export interface HeartbeatOptions {
    sendPing: () => void;
    onTimeout: () => void;
}
export declare class Heartbeat {
    private readonly _sendPing;
    private readonly _onTimeout;
    private _seenPacket;
    private _heartbeatIntervalHandle;
    private _heartbeatTimeoutHandle;
    static HEARTBEAT_INTERVAL: number;
    constructor(options: HeartbeatOptions);
    stop(): void;
    start(): void;
    private _startHeartbeatIntervalTimer;
    private _startHeartbeatTimeoutTimer;
    private _clearHeartbeatIntervalTimer;
    private _clearHeartbeatTimeoutTimer;
    private _heartbeatIntervalFired;
    private _heartbeatTimeoutFired;
    messageReceived(): void;
}