Hello, and welcome to my blog. As a new member of the Enterprise Networking’s Solutions Marketing team, I’ll be writing about connectivity to the cloud, Software Defined Networking (SDN) and virtualized routing. You can expect to learn details around Cisco’s architecture and product offerings in these topics. Further, based on your comments, I can go into as much detail as necessary.

First, a brief background. I moved to the Bay Area last November from Boston after almost 20 years in New England (in Boston), so I will be musing about culture shocks between the two coasts. I may also learn to like the Warriors and Niners, but I will always be a Celtics and Patriots fan.

Second, a promise I make. One of my favorite authors, Mark Twain/Samuel Clemens wrote in a letter to a friend in 1880 “I notice that you use plain, simple language, short words and brief sentences. That is the way to write English – it is the modern way and the best way. Stick to it; don’t let fluff and flowers and verbosity creep in” My promise is that I will try my best to adhere to this standard of writing, especially for such a technology focused blog. If I let any fluff and flowers in, please let me know in the comments and I will make it up to you.

With that, let’s jump into our first topic: The virtualization of routing. Specifically, the Cloud Services Router 1000V (CSR 1000V), which was announced at Cisco Live-San Diego on June 12, 2012.

CSR 1000V: Evolution of virtualized routing

While a previous blog covered the introduction of the CSR, I am happy to report that the CSR 1000V is now in general availability, starting March 29, 2012, a significant milestone for Cisco and for virtualization of full-fledged routing in general. After extensive field trials with 50+ customers, the CSR is being deployed in production networks across enterprises and cloud service providers around the world.


  • In the GA release CSR is a full-fledged secure virtual router, with IOS-XE routing, NAT, DHCP, IPSec, DMVPN, FlexVPN, HSRP, AppNav, FireWall, MPLS, LISP, Multicast, L2TP, QoS, NetFlow, AVC, Full IPv6. It runs on VMware ESXi.
  • Support for VXLAN and GETVPN is coming soon.


  • Runs in VMware vSphere Ent. (vMotion, DRS)
  • Support for Citrix XenCenter, and Red Hat KVM is coming soon


  • 4-vCPU/4GB @ 10/25/50 Mbps
  • Higher throughput options are coming soon


  • Cisco Prime NCS, VMware vCenter, vCloud Director


  • Currently offered with term-based licensing for 1, 3, 5 year licenses
  • Other flavors of licensing are coming soon

CSR 1000V and next generation virtualized routing

CSR 1000V offers cloud service providers an unprecedented scalability option to host multiple tenants while delivering differentiated services tailored to each tenant. By creating a full-fledged virtual routing infrastructure to complement the physical infrastructure, the CSR 1000V and other Cisco virtualized services products enable a 10x scaling capability for cloud service providers. Where they could only host 250 tenants per pod, cloud service providers can now host up to 2500 tenants with the same exact physical infrastructure by adding the CSR 1000V.  This picture shows a typical deployment at a cloud service provider with the CSR 1000V operating as virtual infrastructure.

Virtual networking and cloud services

Combined with the Cisco Nexus 1000V virtual switch, the CSR 1000V offers a full-fledged routing and integrated services architecture. CSR 1000V has Cisco AppNav built in, which allows load balancing across virtual WAAS devices (Cisco vWAAS). When connected to the Cisco Nexus 1000V through Cisco vPath, the service applies security policies at Cisco Virtual Security Gateway VSG and the Cisco ASA 1000V Cloud Firewall. This allows a complete service chaining in the virtual infrastructure at the cloud service provider and more importantly, on a per tenant basis.

CSR as an MPLS CE Router:

A specific use case for the CSR 1000V is that it can be deployed as an MPLS Customer Edge (CE) router. With a typical (non-virtualized) deployment, a cloud service provider’s PE router acts as a MPLS tunnel termination point, which then funnels per-tunnel traffic into VRF instances (with iBGP and eBGP peering) which are then mapped to L2 VLANs. Normally, the cloud service provider would have to allocate a VLAN at the PE and carry that all the way through to the server aggregation switches. With a single PE router limited to 4000 VLANs and even less VRF instances and BGP sessions (typically to 1000 BGP peers), the number of tenants is limited to around 250. (The detailed network topology and BGP peering numbers have been calculated in a technical paper).

With the CSR 1000V, a cloud service provider can now terminate the MPLS tunnels of tenants at the CSR 1000V in the virtual infrastructure and not be limited by the VRF and BGP scaling limitations of the physical infrastructure (PE router and Aggregation switches). This picture shows the deployment of a CSR as a MPLD CE router and how a cloud service provider can overcome the VLAN and other scalability limits.MPLS Customer Edge Router

Cloud service providers who have seen this in action are excited by the results of the EFT deployments.

For additional validation, here is a Network World test of CSR in action.

What’s next:

In the next few blogs I’ll cover additional aspects of virtualization of routing, including the architectural and product perspective.

  • CSR 1000V and virtualization of services (vWAAS, AppNav and vPath)
  • Other use cases for the CSR 1000V
  • SDN and CSR 1000V: Cisco ONE strategy’s Virtual Overlays pillar and how the onePK API can provide programmability to the CSR 1000V
  • I just hosted a webinar with Ovum titled “How to choose a cloud service provider?” where we discuss the various factors to consider, especially the virtual infrastructure, when selecting a cloud service provider to host your virtual private cloud. Please see the recording here.

Thanks for reading and please comment on any and all aspects. I look forward to your comments. Stay tuned for the next blog post.


Satish Katpally

Senior Marketing Manager

Application Centric Infrastructure, SDN, ONE Software Suites