roblox networking
When to Load
Load when adding a remote, handling untrusted client input, implementing cooldowns, or deciding which side owns a gameplay result.
Quick Reference
- Treat every client argument as attacker-controlled input.
- Validate type, size, ownership, state, distance, and cooldown on the server.
- Look up prices, damage, rewards, and permissions from server-owned definitions.
- Choose the authority model before designing movement or continuous simulation. Server Authority uses client input prediction and server rollback; it is not the same thing as handing a part to a client with
SetNetworkOwner. - For simulation-affecting input in Server Authority, use
InputAction/InputContextandRunService:BindToSimulation()(requiresWorkspace.UseFixedSimulationenabled in Studio) rather than feeding continuous input through aRemoteEvent. - Use events for most gameplay requests. Keep
RemoteFunctioncalls short and bounded. - Use
RemoteEventfor reliable state changes within its event channel. Do not assume a RemoteEvent is ordered with property or attribute replication; use one explicit state channel or version the state when ordering matters. UseUnreliableRemoteEventonly for replaceable or ephemeral data such as VFX and continuous snapshots. - Unreliable does not mean automatically faster: delivery is unordered, packets may be dropped, and payloads should stay at or below the documented 1000-byte limit.
- Measure payload size and fire rate under load. Do not treat a community packet-size estimator as an official wire-format specification.
- Validate numeric inputs for NaN and infinity (
x ~= x,math.abs(x) == math.huge) before range checks:NaNdefeats</>. Apply the same class of check to strings:utf8.len(s)returns nil for malformed UTF-8 that would fail a DataStore save. - Rate limits protect the server, but validation must still reject invalid requests.
- Record suspicious behavior and use thresholds. Do not punish a player for one malformed packet.
Need the details? Load references/full.md for reusable validation and throttling patterns.