SDN for Network Operators

Víctor López Core Network Evolution Global CTO Unit

SDN for Network Operators

2 Core Network Evolution Telefónica I+D, Global CTO

Index

Cloud-Ready Transport Networks 01

02

03

04

The SDN Concept

SDN for Network Operators

Concluding Remarks

01 Cloud-Ready Transport Networks


Cloud-ready Transport Network Approach

Photonic control plane GMPLS + PCE

Multilayer Coordination IP/MPLS Network

Routing, monitoring and automated IP configuration

Routing, monitoring and automated Photonic network configuration

Signalling

Optical Network

Cloud services Cross-S

tratum O

ptimization

Horizontal and Vertical Orchestration

Flexible Transport Network

Cross-Stratum

O

ptimization

L. M. Contreras, et all: “Towards Cloud-Ready Transport Networks”, in IEEE Communications Magazine, September 2012, Vol. 50, Issue. 9, pp. 48 - 55.


Mobile and Fixed Access Networks

IP Forwarding

§ The target is an E2E network able to perform automated connectivity control between end users and cloud data centers

§ This innovative network model aims to: ü  Accelerate service provisioning and performance monitoring ü  Enable on-demand connectivity configurations (e.g

bandwidth) by end users

ü  Optimize both cloud costs and power consumption ü  Guarantee the required QoS/QoE (…) for real time and

video services Network Control Flexible Transport

Network

Cloud Ready Networks rely on two main technological pillars

E2E MPLS photonic network

E2E MPLS

OPTICAL TRANSPORT

CPE

IP control and resource allocation (e.g IP v6)

Flexible transport network

Network-Cloud interface: new services development

Cloud Services

Network-Control

API

Resource Mngmt

Elasticity & QoS

Capacity

Leverage of

Cloud-ready Network Approach


Internet Voice CDN Cloud Business Service Management Systems

Network Provisioning Systems

Metro NMS

NMS Vendor A

IP Core NMS

Optical Transport NMSs

Collection of Umbrella Systems (see next)

Complex and long workflows for network provisioning over different segments (metro, IP core, Optical transport) requiring multiple configurations over different NMS

NMS Vendor B

NMS Vendor C

NMS Vendor D

NMS Vendor E

NMS Vendor C

NMS Vendor A

NMS Vendor B

Metro Node

Vendor A

Metro Node

Vendor B

IP Node

Vendor C

IP Node

Vendor D

IP Node

Vendor E

Optical Node

Vendor A

Optical Node

Vendor B

Optical Node

Vendor C

Core Network Nodes

CURRENT APPROACH FOR NETWORK PROVISIONING

Traditional core/backbone network operation is very complex and expensive •  Core network operation is not adapted to flexible networking

§  Multiple manual configuration actions are needed in core network nodes §  Network solutions from different vendors typically use particularized Network

Management System (NMS) implementations §  Very long service provisioning times


Now… Really complex

•  Example: Telefonica Spain has 269 management systems and 795 interactions

•  Plenty of Proprietary interfaces


Souce: Gartner (2012)

Cloud Computing – Hype Cycle


Inter-data center traffic

•  Standard cloud migration process in companies:

1.  Virtualization

2.  Private cloud

3.  Hybrid cloud

Hipervisor

VM VM VM VM VM

Hipervisor

VM VM VM VM VM Service Service

Autoprovisioning

Hipervisor


Autoprovisioning

Hipervisor


Autoprovisioning

Secure VPN


Hybrid Cloud Computing - Elasticity

•  Traditional IT and network dimensioning yields to this situations:

•  The network and the cloud must adapt to the end users requirements.

Capacity

t

Res

ourc

es

Res

ourc

es

Capacity

t

Capacity

t

Res

ourc

es

Under-provisioning Over-provisioning


Cloud Computing imposes new needs to fit by network providers

•  Services hosted in datacenters spread at the network border

•  Extremely high temporal bandwidth variability is shown in cloud traffic demand

•  Strong need for high-capacity and ultra-long haul datacenter interconnection

•  Service experience in cloud must be equivalent to the one perceived locally

Source: “Towards predictable DC networks”, SIGCOMM, 2011

1Gbps

100Mbps

Source: Amazon EC2 performance (http://bit.ly/48Wui)

Impact on two main network axis: Capacity and Elasticity


The Vision

To cope with quick changes and uncertainty

Mouldable infrastructures

To understand changes inside-out and be able to decide in real time

Insight capabilities

To adapt our offer to users necessities

User-centric connectivity experience

A network that delivers the best connectivity experience in an efficient and flexible way

02 The SDN Concept


Software Defined Networking

Network equipment as Black boxes

Open interfaces (OpenFlow) for instructing the boxes what to do

SDN

Boxes with autonomous behaviour Decisions are taken out of the box

FEATURE FEATURE

OPERATING SYSTEM

SPECIALIZED PACKET FORWARDING HARDWARE FEATURE FEATURE

OPERATING SYSTEM

SPECIALIZED PACKET FORWARDING HARDWARE

FEATURE FEATURE

OPERATING SYSTEM

SPECIALIZED PACKET FORWARDING HARDWARE FEATURE FEATURE

OPERATING SYSTEM


SDN

Adapting OSS to manage black boxes Simpler OSS to manage the SDN controller

SDN FEATUR

E FEATUR

E OPERATING SYSTEM

SPECIALIZED PACKET FORWARDING HARDWARE FEATUR

E FEATUR

E OPERATING SYSTEM


FEATURE

FEATURE

OPERATING SYSTEM

SPECIALIZED PACKET FORWARDING HARDWARE FEATUR

E FEATUR

E OPERATING SYSTEM



The Ossified Network

•  Many complex functions baked into the infrastructure

•  OSPF, BGP, multicast, differentiated services §  Traffic Engineering,

NAT, firewalls, MPLS, redundant layers, …

•  An industry with a “mainframe-mentality”, reluctant to change

15


Extracting Simplicity vs Mastering Complexity


Out of the Boxes

•  The network does not need to be seen any longer as a composition of individual elements

•  User applications interact with the network controller(s)

•  The network becomes a single entity §  Suitable to be programmed §  Aligned with current IT practices

•  We can apply different levels of abstraction §  Think of a network design flow §  And even an IDE

FEATURE FEATURE

OPERATING SYSTEM


FEATURE FEATURE

OPERATING SYSTEM


FEATURE FEATURE

OPERATING SYSTEM


FEATURE FEATURE

OPERATING SYSTEM



SDN Principles

•  Make network behaviour programmable §  Beyond individual boxes •  Fully decouple data and control planes §  Simple packet processing elements

(switches) §  Software-based controlling components

(controllers) •  Functions are split between per-packet

rules on the switch and high-level decisions at the controller •  Open interface between control and data plane •  Open interface to the control plane

•  Controllers actually program the network §  Even bypassing conventional layered

protocols and their configuration Switch"

Switch"

Switch "

Switch"

Switch"

SDN Control Plane Software!

."

App"

App"

App"

App"


The SDN Ocean

Are we creating a new set of protocols?


Infrastructure Layer (e.g DataCenter)

Basic SDN Approach for OpenFlow Domains

SDN Controller

ALTO SDN orchestrator

Application Layer

OAM Handler

TED VNTM PCE

Provisioning Manager

OPENFLOW

SDN CONTROLLER

API

OpenFlow is based on the concept of actions that are applied to each packet of a given flow (Ethernet-level addresses, VLAN tags, IP addresses, MPLS labels or transport-level ports). The actions taken by SDN the controller comprise: inserting and removing tags (layer 2), performing routing (layer 3) and also providing differentiated treatment to packets (QoS) •  We can not have a centralized entity to configure all network devices.

•  We need controllers which can talk each other. Is this another control plane?

03 SDN for Network Operators


Which architecture fits in a Network Network Operators?

SDN CONTROLLER

Big black box controlling the network

Centralize functionalities to enable automation

Define simple standard interfaces


Internet Voice CDN Cloud Business

Multiservice network provisioning system (SDN Orchestrator)

Standard signaling mechanisms running over network nodes enabling flexible networking and automated network provisioning over different network segments (metro, core IP, optical transport) including multiple vendors

Metro Node

Vendor A

Metro Node

Vendor B

IP Node

Vendor C

IP Node

Vendor D

IP Node

Vendor E

Optical Node

Vendor A

Optical Node

Vendor B

Optical Node

Vendor C

Service Management Systems

Network Provisioning

Core Network Nodes

Network-Service API

Network configuration interface

The path towards a unified network provisioning architecture •  Path towards a unified network provisioning architecture

§  Multiservice provisioning over pseudowires §  Automated multidomain/vendor/layer operation by signaling •  Key building block of such unified network provisioning architecture are: §  Network configuration interface: Multivendor edge nodes configuration (e.g OLT and BRAS,

IP core routers, etc) by standard interfaces (e.g OpenFlow) §  IT and network SDN orchestration: Coordinated network and datacenter resources control

according to service requirements (e.g orchestrated Virtual Machine transfer among datacenters)

§  Network-Service API: Application level API hiding details of the network


SDN controller definition

•  NBI Interface to interface applications

•  SBI with three main functionalities: §  Discover network resources

•  Example: IGP, BGP-LS, etc. §  Provision the request

•  Ej: OF, PCEP, NetConf, etc. §  Monitor the network.

Physical Network

Discovery Provisioning Monitoring

North Bound Interface

SDN Controller

GUI/NMS/Application

P. Pan, IPOP 2012


E2E networks might be pure OpenFlow based one day, but the migration process will take some time

Main actions to be taken by the SDN controller in E2E networks 1.  Discovery of network resources

2.  Routing, path computation

3.  Automated network orchestration in response to changing network conditions and service requirements

4.  Network resources abstraction to application layer

5.  QoS control and performance monitoring

6.  Multilayer interworking

7.  Multidomain/multivendor network resources provisioning through different control domains (e.g OpenFlow DataCenter, OpenFlow MAN, GMPLS optical transport…)


OpenFLow

Data Center

SDN controller based on IETF building blocks

SDN Controller

4- ALTO 3- ABNO controller

Applications (Internet, CDN, cloud…)

5- OAM Handler

1- Topo Mod 2- PCE 6- VNTM

7- Provisioning Manager

OpenFlow

MAN Domain

IP/MPLS core

OpenFlow Op7cal Domain

OPENFLOW

OPENFLOW

GMPLS Op7cal Domains

NETCONF

MPLS MAN

PCEP OPENFLOW CLI

D. King, et al. “A PCE-based Architecture for Application-based Network Operations”, draft-farrkingel-pce-abno-architecture-06


Topology Module •  Topology module has two main functions:

§  Import the network state §  Export topologicla information to lements like PCE, VNTM or ALTO.

Topology Module

Web Service

Topology Updater

Information Retriever

Topology Database

Transport View

IP View

Interlayer View Unique Topology Database

VNTM

ALTO Server XML Parser

BGP-LS

OSPF

PCE

Network Elements

Adapters

O. Gonzalez de Dios, V. López, C. Haya, C. Liou, P. Pan, G. Grammel, J. Antich, J.P. Fernández-Palacios: Traffic Engineering Database dissemination for Multi-layer SDN orchestration, in European Conference on Optical Communication (ECOC), Mo.4.E.2, Sep 2013.

04 Concluding Remarks


Video and cloud computing demands are stressing the network

SDN can help to define abstract interfaces for services thus reducing NMS complexity

1

2

3

Flexible technologies are mandatory in transport network evolution

4

Horizontal and vertical orchestration allows an automatic network provisioning of network services in layered networks

5 SDN can not be a big black box, thus standard building blocks and interfaces are required and SDN should delegate functionalities to control plane

Key messages


SDN for Network Operators

Technology

network border

e2e network able

main network axis

network providers services

network dimensioning

innovative network model

vendor b vendor c6

cloud costs