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NetCoreServer
Ultra fast and low latency asynchronous socket server & client C# .NET Core library with support TCP, SSL, UDP, HTTP, HTTPS, WebSocket protocols and 10K connections problem solution
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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
The tricky part is finding libraries that support multicast - most games don't use it. I found this though: https://chronoxor.github.io/NetCoreServer/
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