGG-200114557_04_2008_c1
Residential
STB
BRAS Cluster
Service Availability:BRAS Clustering with PADO-Delays
PPP Smart Server Selection allows user to configure specific PADO delay for a received PADI packet.
Can be configured per bba-group or based on circuit-id/remote-id
In case of an outage of a BRAS in the cluster, other BRAS stand ready to accept subscriber sessions
Detection of failure possible at both ends of PPPoE session because of missing keepalives
Subscriber sessions have to be re-established
Allows BRAS redundancy with predictable behavior
E-DSLAMEthernet
Aggregation
PADI1
PADI
PADO
PADIPADI
PADO
PADO
2PADO
3PADR
4PADS
PADR
PADS
Delay
PPPoE
ASR1000: 2H CY0810000: available
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
26
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 51BRKAGG-200114557_04_2008_c1
Application Provider
AAA
Access Provider
AAA
L2-EthernetAccessNetwork L3 Core
DHCP Server
1. User PC initiates a PPP session. ISG creates session and defaults service are installed.
2. ISG authenticates user and retrieves user profile.
3. ISG retrieves service profile for auto-logon service. A policy directive stipulates that further authentication is required.
4. ISG authenticates service using username & password retrieved from user profile.
5. ISG install new service and user has full access to service.
User PC
1
2
3 4
5
Service Availability:Intelligent Services Gateway (ISG)
ISG handles the key aspects of service control:
Subscriber identification
Service and policy determination
Session policy enforcement
Session life-cycle management
Accounting for access and service usage
Provides dynamic provisioning and activation of services
Open, standards-based interfaces
Support smooth transformation from PPP to IP
ASR1000: 2H CY0810000: available7600: available7200: available
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 52BRKAGG-200114557_04_2008_c1
Policy Control and Enforcement:ISG-SCE Common Control Bus
Service Control Engine (SCE) operates as delegate of the Intelligent Services Gateway (ISG) through a common control-bus:
ISG establishes subscriber-contexts on SCE and enforces policiesSCE provides ISG with application-layer accounting; ISG combines into master accounting records and communicates to OSS
BenefitsSingle northbound interface from ISG (BRAS)Single Unified subscriber databaseCAPEX/OPEX optimized deployment:
Only need to integrate with one platform (ISG)Reduced resource requirements on AAA/policy layer
Increased Scale and Reliability
SCE
SCE Mngmt
ISG
AAA
ISG SCE
AAA
Policy & Auth
Accounting
Policy & Auth
AccountingControl Bus
TODAY:ISG and SCE deployed independently
ISG and SCE integrated
ASR1000: 2H CY0810000: available7600: available
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
27
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 53BRKAGG-200114557_04_2008_c1
Policy Control and Enforcement:Dynamic Policies
Dynamic service policies: QoS Policy Maps constructed by ISG with RADIUS-based parameter inputs
RADIUS communicates parameter values using Cisco 250/252 VSA
Hierarchical ISG service policy must exist for the ISG subscriber session
Acts as default policy map in case no RADIUS parameterizations are received for a session
Dynamic policies always take precedence over the default policies
Dynamic RADIUS operations:Adding and removing classes
Adding and removing actions: shape, police, priority, bandwidth, and set coscommands
Modifying the average rate for the above actions
Activating and deactivating child policy maps
10000: End 2008
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 54BRKAGG-200114557_04_2008_c1
Policy Control and Enforcement:Dynamic Policies—Example
First-sign-of-life Example: CoA Example:policy-map Policer
class policer-tc
accounting aaa list AAA_List
police input 8000 10000 12000
police output 8000 10000 12000
The ISG receives the following parameterized ISG policing VSA in a CoAmessage:
252 binary 0b suffix “policer(acct_mlist=AAA_List,cirin=9000,cbrin=11000,ebrin=13000, cirout=9000, cbrout=11000, ebrout=13000”
The ISG copies the original Policer policy and processes the VSA to create the following parameterized transient policy named Policer1:
policy-map Policer1
class policer-tc
accounting aaa list AAA_List
police input 9000 11000 13000
police output 9000 11000 13000
CPE DSLAM ISG RADIUS
1 Session start (FSOL)
2Install default
policies
3 Access Request
4Retrieve
Parameters
5Access Accept
6Install dynamic
policies
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
28
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 55BRKAGG-200114557_04_2008_c1
Case Study 3: Centralized Clustered Multi-Edge
CoreAggregationAccess Edge
Dist-node
BRAS
SR/PE
DPI
Core NetworkMPLS /IPAggregation Network
MPLS/IP
Dist-node
Identity Address Mgmt
Portal Subscriber Database
Monitoring Policy Definition
Billing
Policy Control Plane (per subscriber)
Cable
PON
DSL
ETTX
Residential
Residential
STB
Business
Corporate
Content Farm
VOD TV SIP
STB
Content Farm
VOD TV SIP
☺Mobile
Cable
MSPP
L2 P-to-P (local or xconnect)L2 MP local bridgingL2 MP VPLSL3 routed
UntaggedSingle taggedDouble tagged802.1q802.1adetc
Aggr-Node
7600 with ES-20 Line Cards
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 56BRKAGG-200114557_04_2008_c1
Flexible VLAN
TagMatching
Flexible VLAN
TagMatching
H-QoSPer VLANH-QoS
Per VLAN
L3L3
EoMPLSEoMPLS
VPLSVPLS
Local connect (P2P)Local connect (P2P)
Local Bridging (MP)Local Bridging (MP)
SecuritySecurityFlexible
VLANTag
Rewrite
Flexible VLANTag
Rewrite
Service Instance (Ethernet Flow Point)
EVC
Ethernet Virtual Connection (EVC) Overview
One service instance (EFP) can match one or multiple or range of VLANs at a time
One service instance (EFP) can match one or multiple or range of VLANs at a time
Flexible L2/L3 service mapping, one or groups of EFPs can map to same EVC
Flexible L2/L3 service mapping, one or groups of EFPs can map to same EVC
Per service featuresPer service features
• VLAN local port significance• Two VLAN tag aware• Flexible VLAN tag matching (combination of up to two tag)
• VLAN local port significance• Two VLAN tag aware• Flexible VLAN tag matching (combination of up to two tag)
Flexible VLAN tag manipulation, pop/push/translateFlexible VLAN tag manipulation,
pop/push/translate
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
29
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 57BRKAGG-200114557_04_2008_c1
Summary
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 58BRKAGG-200114557_04_2008_c1
Summary
Multimedia Services challenge existing broadband aggregation architecturesBroadband architectures can be distinguished along different dimensions
Geographical distribution (centralized vs. distributed)Single-edge vs. multi-edge policy enforcementClustered vs. unclustered
Centralized multi-edge broadband aggregation architecture can be evolved to facilitate the introduction of multimedia servicesClustering or multi-edge approaches improve overall service availability
Failures affect a smaller number of subscribers
Distributed single-edge services architecture provides required flexibility for quad-play multimedia services
Combines scalability with operational advantages
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
30
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 59BRKAGG-200114557_04_2008_c1
Q and A
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 60BRKAGG-200114557_04_2008_c1
Recommended ReadingK. Reddy, “Building MPLS-Based Broadband Access VPNs”, Cisco Press, Nov. 2004, ISBN-13: 978-1-58705-136-4.
R. Wood, “Next-generation Network Services”, Cisco Press, Nov. 2005, ISBN-13: 978-1-58705-159-3.
K. Lee, F. Lim, B. Ong, “Building Resilient IP Networks”, Cisco Press, Dec. 2005, ISBN-13: 978-1-58705-215-6
T. Szigeti, C. Hattingh, “End-to-End QoS Network Design: Quality of Service in LANs, WANs, and VPNs:, Cisco Press, Nov. 2004, ISBN-13: 978-1-58705-176-0
B. J. Carroll, “Cisco Access Control Security: AAA Administration Services”, Cisco Press, May 2004, ISBN-13: 978-1-58705-124-1.
I. Pepelnjak, J. Guichard, J. Apcar, “MPLS and VPN Architectures, Volume II”, Cisco Press, Jun. 2006, ISBN-13: 978-1-58705-112-8.
I. Pepelnjak, J. Guichard, “MPLS and VPN Architectures”, Cisco Press, Oct. 2000, ISBN-13: 978-1-58705-002-2.
Available Onsite at the Cisco Company Store
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
31
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 61BRKAGG-200114557_04_2008_c1
References
Other Interesting CiscoLive Networkers 2008 SessionsBRKAGG-2000: Implementation and utilization of Layer 2 VPN Technologies
BRKOPT-2302: Policy Control Architectures for Next Generation Networks: Standards and Reality
TECAGG-2003 Layer 2 Virtual Private Networks – Converged IP/MPLS Network
BRKNMS-2051 Optimizing a Service Provider Infrastructure for IPTV Services
BRKOPT-2111 Carrier Ethernet Aggregation Networks for Business and Residential Services
BRKVVT-2101 IPTV Service Architecture Design and Deployment
HeavyReading, “IP Video and the New Broadband Edge”, Vol. 3, No. 20, Dec. 2005.
HeavyReading, “Internet TV, Over-the-Top Video, & the Future of IPTV Services”, Vol. 5, No. 10, June 2007.
M. Iliofotou, P. Pappu et al., “Network Traffic Analysis using Traffic DispersonGraphs (TDGs): Techniques and Hardware Implementation”, available from http://www.cs.ucr.edu/~marios/Papers/UCR-CS-2007-05001.pdf
Ellacoya Networks, “Ellacoya Data Shows Web Traffic Overtakes Peer-to-Peer (P2P) as Largest Percentage of Bandwidth on the Network “, http://www.ellacoya.com/news/pdf/2007/NXTcommEllacoyaMediaAlert.pdf
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 62BRKAGG-200114557_04_2008_c1
Complete Your Online Session Evaluation
Give us your feedback and you could win fabulous prizes. Winners announced daily.
Receive 20 Passport points for each session evaluation you complete.
Complete your session evaluation online now (open a browser through our wireless network to access our portal) or visit one of the Internet stations throughout the Convention Center.
Don’t forget to activate your Cisco Live virtual account for access to all session material on-demand and return for our live virtual event in October 2008.
Go to the Collaboration Zone in World of Solutions or visit www.cisco-live.com.
© 2006, Cisco Systems, Inc. All rights reserved.Presentation_ID.scr
32
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 63BRKAGG-200114557_04_2008_c1
© 2008 Cisco Systems, Inc. All rights reserved. Cisco Public 64BRKAGG-200114557_04_2008_c1
Backup
top related