Service providers and enterprises worldwide have deployed and utilized Border Gateway Protocol (BGP) for an increasing number of services like Internet peering, Layer 2/Layer 3 VPN, BGP Link State harvesting, and security policy propagation by BGP flow specification. However, scaling a large iBGP full-mesh peering requires optimizing the control plane architecture. BGP route reflection as defined in RFC 4456 has emerged to become the de facto choice for scaling full-mesh iBGP deployments.
Traditional route reflectors were deployed using either core routers or dedicated physical hardware solely for control plane route-reflection purposes. While this has proved to be a viable solution that meets the demands of BGP with all the CPU and memory required, it lacks the flexibility, elasticity, and agility to meet the frequently changing demands of the services.
Deploying a virtualized network function (VNF) in the form of a route reflector is proving to be the next logical evolution to address the shortcomings brought about by physical device limitations regarding elastic flexibility of device resources such as memory and CPU.
Introducing Cisco IOS® XRv—a virtual router that uses the same carrier-class Cisco IOS XR operating system powering the ASR 9000 and CRS series high-end routers since 2004. It provides the same key benefits as Cisco IOS XR while providing the elasticity, agility, and flexibility that a VNF brings.
To read the full white paper:
http://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/ios-xr-software/whitepaper-c11-731132.html
