12-07-2013, 04:00 PM
Network Virtualization
Network Virtualization.ppt (Size: 857 KB / Downloads: 180)
Introduction
Motivation for network virtualization
Deployment dilemma, too many design goals, and coordination constraint
Pluralist networks
Economic refactoring
Infrastructure and service providers
Research challenges
Systems challenges
Resource allocation
The Internet: A Remarkable Story
Tremendous success
From research experiment to global communications infrastructure
The brilliance of under-specifying
Best-effort packet delivery service
Key functionality at programmable end hosts
Enabled massive growth and innovation
Ease of adding hosts and link technologies
Ease of adding services (Web, P2P, VoIP, …)
But, change is easy only at the edge…
Rethinking the Network Architecture
But, the Internet is showing signs of age
Security, mobility, availability, manageability, …
Challenges rooted in early design decisions
Weak notion of identity, tying address & location
Not just a matter of redesigning a single protocol
Revisit definition and placement of function
What are the types of nodes in the system?
What are their powers and limitations?
What information do they exchange?
Overcoming the Hurdles
Deployment Dilemma
Run multiple experimental networks in parallel
Some are mature, offering services to users
Isolated from others that are works in progress
Too Many Design Goals
Run multiple operational networks in parallel
Customized to certain applications and users
Coordination Constraint
Run multiple end-to-end services in parallel
Over equipment owned by different parties
Ways to Exploit Router Virtualization
Exploiting the new capabilities in routers
Separation of the physical from the logical
Ability to run multiple routers in parallel
Example: virtual router migration
Moving router from one physical node to another
E.g., for planned maintenance or service roll-out
Example: bug-tolerant routers
Running multiple instances of routing software
… and “voting” to protect the system from bugs