Mission Apollo: Landing Optical Circuit Switching at Datacenter Scale · HackerPapers discussions

Mission Apollo: Landing Optical Circuit Switching at Datacenter Scale — mentioned by crote

Tue, 03 Nov 2026 10:39:56 GMT

Google's OCS Apollo[0] achieved roughly the same losses and switching latency using MEMS, but with 136x136 connectivity. They expect it to scale beyond 1000x1000. What's the unique selling point for this new solution? Cost? Something quantum-related MEMS can't do? [0]: https://arxiv.org/abs/2208.10041

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Mission Apollo: Landing Optical Circuit Switching at Datacenter Scale — mentioned by jsolson

Wed, 10 Jun 2026 00:34:46 GMT

Then, if you want to know about using optical switches to connect Clos segments without a fixed spine, check out Google's "Mission Apollo" paper: https://arxiv.org/pdf/2208.10041

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Mission Apollo: Landing Optical Circuit Switching at Datacenter Scale — mentioned by cavisne

Sun, 01 Oct 2023 00:47:41 GMT

Correct, google also has a paper on this at the DC level https://arxiv.org/pdf/2208.10041.pdf

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Mission Apollo: Landing Optical Circuit Switching at Datacenter Scale — mentioned by rlupi

Sat, 08 Apr 2023 18:39:59 GMT

ICI is interchip interconnect in TPUv4 pods. You can read more on paper that my collegues in Google platforms recently published https://arxiv.org/abs/2304.01433 https://cloud.google.com/blog/topics/systems/tpu-v4-enables-... I am so happy this paper is finally out :-) I led the SRE work during their NPI. It's a pain when you have to wait 3 years to discuss what you worked on. They are based on OCS, which powers Google datacenter networks https://arxiv.org/abs/2208.10041

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Mission Apollo: Landing Optical Circuit Switching at Datacenter Scale — mentioned by sanxiyn

Wed, 05 Apr 2023 07:19:53 GMT

As the paper explains, optical circuit switches are not new in TPU v4 and not the main topic of this paper. Google was already using it for networking and published about it last year. For details, see https://arxiv.org/abs/2208.10041.

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