Virtual Routing and Switching
Virtual Routing (VR) logically subdivides a physical router into multiple virtual routers, and allows each virtual router to execute separate instances of the routing protocol and the network management software, for example, SNMP or CLI. Each virtual router can be independently monitored and managed by the user. Many sources refer to virtual routers in terms of their application within virtual private networks (VPNs). This design interprets the VPN implementation to be a specific application of the overall virtual routing design. As a result, the VPN approach is considered to be an add-on feature of virtual routing.
The ZebOS® Advanced Routing Suite offers optional Virtual Routing (VR) support for both the IPv4 and IPv6 routing protocol modules. Virtual routing provides support for multiple Routing Information Bases (RIBs) and multiple Forwarding Information Bases (FIBs) per physical router. Each VR consists of an OSPFv2, BGP- 4(+), or RIP Protocol, each with its own Route Information Base (RIB) and Forwarding Information Base (FIB).
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Virtual Routing and Switching
In addition, the following IPv4 and IPv6 multicast protocol modules support Virtual Routing: Protocol Independent Multicast-Sparse Mode (PIM-SM and PIM-SMv6), and Protocol Independent Multicast-Dense Mode (PIM-DM and PIM-DMv6).
Virtual routing’s ability to provide the appearance of multiple individual machines on a single physical platform is a vital tool in the toolbox of service (and content) providers in meeting the demands of NGN markets.
Virtual routing supports the separation of services by:
- Content Providers – Content providers have different requirements for network resources, with each provider having a unique set of characteristics. Some content has the potential to disrupt other traffic on the network. Assigning a separate VR to a content provider allows for the ability to tune that VR to the specifics of expected traffic.
- Services – Services may also be segregated by VR, taking maximum effect from efficiencies of scale that are provided by generalizing service-specific components across large numbers of subscribers.
- Subscribers – Some network demands are best addressed by providing a VR on a per-subscriber basis. This approach helps to maintain data integrity and security for the subscriber and protect them from malicious access attempts that originate in the external network
Benefits of Virtual Routing and Switching
- Each virtual router (VR) can be independently managed and monitored by the user
- Provides the appearance of multiple individual machines without the expense of additional equipment
- Supports the separation of services for content providers, services and subscribers
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