SPARC: use-cases and results Requirements and Controller Architecture
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Transcript of SPARC: use-cases and results Requirements and Controller Architecture
SPARC: use-cases and results Requirements and Controller Architecture
Wolfgang John
November 23th 2012
Split Architecture for Carrier-Grade Networks.
EU FP7 Project Start date: July 2010; End date: November 2012 (1 week ago …) 6 Partners:
ER Kista ER Budapest=
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Mission: Applying Software Defined Networking (SDN) to operator networks Results
23 publications, presentations and demos (GENI engineering conference, World Telecommunication Congress, Globecom, etc.)
Standardization impact in ONF and IRTF
Key Project Deliverables D2.2: Use cases, requirements, techno-economic study (CAPEX and OPEX), business
environment D3.3: Main technical document, study of architecture and required extensions D4.2: Documentation of specific OpenFlow extensions D4.3: Technical documentation of implementation and prototyping activities D5.2: Results of validation and performance evaluation Movie: Summarizing the most important demo’s
(Soon) all to find on: http://www.fp7-sparc.eu
Split Architecture for Carrier-Grade Networks.
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SPARC.Project Team.
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LSR
Optical transportOptical transport
BRAS
Backbone
LERAGS2
GPON OLT
AGS1
Outdoor DSLAM
DSLAM
Business
Business
RGW
Switch / Router
Data Centre
Other Service Platforms (mobile,
business, IPTV, VoIP, ...)
Access/Aggregation
AAAAuto-
configuration Network
Management Service
Management
OAM subsystem
Use Case Areas.Focus on Access/Aggregation.
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The vision of SPARC is to define, implement & evaluate a scalable carrier class Split Architecture.
Seven objectives of SPARC, with the three main objectives highlighted: Definition of typical use cases for Split Architecture (D2.2) Analysis and description of business potential (D2.2)
Definition of Split Architecture blueprint (D3.3) Extension of the OpenFlow protocol (D3.3 and D4.2) Development of SPARC prototype (D4.3)
Validation of SPARC prototype (D5.2) Exploitation of results (papers, demos, presentations, videos)
SPARC.Main Objectives.
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What is carrier-grade? Scalability
Support large-scale deployments for carrier-grade networks. E.g. a controller shall be able to control forwarding devices that could count in the order of hundreds.
Availability and Reliability The availability of networking services shall be equivalent to that of traditional
technologies. Network and service management
The ability to monitor, diagnose and centrally manage the network Quality of Service
Allowing the assurance of SLAs using QoS guarantees for service attributes (e.g. rate, loss, delay) and service isolation
Support for legacy technology allowing deployment of new services in parallel to existing legacy protocol stacks
SPARC Objectives.Carrier-grade.
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SPARC Requirements and Study Topics.Overview.
Requirements (study topics) from WP2
WP3: Problem and Solution Description
WP4: OF Extensions WP4: Prototype Integration /Implementation
WP5: Validation / Performance Evaluation
Controller Architecture Yes Yes Yes Yes
Network Management Yes No No No
Service Creation Yes Yes Yes Yes
Virtualization & Isolation Yes Yes Yes Yes
OAM Yes Yes Yes Yes
Openness & Extensibility Yes Yes Yes Yes
Control Channel Bootstrapping & Topology Discovery
Yes N/A Yes Yes
Network Resiliency Yes N/A Yes Yes
Energy-Efficient Networking Yes Yes No No
Quality of Service Yes No No No
Multilayer Aspects Yes No No No
Scalability Yes (numerical validation)
N/A N/A Yes
1
2
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control
data
control
data
control
data
(I) today’s network design
control
data
app app app
data data
OpenFlow
(II) generic OpenFlow architecture proposed initially by Stanford
SDNcontrol
softwarenetwork services
OpenFlow
data data data
(III) SDN specified by the ONF
business applications
Intro to SplitArchitecture.Evolution of SDN.
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• OpenFlow-based SDN model, defined by the ONF
Intro to SplitArchitecture.Software-Defined Networking.
data data data
SDNcontrol
softwarenetwork services
business applications
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• OpenFlow-based SDN model, including a network hypervisor– Virtualization and abstraction layer– Position of hypervisor (below or above NOS) debatable
Intro to SplitArchitecture. Software-Defined Networking.
data data data
SDNcontrol
softwarenetwork services
business applications
control program
data data data
hypervisor
network operating system
business applications
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• SPARC SplitArchitecture– Again a split between data and control plane– Forwarding and processing in data plane considered separately
Intro to SplitArchitecture.The SplitArchitecture concept.
control program
data data data
hypervisor
network operating system
business applications
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• SPARC SplitArchitecture– Again a split between data and control plane– Forwarding and processing in data plane considered separately
Intro to SplitArchitecture.The SplitArchitecture concept.
OpenFlow
hierarchical controllerconcept
forwarding forwarding forwarding
processing processing processing
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• SPARC SplitArchitecture– Initial considerations on the role of network management
Intro to SplitArchitecture. The SplitArchitecture concept.
network management
system
OpenFlow
hierarchical controllerconcept
forwarding forwarding forwarding
processing processing processing
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• SPARC SplitArchitecture– Recursively stacked control planes– Abstracted network view ot higher planes via OpenFlow Interface
Intro to SplitArchitecture. The SplitArchitecture concept.
OpenFlow
OpenFlow
hier. control plane n+1
hier. control plane n
hier. control plane n-1
app
app
app
OpenFlow
hierarchical controllerconcept
filtered,abstract network
view
forwarding forwarding forwarding
processing processing processing
network management
system
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Intro to SplitArchitecture. The SplitArchitecture concept.
network management
system
OpenFlow
OpenFlow
hier. control plane n+1
hier. control plane n
hier. control plane n-1
app
app
app
OpenFlow
hierarchical controllerconcept
filtered,abstract network
view
forwarding forwarding forwarding
processing processing processing
• SPARC SplitArchitecture– Recursively stacked control planes– Abstracted network view ot higher planes via OpenFlow Interface
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• Goals for a carrier-grade control layer:– Increase flexibility
• Adapt control architecture to use-cases and business models• Distribute the control layer to adapt to network capabilities• Allowing both cross-layering and strict layering of control logic
– Increase scalability• Operator networks are complex
-> divide and conquer the problem space– Allow smooth migration
• Supporting control protocol operations with legacy domains
Hierarchical controller.Design goals.
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CPCP CPCP CPCP
DPDP DPDP DPDP
CP peers talk OSPF, IS-IS, STP, etc.
FWD engine (DP) and control logic (CP) sit jointly on a single network element
Hierarchical controller.
• Current situation: monolithic network elements
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DPDP DPDP DPDP
CPCP CPCP CPCP
OpenFlow
But still the old situation the CP peers control a single network element and use the old protocol for sharing state as before (OSPF, IS-IS, LDP, STP, …)
Hierarchical controller.Splitting Ccontrol and forwarding.
• Step 1 of SDN: Splitting control from data plane
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• Step 2 of SDN: Centralize control plane
Hierarchical controller.Centralizing control.
Benefit: no complex protocols for sharing state among CP peers required any more.
Centralized control logicCentralized control logic
DPDP DPDP DPDP
OpenFlow
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Centralized control logicCentralized control logic
DPDP DPDP DPDP
Domain acts like a backplane within the emulated data path element.
OpenFlow
Mgmt API
• SPARC Idea #1: Exposing services via OpenFlow again!
Hierarchical controller.OpenFlow as northbound interface.
OpenFlow
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Flowspace MgmtFlowspace Mgmt
Hierarchical controller.Flow space registration.
Centralized control logicCentralized control logic
DPDP DPDP DPDP
Higher layer controllers subscribe to parts of the flowspace (i.e. slices)Replace the pub/sub interface (as in NOX) with flowspace reservation
OpenFlow
Mgmt API
OpenFlowOpenFlow
OpenFlow
• SPARC Idea #2: Integrate FlowVisor functionality into controller
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Requires OpenFlow protocol extensions for management of:* Flowspaces: allow plane (n) to register a slice of the flowspace on (n-1)* Transport endpoints: allow plane (n) to control (CRUD) logical ports on (n-1)
• Result: Hierarchical structuring of control planes!
Hierarchical controller.Stacked control planes.
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IPIP
ETHETH ETHETH
04/22/23
PHYPHY PHYPHY
SMTPSMTP
IPv4IPv4 IPv6IPv6
ETHETH ETHETH
PHYPHY PHYPHY
An IP router use case: build an IPv4/IPv6 router
An SMTP router use case: build a Mail Transport Agent (MTA)
DPDP
SMTPSMTP
ETHETH
IPv4IPv4
OpenFlow
PHY-CTLPHY-CTL
ETH-CTLETH-CTL
APP-CTL APP-CTL
IP-CTLIP-CTL
=
• IP-CTL emulates a single IP layer• ETH-CTL emulates Ethernet host stacks• PHY-CTL is a data path element
The northbound interface is OPENFLOW!
Hierarchical controller.Example: protocol stack.
• Example: Modular layering of a controller
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• SPARC SplitArchitecture– Initial considerations on the role of network management
Considerations on network management. The SplitArchitecture concept.
network management
system
OpenFlow
OpenFlow
hier. control plane n+1
hier. control plane n
hier. control plane n-1
app
app
app
OpenFlow
hierarchical controllerconcept
filtered,abstract network
view
forwarding forwarding forwarding
processing processing processing
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Considerations on network management.Control vs. management.
• Boundary between management and control is blurred– Management functions are important in SplitArchitecture
Today’sNetwork
Management
SplitArch/SDN
Functionality(Increased control granularity)
Automation(Program driven, automatic adjustment
of the network)
Speed(Beyond human time-scale)
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• Which NM functions to embed in a controller?– Q1: Already an essential part of SplitArchitecture/SDN control?
If not,– Q2: Facilitates timely and automated configuration and flow steering?
If so,– Q3: Possible with open and standardized extensions to the OF / OF-
Config protocols? (no bloating with vendor or device specific models)• Apply this question to NM function according the TMN/FCAPS
definitions of network management
Considerations on network management.Assessment of functions.
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NM function FCAPS Groups Q1 included? Q2 timely?
Q3 open interfaces?
Proposed CP integration
Element management functions:Firmware management config no no no noDevice monitoring (temp., etc) performance no no no noDevice monitoring: Power consumption performance no yes¹ OF-mon yes¹Control network bootstrapping config no no no noResource and capability discovery config yes no OF, OF-config yesLogical swtich instatiation config yes no OF-config yesControl channel (addresses and credentials) config / security yes no OF-config yesFault detection (equipment) fault no no no noAlarm management configuration no yes OF-config yesLogging of alarms fault, accounting no no no noLogging of statistical data performance, accounting no no no noResource usage (cpu, buffer, queue-length) performance no yes² OF-mon yes²Network management functions:Topology discovery (creation of network view) config yes yes OF yesPath computation & setup config yes yes OF yesFlow table management config yes yes OF yesTunnel management config yes yes OF-config yesTraffic engineering (creation of QoS paths) config yes yes OF yesFault detection (link level) fault yes³ yes OF-mon yesLink performance monitoring performance no yes OF-mon yesNetwork performance optimization performance no yes OF, OF-config yesResiliency measures performance/config yes yes OF, OF-config yesService management functions:Accounting accounting no no no noUser management and AAA accounting / security no no no noService definition and administration config no no no noService OAM configuration config no yes OF-config yes*QoS management (service delay, loss) performance no yes OF-mon yes*SLA management accounting no no no no
¹ for energy-aware networking (see section 5.7)² for logical switches sharing switch resources (see section 5.2.4)³ implemented in SPARC as BFD (see section 5.3.3)* assuming service controller functionality in the CP, as in SPARC D4.3
Considerations on network management.SPARC assessment example.
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Control and management architecture.Summary.
• Result: A recursive and modular control plane architecturecontrol plane A control plane B
e.g. optical devices
network management
system
OpenFlow
hierarchical controllerconcept
forwarding forwarding forwarding
processing processing processing
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SPARC: use-cases and results SPARC prototype implementations
Wolfgang John
November 23th 2012
Seamless MPLSaka carrier grade packet transport
• Seamless MPLS “…architecture which can be used to extend MPLS networks to integrate
access and aggregation networks into a single MPLS domain…” draft-leymann-mpls-seamless-mpls-03
Forklifting access/aggregation to MPLS may be too expensive apply SDN principles for Seamless MPLS
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Central element
IP/MPLS coreAggregationIP EdgeAccess GW
Service
SwitchSwitch
Switch
CPCP
CP
OpenFlow
IPMPLS IP
MPLS
IPMPLS
OSPF, LDP,RSVP-TE, BGP …
CP
CPCP
CP
SPARC Controller
Pro
toco
lP
roxy
CP
APP (CP) APP (CP)
Seamless MPLS implementation.Basic concept.
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1. Topology discovery of MPLS aggregation & core2. Management of MPLS LSPs in aggregation3. Signal end-to-end MPLS LSPs 4. Provision MPLS transport services (e.g. Pseudowire)
Video
WEBClient
MPLSCP
MPLSCP
MPLSCP
OFSwitch
OFSwitch
OFSwitch
OFSwitch
OFEdge
OFEdge
IP/MPLS coreOPENFLOW MPLS Aggregation
NNIOSPF, LDP
OFSwitch
CoreMPLS
CoreMPLS
CoreMPLS
ServicesClients
Client
SPARC Controller
NOX Kernel
OpenFlow MPLS CTRL
Pro
toco
l Pro
xy
OS
PF
LDP
End-to-end MPLS CTRL
Discovery
Seamless MPLS implementation.Essential Functionalities.
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IP/MPLS coreOPENFLOW MPLS Aggregation ServicesClients
MPLSCP
MPLSCP
CoreMPLS
CoreMPLS
CoreMPLS
MPLSCP
OFSwitch
OFSwitch
OFSwitch
OFSwitch
OFAccess
OFAccess
OFSwitch
Video
WEB
Client
Client
NOX Kernel
DiscoveryDiscovery
Pro
tocol P
roxy
Pro
tocol P
roxy
OS
PF
OS
PF
Combine OpenFlow and legacy topology discovery information
Seamless MPLS implementation.1. Topology disovery of MPLS aggegation & core.
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IP/MPLS coreOPENFLOW MPLS Aggregation ServicesClients
MPLSCP
MPLSCP
CoreMPLS
CoreMPLS
CoreMPLS
MPLSCP
OFSwitch
OFSwitch
OFSwitch
OFSwitch
OFAccess
OFAccess
OFSwitch
Video
WEB
Client
Client
SPARC Controller
NOX Kernel
OpenFlow MPLS CTRLOpenFlow MPLS CTRLDiscovery
• Installs PtP, MPtP and PtMP tunnels
• Reconfigures them upon topology changes
Seamless MPLS implementation.2. Management of MPLS LSPs in aggregation.
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IP/MPLS coreOPENFLOW MPLS Aggregation ServicesClients
MPLSCP
MPLSCP
CoreMPLS
CoreMPLS
CoreMPLS
MPLSCP
OFSwitch
OFSwitch
OFSwitch
OFSwitch
OFAccess
OFAccess
OFSwitch
Video
WEB
Client
Client
• Topology synchronization with OSPF
• Spans end-to-end MPLS with LDP• Nests them in MPtP tunnels in
aggregationSPARC Controller
NOX Kernel
OpenFlow MPLS CTRL
Pro
tocol P
roxy
Pro
tocol P
roxy
OS
PF
OS
PF
LD
PLD
P
End-to-end MPLS CTRLEnd-to-end MPLS CTRL
Discovery
MPLS Tunnel MPLS Tunnel
Seamless MPLS implementation.3. Signaling end-to-end MPLS LSPs.
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Split-BRAS
• Split-BRAS BRAS is complex and expensive integrated node since it must handle all
subscriber traffic, hence it must cope with continuously increasing capacity need, this means increasing cost
Traditional way of deploying BRAS will not scale apply SDN principles to distribute BRAS functionality
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RAWBRAS
AN
AGS 1
AGS 2
BRAS RADIUS
Client(RGW)
PPPoE tunnel
AN
AGS 1
AGS 2
RADIUS
Client(RGW)
PPPoE tunnel
Control session
AN
AGS 1
AGS 2
Client(RGW) PPPoE tunnel
IP Edge
RADIUS
Control session
Aggregationspecific tunnel
Common residential model today with PPPoE
Split Control and raw forwarding
Roll raw BRAS towardAccess Node
RAWBRAS
Split BRAS.Basic concept.
Control session
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Applying a recursive
control plane
data path element
control plane A control plane B
L2 fwd engine (disabled)
EoPhy
L3 fwd engine
IPoEPPP & PPPoE
EoPhy
Split BRAS.Architecture Blueprint.
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Central element
IP/MPLS coreAggregationIP EdgeAccess GW
SPARC Controller
Split BRAS.Concept.
RAWBRAS
Relay PPP Request
Ethernet IP/MPLS
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Central element
IP/MPLS coreAggregationIP EdgeAccess GW
SPARC Controller
Split BRAS.Flexible placement.
RAWBRAS
SwitchSwitch
Switch
PPPoE (over PWE)
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Central element
IP/MPLS coreAggregationIP EdgeAccess GW
SPARC Controller
Split BRAS.Increased scalability.
SwitchSwitch
Switch
PPPoE (over PWE)RAWBRAS
RAWBRAS
IP/MPLS
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Summary of SPARC OpenFlow Protocol Extensions implemented.
• MPLS– Parsing MPLS headers– Basic MPLS actions: push/pop header, change TTL, …
• PPP & PPPoE– Terminate PPP & PPPoE tunnels
• Connectivity Check– Pro-active monitoring of contuity with probe packets of MPLS-TP BFD format– Used for monitoring adjacency and flow pairs (bidirectional path)
• OAM & Protection Notification– About state changes of monitoring entities– About protection events
• Pseudo Wire– Support for Ethernet Pseudo Wire over MPLS PSN– Not full implementation (i.e., no sequence numbers)
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