Mellanox, Ixia and Cumulus: Part 2

This post is part two of three in a series looking at the joint presentations made by Mellanox, Ixia and Cumulus at Networking Field Day 17, in February 2018. More specifically, this post looks at what part Ixia has to play in the deployment of an Ethernet switch fabric built using Mellanox switches and running Cumulus Linux as the Network Operating System (NOS).

Cumulus/Mellanox/Ixia Logos


What confused me most about a presentation from Mellanox, Ixia and Cumulus about Ethernet fabrics was to figure out what role Ixia would be playing in the disaggregated model. Mellanox makes the switch hardware and Cumulus makes the switch software, so Ixia fits, well, where exactly?


IxNetwork is billed as an end-to-end validation solution which in many ways undersells what it’s all about. Rather than being just more traffic-generating test equipment, IxNetwork can emulate multiple switch and server devices so that a single piece of test hardware can be connected to what it believes is a large existing infrastructure, and that hardware’s behavior and resiliency can be validated. In the demo topology, IxNetwork connects to a physical Mellanox Spectrum switch running Cumulus Linux, emulating connected servers as well as an entire leaf/switch EVPN/VXLAN fabric, attached hosts and VTEPs, to which the physical switch can be connected.

Ixia Demo Topology

The emulated environment establishes EBGP connections to the Mellanox/Cumulus switch as it would in a real network. Additional clarity may be gained by looking at the same demo configuration in the Scenario tab of the IxNetwork UI:

Ixia GUI

Ixia’s IxNetwork allows one or more physical switches to be tested in the context of a fully emulated data center environment, validating packet loss, latency and similar statistics end-to-end, allowing captures to be taken at any point in the network, and so forth. IxNetwork can connect to interfaces ranging from 1Gbps to 400Gbps, so it’s definitely keeping pace with current hardware. This capability would be incredibly helpful if I were evaluating new hardware for my network, but for end users like me this seems like only an occasional need until a purchasing decision has been made.

There are two videos for Ixia; the first is an introduction to IxNetwork:

The second is the product demo itself:

Based on the presentations alone, I was trying to determine use cases for IxNetwork that would allow me to justify spending money on this test suite. Certainly if I were a switch vendor, I might appreciate the ability to prove my hardware’s capabilities. Similarly, if I were evaluating different vendor’s hardware as a potential new switching platform for my network, I’d be very interested to have this kind of emulated test environment to hand, as it would allow me to test the hardware as part of a larger environment where it’s running protocols and switching packets in the way it would do in a real network (e.g. EBGP and VXLAN); after all, pushing a stream of L2 frames through a switch at high speed does little to confirm how the switch copes if its also having to read VXLAN headers and make routing decisions for each frame/packet. These are, however, very limited use cases and potentially only transient in need, which would not encourage me to make the investment.

However, researching a little further it seems that IxNetwork goes beyond what was presented, offering emulation of routed networks for example, able to interface with physical equipment using a variety of IGPs (e.g. ISIS, OSPF, EIGRP and RIP), IGBP and EBGP (including FlowSpec). It can communicate using MPLS (supporting LDP and RSVP-TE) with L2VPN, L3VPN, Multicast VPN and more, and it can emulate PIM-SM/SSM and IGMP/MLD querier/receiver for multicast, and it supports LACP and BFD. It’s possible therefore to emulate a large, routed network, enterprise WAN or service provider WAN and see how connected equipment (or small sections of physical infrastructure) would behave and perform as part of the wider network rather than testing components in isolation. IxNetwork seems to combine complex multi-protocol network emulation with competent traffic generation capabilities


I appreciate seeing how IxNetwork can be used to validate the performance of the Mellanox/Cumulus switch combination. This does not, however, fill me with a need to invest in the Ixia product myself. However, I can see how service providers, for example, would be all over IxNetwork as a way to consistently test and validate things like Network Functions Virtualization (NFV), software-defined CEs and anything else which might need to be evaluated. I can imagine services being tested using IxNetwork purely as an emulated network in the service path to provide realistic testing and failure scenario outcomes. The relationship of IxNetwork to the Mellanox/Cumulus switch seems to be limited to validating that this combination of hardware and software performs well, as expected, and there is for sure some value in that.

To be fair to Ixia, I don’t think IxNetwork is a good fit what I currently do, so my gut reaction is not necessarily one of excitement. However, I can see how a product like this could be an every day tool in some environments, and could help improve the success of product deployments. With that in mind, IxNetwork gets a sincere ‘would definitely evaluate’ if I were in the market for a tool of this type.



I was an invited delegate to Network Field Day 17 at which all the companies listed above presented. Sponsors pay for presentation time in front of the NFD delegates, and in turn that money funds the delegates’ transport, accommodation and nutritional needs while there. With that said, I always want to make it clear that I don’t get paid anything to be there (I took vacation), and I’m under no obligation to write so much as a single word about any of the presenting companies, let alone write anything nice about them. If I have written about a sponsoring company, you can rest assured that I’m saying what I want to say and I’m writing it because I want to, not because I have to.

You can read more here if you would like.

1 Trackbacks & Pingbacks

  1. Mellanox, Ixia and Cumulus: Part 2 - Tech Field Day

Leave a Reply

Your email address will not be published.


This site uses Akismet to reduce spam. Learn how your comment data is processed.