CONFIGURATION.md

Configuration Reference

All implementations share the same set of configurable values. Each implementation exposes these through its own idiomatic API — see the configuration reference in the relevant subdirectory for details.

Socket / Buffer

Setting	Default	Description
Buffer size	65535	UDP receive buffer size and internal receive buffer capacity in bytes
Buffer pool initial size	16	Initial number of pre-allocated buffers in the pool
Buffer pool max size	64	Maximum pool size before buffers are discarded on return
Enforce buffer size	true	Drop datagrams that fill the receive buffer exactly, treating them as likely truncated

Relay

Setting	Default	Description
Relay port	7777	UDP port the relay binds to
Cleanup interval	5000ms	How often stale sessions and connections are evicted
Client timeout	15000ms	How long since last activity before a peer is considered stale
Main loop sleep	1ms	Sleep between relay processing loop iterations
Max pending connections	64	Max clients simultaneously in the connection handshake queue
Max rate limiters	1024	Max number of per-source rate limiter instances; cleared entirely when exceeded
Max packets per second	100	Per-source packet rate limit; excess packets are dropped
Max clients per session	32	Maximum connected clients per session, not counting the host

Host

Setting	Default	Description
ACK timeout	2000ms	How long to wait for a SESSION_CONFIG ACK before retransmitting
Max ACK retries	5	Max SESSION_CONFIG retransmit attempts before giving up
Session token timeout	300000ms	Reconnect token validity window — 5 minutes
Graceful shutdown timeout	3000ms	How long stop() waits for pending ACKs to drain
Processing loop sleep	10ms	Sleep between host processing loop iterations
Session tick rate	60	Tick rate advertised to clients in SESSION_CONFIG
Session max packet size	1200	Max game packet size advertised in SESSION_CONFIG in bytes

Client

Setting	Default	Description
Connection timeout	5000ms	Max time to wait for CONNECT_ACCEPT during handshake
Ping interval	5000ms	How often to send an auto-ping when the loop is running
Initial reconnect delay	1000ms	Initial backoff delay between reconnect attempts
Max reconnect delay	30000ms	Maximum backoff delay between reconnect attempts
Max reconnect attempts	6	Max reconnect attempts before giving up
Processing loop sleep	10ms	Sleep between client processing loop iterations

DTLS

Setting	Default	Description
DTLS context	null (disabled)	When set, a DTLS handshake is performed before any Neon packets are exchanged. The relay requires a server context (with a private key); hosts and clients require a client context (with a trust store). These should not share the same context instance.

Reliable Packet Manager

Setting	Default	Description
Reliable packet timeout	2000ms	Per-packet ACK timeout before retransmit
Reliable packet max retries	5	Max retransmit attempts before delivery failure is reported

Common Configurations

High-frequency action game (20ms tick)

• Host tick rate: 50
• Max packet size: 512
• Host and client loop sleep: 5ms
• Ping interval: 2000ms

Small LAN relay (trusted network)

• Relay port: 9999
• Max packets per second: 10000
• Max clients per session: 8
• Client timeout: 60000ms

Slow mobile connection with aggressive reconnect

• Connection timeout: 10000ms
• Initial reconnect delay: 500ms
• Max reconnect attempts: 10
• Session token timeout: 600000ms (10 minutes)
• ACK timeout: 5000ms