Network Virtualization – a view from the bottom

Jorge Carapinha, PT Inovação

Javier Jimenez, Telefonica I+D

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona

• Minimizing cost of ownership

• New revenues

– Reselling infrastructure to 3rd parties

– “Next-generation” managed services

• Flexible deployment of new technologies

Why NV matters to operators

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 2

• Technology diversity instead of “one size fits all”

solution (as advocated by today’s IP-based

convergence)

• From the user (VPN customer) standpoint, […] the VR [must] be as

equivalent to a physical router as possible. In other words, with very

minor and very few exceptions, the VR should appear for all purposes

(configuration, management, monitoring, troubleshooting) like a

dedicated physical router.

• A VR […] simply has to provide the illusion that a dedicated router is

available to satisfy the needs of the network(s) to which it is

NV 1st wave – Virtual Routers

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 3

available to satisfy the needs of the network(s) to which it is

connected.

[RFC2917 - A Core MPLS IP VPN Architecture, September 2000]

Building VR-based VPNs

VPN A

VPN A

VPN B

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 4

VPN A

VPN B

VPN C

VPN C

Virtual link

L3 VPN: RFC 4364 model (BGP/MPLS VPN)

VRF

VRF

VRF

VRF

CE

siteCE

site

MP-BGP

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 5

PE PEP

VRF VRF

CE

siteCE

site

customers VPN service providercustomers

P

Network Virtualisation – general overview

Virtual Network n

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 6

Physical network

Virtual Network 2

Virtual Network 1

4WARD Network Virtualisation business

model

Virtual Network

Virtual Network

Operator (VNO)

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 7

Virtual Network

Provider (VNP)

Physical

Infrastructure

Provider (InP)

Physical

Infrastructure

Provider (InP)

Physical

Infrastructure

Provider (InP)

Types of substrate nodes

Network domain

Other domains

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 8

Edge nodeCore VN-

capable node

Core transport

nodeBorder node

• Scalability

• Efficient and dynamic resource management

• Seamless VN / infrastructure separation

• Strict inter-VN isolation

Network Virtualisation key challenges

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 9

• Node scalability (# of VNs per physical node)

• Global architecture scalability

– State information maintained in core nodes

– Virtual link aggregation favours separation of

transport and virtualized nodes

– Trade-off between fine-grained resource control (VN

Scalability

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 10

– Trade-off between fine-grained resource control (VN

isolation) and link aggregation (scalability)

Resource management

aF

A

B

C

D E

F

G

Hl

A

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 11

Physical link

Virtual link

C

D

G

H

E

b

c

d

e

f

g

h

i

j

k

m

n

o

p

B

Seamless VN/infrastructure separation

Virtual Network

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 12

Physical Network 1 Physical Network 2

Virtual Network isolation

Virtual Network 1

Virtual Network 2

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 13

Physical network

Virtual Network 1

• Network virtualization is a promising concept for

operators in several contexts and scenarios

• VPNs can be seen as precursors of full-blown network

virtualization and should provide useful lessons

• Issues to be faced before network virtualization can be

deployed in large scale commercial scenarios

Conclusions

ACM SIGCOMM VISA’2009 Workshop, 17/08/09, Barcelona 14

deployed in large scale commercial scenarios

– Scalability

– Resource management

– VN / infrastructure separation

– VN isolation.