Question 1 of 250 from exam 400-201: Cisco CCIE Service Provider Written Exam

Question 1 of 250 from exam 400-201: Cisco CCIE Service Provider Written Exam

Question

Which Cisco IOS XR Virtualization technology provides full isolation between virtualized routing instances for extra control plane resources?

Answers

Explanations

A. B. C. D.

B.

References:

The Cisco IOS XR operating system is designed for high-end carrier-grade routers, which need to provide high availability, reliability, and scalability. One of the key features of IOS XR is its support for virtualization, which allows multiple routing instances to run simultaneously on a single router hardware.

There are several virtualization technologies available in IOS XR, each with its own benefits and use cases. In this question, we are asked to identify the technology that provides full isolation between virtualized routing instances for extra control plane resources. The answer is B. SDR, or Service Discovery and Redundancy.

SDR is a technology that allows a single physical router to be divided into multiple virtual routers, each with its own control plane and data plane resources. Each SDR instance has its own CPU, memory, interfaces, and software stack, which are completely isolated from other SDR instances on the same router. This means that a failure or misconfiguration in one SDR instance will not affect other instances, providing an extra layer of fault tolerance and security.

SDR is particularly useful for service providers who need to offer multiple services with different requirements on the same physical router. For example, one SDR instance could be dedicated to core routing and forwarding functions, while another instance could be dedicated to MPLS VPN services. Each instance can be configured and managed independently, providing greater flexibility and control over the network.

In summary, SDR is a virtualization technology in Cisco IOS XR that provides full isolation between virtualized routing instances for extra control plane resources. It allows a single physical router to be divided into multiple virtual routers, each with its own resources and software stack, providing greater flexibility, fault tolerance, and security.