Manodipto Ghose
Product Manager Expert, ISG/NTS-L2/3

How to Keep Your Core Routers Ahead of the Expanding Internet

July 25, 2019 by Manodipto Ghose

The number of IP prefixes in the internet are increasing at an exponential rate. The size of the internet route table is stretching every day. A look at the classless inter-domain routing (CIDR) data of active border gateway protocol (BGP) entries (forwarding information base) indicates the day is not far that it will skyrocket beyond the 1 million mark. The BGP Routing table (RIB) has reached 10+ million with multi-path routes advertised by multiple BGP peering. This means the core routers must not only live up to the expectations of today but must gear up and scale to significantly higher numbers.


Figure 1: Source

Carriers are setting their goals of multi-million routes as a criterion for router vendor selection. Network equipment manufacturers (NEMs) must test this capability well in advance of entering the competitive market of carriers. The Carriers should validate with their network-specific scale and route matrix before deploying into production network. 

Testing is critical at each phase of network integration. It’s not just about pumping routes to the device under test. It is extremely important to test with real network traffic over these routes. The ability to test with line-rate traffic at various speeds is key to success. With soaring Ethernet speeds of 100GE and early adoption of 400GE picking up, it is critical to test traffic at scale with a real-world profile of millions of routes.

For decades, Ixia has been developing products for testing network infrastructure. IxNetwork has the capabilities to scale control plane traffic using advanced protocol emulations. A full suite of protocols starting with access and routing, and more recent technologies like segment routing, SDN has enabled NEMS, cloud providers, data center operators to ensure complete test coverage before going to production. 

Now, IxNetwork 9.00 supports massive scale of many millions of routes imported from a real-life internet tables in a single session. IxNetwork can read the routes from a file including the route prefix, AS path, next hop, and local preference information. Users can scale beyond 10M routes in a single session to bring up a complex control plane and also send traffic to the full set of routes using Ixia’s leading-edge hardware like Novus QSFP28 100/50/40/25/10GE Load Modules and AresONE 400GE fixed chassis. Enhanced user defined field (UDF) scalability enables customers to create more than 10M unique flows in IxNetwork traffic. This is an almost 10x improvement in scale from previous versions.


IxNetwork offers users both IPv4 and IPv6 Route import capability on multiple BGP peers, both in round robin and replicate manners. Users also have granular control over each prefix they have imported and override values in the route file. Protocol actions like “Age out routes” and “Readvertise routes” are critical while debugging issues with a real-world test scenario. IxNetwork supports popular formats of router vendors for conveniently using routes captured from a production core router and simulating such scenarios through the application in a lab environment. 
In summary, with the growing need to scale the internet route table, the need for testing ahead of today’s scale for network infrastructure is compelling and IxNetwork is ready for today and any future needs in this area.

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