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Switches complete Avaya SDN suite

Stackables add access piece to Fx jigsaw

Too much control traffic, too little network

The model that underpins SDN is that the data plane and control plane are separated from each other, but once that stretches across the wide area, Claridge says, the control traffic becomes a significant burden equivalent to needing “a parallel network”.

“In a mobility world, everything is changing all the time. I need to get your applications to you, on the network, with the right services – everywhere you might be,” he explained.

“If I use OpenFlow – I'd be commanding the network to reconfigure itself all the time ... that doesn't optimise anything”.

While people are bedazzled by cheap switches built on merchant silicon, Avaya's pitch is that the real costs are in “operations – keeping the lights on", he said, and “at the end of the day, it's the plumbing that gets in the way".

Instead, he said, Avaya has modelled Fx SDN on “what the industry did with L3 and MPLS – we used BGP to signal control. [In SDN Fx] we've done the same using shortest path bridging, and IS-IS to do autonomous signalling in the network itself.

“We believe we've built an SDN model that allows the interior of the network to self-configure, to match ingress and egress endpoint requirements.”

At the same time – important for Internet of Things applications – the SDN Fx skips the VLAN limits at Layer 2.

“You can only have 4,000 VLANs in a switch, and most switches today are choking at about 2,000 VLANs,” he said, and in an IoT world, millions of paths may be needed.

In healthcare, for example, "I've now got thousands of new devices coming onto the network, and I can't group them into multiple VLANs because I run out".

SDN protocols have this advantage: the VLAN ceases to matter. “You can remap old numbers into a new service ID and you can have millions of these. You've removed the limitations that exist in being able to deploy an IoT model.” ®

Bootnote: A regrettable global-replace error on the author's part attributed the product to Alcatel-Lucent in the original version. My apologies to both companies.

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