> > On 4 Dec 2019, at 18:56, Rod Beck <rod.b...@unitedcablecompany.com > <mailto:rod.b...@unitedcablecompany.com>> wrote: > > Can someone explain what is all the fuss? SDN is like the latest telecom > craze but the articles do a poor job of explaining the advantages. I seek > concrete examples.
Maybe our example from my Fiberhood.nl <http://fiberhood.nl/> company can illustrate. It is the size of two PhD projects in our small research institute spun of as a neighbourhood ISP and smart microgrid. We needed a way to build our wide area network (an internet access provider) AND a supercomputer interconnect to both allow for loops in the network. None of the standard switches like Cisco and Juniper can handle this gracefully. SDN/Openflow, especially P4, allows us to write a few programs in a few weeks that generates the hardware and software for the 120 Gbps and 6 terabit mesh switches for whatever topology of our network. We can buy white label switches for $5000 or our own $800 12x10G FPGA fabric switches or $1000 260x50 Gbps switches. We save a few million in an fiber ISP metro network to 20.000 households with 4x10 Gbps ports. More important, we don’t have to fight (adapt and patch) Cicso and Juniper legacy software and protocols every week for 10 years on switches costing 20 times as much. We can test all our software before we built in mininet in an afternoon on a laptop. We could build a test network with OpenVswitch in on fast off the shelf linux servers with 10G ports. We found the Slimfly topology to be $2000 cheaper per household than all other switch topologies. My ISP WAN network winds up being almost as fast as Cray + AMD new Rome zen 2 supercomputer cluster switch fabric with the investment of three people while saving $2000 per location and a few million in my core datacenters with our own hardware product (similar to a NetFPGA Sume https://netfpga.org/site/#/ <https://netfpga.org/site/#/> with 2000 in use). We moved an academic network out of the lab into a fiber ISP Wan for less than $200.000 while saving $40,000,000. A side effect of building arbitrary topologies is an additional saving of $4,000,000 in cable lengths in a 4km2 naighmerhood fiber rollout. Cheers Merik Voswinkel, Fiberhood Coop Metamorph research institute
