View
6
Download
0
Category
Preview:
Citation preview
SDN: A NEW PARADIGM Kireeti Kompella CTO, JDI
2 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
AGENDA
What is SDN? § Definition and goals of SDN § Analogy with Compute Virtualization § Orchestration for Agile Service Provisioning § Unified SDN
What parts of the network does SDN touch?
Conclusion
3 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
DEFINITION AND GOALS OF SDN
SDN has many definitions and many goals Separation of control
and data planes Interoperability, innovation,
higher feature velocity
OpenFlow-based data plane
Standardized, powerful
Increasing use of CPUs (Intel “x86” processors)
General purpose, cheap, ubiquitous
Next-gen provisioning: abstract service creation
Lower OpEx, faster service delivery
Separation of control and data planes
Programmability, more network control
4 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
SEPARATION OF CONTROL AND DATA PLANES CENTRALIZATION OF CONTROL PLANE à “NOS”
Data Plane
Control
Data Plane
Control
Data Plane
Control
…
Network Operating System
Network Application
Network Application
Network Application
Network State Transform via Network Apps
5 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
IS A ROUTER JUST CONTROL AND DATA PLANE?
Data Plane
Control
Data Plane
Control
Data Plane
Control
…
Mgmt Mgmt Mgmt
Academic view of a router
Actuality of a
router
Interoperable (more so than not)
Not standardized;
not at all interoperable!
This is where services live
This is also where agility
is needed
6 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
RESTORING AGILITY: SEPARATE MANAGEMENT FROM REST OF ROUTER
Data Plane
Control
Data Plane
Control
Data Plane
Control
…
Mgmt Mgmt Mgmt
Orchestration Layer
The goal: service agility via orchestration:
freedom from “physics”, process, bureaucracy
RESTful APIs APIs are for defining and
controlling the orchestration
7 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
ORCHESTRATION = AGILE SERVICE PROVISIONING
Just as in Compute Virtualization, so in networks: we need the ability to orchestrate and automate
§ In this case, service creation and management
This offers greater network control and speeds up service rollout § Dual effect of an increase in revenues and lower OpEx § It will also improve resource efficiency, leading to CapEx savings
But how is this different from current Network Management Systems, or OSSs?
8 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
DISCUSSION: WHY PROGRAMMABILITY?
Cool! New
control plane!
really?
9 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
ANALOGY: COMPUTE VIRTUALIZATION First came the technology (actually, quite long ago)
§ “Let’s emulate virtual CPUs on a physical CPU”
Then came orchestration and automation § Bring up manage, terminate, new VMs
Finally, came the realization § “I’m free from the constraints of physics!” § and the constraints of process, bureaucracy
Instead of a few months to deploy an application § agonize over how many servers are needed,
purchase, rack and power them, connect them up
… it can take a few hours, or even a few minutes § especially with the help of automation
10 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
PROGRAMMABILITY IS MOSTLY ABOUT AUTOMATION
Automation allows repetitive tasks to be done easily, quickly and in an error-free manner
Automation allows pre-programmed responses to events: § faults, congestion, bandwidth surges, bandwidth requests, …
Automation allows humans to offload what they don’t do well … § quick, accurate responses to anticipated events
… to get on with what humans do best: § defining new services, defining policies, monitoring for
unanticipated events and providing customized responses
This means that the language in which this automation is expressed needs to be suited for the purpose
11 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
DISCUSSION: WHY PROGRAMMABILITY?
Practical, efficient, gets the job done
practical, efficient, sexy-ish
12 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
SERVICE ABSTRACTION
Service definition is based on abstract information models § These are high-level: device and OS and version independent § They are standardized, but allow for provider-specific
enhancements § Service deployment is transformation of an abstract service
definition to device-specific data models
In this system, service deployment will be: § Fungible – I can use a given device for many services § Flexible – I can deploy a service at many devices (placement) § Fast – I can roll out a service quickly, redeploy quickly
§ Responsive – the service adapts dynamically to changes
Provisioning
Analytics and Automation
13 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
service reqts
High-level, declarative specification of service requirements
Parse specification Process analytics
Device 1
Device 6
Device 5
Device 4
Device 3
Device 2
Network Analytics
Service configuration
lives here
SDN AS A COMPILER SAY WHAT YOU WANT, NOT HOW TO DO IT
Configuration is sent to chosen device
Process &
compile
A DB
SDN system S
DB
14 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
UNIFIED SDN
SDN Transformation Engine
Service model 1
Service model 2
Service model 3
Device model 1
Device model 2
Device model 3
OSS/Orchestration
Device 1 Device 3 Device 4 Device n Device 2
Access Edge/NFV/DC Core/Inter-DC
Abstract
Device level
15 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
CUSTOMIZATION OF SERVICE MODELS AND DEVICE MODELS
Service Template
Standard model for some service
Customized service model for use case
Customized Service Model
Service Instance for
some customer
Customized Service Instance
Base device model
Standard device level model for
service
Vendor-customized device level model
Device instance
Device model for service instance
device model
Customized
aka programmability
16 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
SDN AS A COMPILER WITH PLUGINS TO HANDLE CUSTOMIZATIONS
Service Instance Template
Customized Service
Template
Device level
model
Device level
model
Customized Service Instance
Base Compiler
Plugin for specific
use case
Plugin for Device
Device
instance
Plugin for specific
resource optimization
Use case specific features
Device-specific feature
17 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
AGENDA
What is SDN?
What parts of the network does SDN touch? § Virtualized Data Centers § SDN for NFV § Core SDN § Access/Edge SDN
Conclusion
18 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
WHAT PARTS OF THE NETWORK DOES SDN TOUCH?
ACX4000/MX104
ACX4000/MX104
MX240/480
MX240/480
MX960
MX960
ACX1000
BUSINESS ACCESS
RESIDENTIAL ACCESS
ACX1000
ACX1000
MOBILE ACCESS
CONVERGED ACCESS/ HUB-SITE ROUTER
AGGREGATION ROUTER
CELL-SITE / CPE
EDGE ROUTER
CEN Access (CKT/ETH/MPLS)
CEN aggregation (MPLS)
CEN Core (MPLS)
MU
X/
DE
MU
X
amp amp amp amp
Core
amp amp amp amp
MU
X/
DE
MU
X
MU
X/
DE
MU
X M
UX
/D
EM
UX
SERVICE CENTER
To other metros
Virtualized DC
Access SDN Edge SDN
NFV
WAN SDN: Centralized and Multi-Layer Traffic Engineering
19 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
SDN FOR VIRTUALIZED DATA CENTRE
Service Nodes
Internet VPN DCI WAN
Gateway Router
JunosV Contrail
Orchestrator
Compute APIs Storage APIs Network APIs
Server
Virtual Machine vRouter
Physical Switches
vSRX, F5 …
Orchestration of Compute (Virtual Machines) in a
Virtualized DC is mature
One can, via the Contrail controller, define “Virtual
Networks” (VNs), inter-VN policies and service chains, as high-level data models
When a VM is placed on a server, the Network
Orchestrator calls into to Contrail to connect the VM to its VN, and has all the
policies it needs
20 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
NETWORK FUNCTION VIRTUALIZATION
SERVICE CENTER
NFV is the use of general purpose servers instead of specialized devices for network functions such as voice
gateways, video encoders, IMS, MME, firewalls, DPI, etc.
Virtualized Network Applications
KVM Hypervisor
Linux
Host/ Cluster Manager
Virtualized Network Applications
KVM Hypervisor
Linux
Host/ Cluster Manager
VMs VMs
21 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
NFV ORCHESTRATION
Orchestrator
Compute Models
Internet VPN DCI WAN
Gateway Router
Network Models
Abstract specification of services and service chain
Instantiate services
Create service chain
Servers
Specification of services includes details of instances and config; and details of the connecting service chain
22 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
SDN FOR THE EDGE
Process &
compile A DB
SDN system S
DB
Core Edge
CPE
Agg2
Service Instance1
Service Instance2
Service Instance3
Service instance database
Real-time telemetry
Access Network
Analytics database
Program devices
Service instances defined via service
data models
Self-Service Portal
The value of automation!
23 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
CORE (OR WAN) SDN: PATH OPTIMIZATION
SDN in the core of the network focuses on optimized multi-layer Traffic Engineering based on centralized path computation
There is a thoughtful separation of functions into those that are distributed and those that are centralized
The goal is to have a higher-level view of TE, and to make this TE serve the needs of services
24 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
CORE SDN: MULTI-LAYER PATH COMPUTATION & BANDWIDTH CALENDARING
POP POP POP
POP POP POP
POP POP
Note: only a small subset of the paths (2 paths) are shown. Backup Primary
Control Node
Management Node
Abstract, network-wide
LSP reqts
Centralized Path Computation
Distributed topology discovery
Distributed signaling
PCEP
BGP-TE
Different application, different domain, but same SDN paradigm!
thoughtful separation of functions into distributed
and centralized
25 Copyright © 2014 Juniper Networks, Inc. www.juniper.net
CONCLUSION: THE SDN PARADIGM
The paradigm of SDN as a Network Operating System to form the basis for network programming is too low-level
§ This attacks the problem of new control plane implementations § Worthwhile problem for some, but not for all
The paradigm of SDN as a Compiler for provisioning via abstract service models is a high-level, declarative approach
§ This attacks the problem of service provisioning § Real problem for most who provide and manage network services
This paradigm is standards-based while allowing for provider-specific enhancements
This paradigm applies to all parts of the network: DC, inter-DC, access, edge, NFV, core
Recommended