Micro Socket Methodology

What is Micro Socket?

Micro Socket brings the microservice mindset to sockets and real-time communication.

• Server: A sub-socket (subscription group) per topic/channel; millions of concurrent broadcasts.
• Client: Multiple micro socket connections; each with a single responsibility (one topic or QoS).
• Global: Distributed gateways, same invariants and protocol for consistent handling of socket issues.

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Principles

Principle	Description
Single responsibility (per socket)	Each micro socket serves one topic, one QoS, or one workflow.
Invariants never break	I₁–I₇: ACL, dedup, ordering, delivery, SLO, resume, integrity.
Scale unit: sub-socket	Server can open millions of sub-sockets; lightweight and isolated.
Client is micro too	Client can use multiple micro sockets (e.g. price / risk / payment).
Same behavior globally	Same protocol and guarantees regardless of region or gateway.

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Global Problems and Solutions

Problem	Micro Socket solution
Millions of connections on one server	Sub-socket + gateway cluster for isolation and load spread.
Geographic latency	Distributed gateways; same invariants in every region.
Duplicate processing	I₂: dedup via messageId/idempotencyKey (gateway + backbone).
Loss after disconnect	I₆: RESUME + sessionId + lastSeq; gap replay.
Unauthorized access	I₁: ACL on SUBSCRIBE/PUBLISH.
Order violation	I₃: seqNo + single partition/stream.
Unmeasurable behavior	I₅: p50/p95/p99 SLO and test matrix.

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Implementation Steps (Summary)

1. Design: Define topics and QoS; define sub-socket boundaries.
2. Protocol: Identity, messageId, seqNo, QoS/ACK fields.
3. Gateway: ACL, dedup, ordering, resume logic; backbone integration.
4. Backbone: NATS/Kafka/Redis for at-least-once or exactly-once.
5. Client: SDK compatible with messageId/seqNo/RESUME.
6. Test: Double processing, ordering, latency, resume, ACL matrix.
7. SLO: Monitor p50/p95/p99 and resume success rate.

See Algorithms and Node.js Gateway for details.