Imagine you want to have an IPv6-only access network and transport residual IPv4 traffic tunneled across it. Sounds great, but you need to terminate those tunnels and encapsulate/decapsulate IPv4 traffic at multi-gigabit rate.
There are plenty of reassuringly-expensive hardware solutions that can do that, or you could work with really smart people and get software-based solution that can do 20 Gbps per CPU core.
In Episode 52 of Software Gone Wild David Gee and myself spoke with Katerina Barone-Adesi from Igalia, an interesting open source consultancy company. Their networking team wrote highly optimized software that runs on Snabb Switch and delivers the amazing above-mentioned performance.
Interested? Listen to the podcast, and watch the video of Katerina presenting her solution at FOSDEM 2016 (it may not play in every browser; the slides are here).
You might also want to listen to other podcasts we mentioned:
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