Cloud Multicast Latency Limitation

The biggest current limitation with cloud providers when it comes to exchange tech is the lack of real multicast support. It is rare outside of exchanges, but extremely low latency L1 multicast market data has become the backbone of exchanges, both for fairness and for scalability. Knowing you can saturate your entire network with 10G traffic and every participant will get the same market data packets at the same time[0], and there will be zero queuing or bottlenecks is very hard to do otherwise. There is a pretty good podcast episode about it out of Jane Street[1]. I know AWS have 'multicast support' but last time I tested it, it was clearly just uni-cast traffic with a software switch doing fan-out/copying, I assume using the same tech as their transit gateway, I think it was called hyperplane or something. [0]: for some definition of the same time, at least low enough that you can't measure it without equidistant optical splitters or White Rabbit synced devices.

A screenshot presents a dense technical discussion about multicast market data, cloud providers, AWS, and ultra-low-latency exchange infrastructure. The joke is the extreme precision and absurdly demanding standard for “the same time,” requiring equidistant optical splitters or White Rabbit-synced devices. It is used as a reaction to overengineered systems, niche technology debates, or excessive low-latency optimization.

• @jemalloc / 1556 2024-04-16