/**
 * @file dcep.ts
 * @description Data Channel Establishment Protocol (RFC 8832) message codec.
 * @module sctp/dcep
 *
 * DCEP runs on PPID 50 and negotiates a data channel on an SCTP stream:
 *   DATA_CHANNEL_OPEN (0x03)  -> DATA_CHANNEL_ACK (0x02)
 */
export declare const MESSAGE_TYPE: Readonly<{
    DATA_CHANNEL_ACK: 2;
    DATA_CHANNEL_OPEN: 3;
}>;
export declare const CHANNEL_TYPE: Readonly<{
    RELIABLE: 0;
    RELIABLE_UNORDERED: 128;
    PARTIAL_RELIABLE_REXMIT: 1;
    PARTIAL_RELIABLE_REXMIT_UNORDERED: 129;
    PARTIAL_RELIABLE_TIMED: 2;
    PARTIAL_RELIABLE_TIMED_UNORDERED: 130;
}>;
export interface OpenParams {
    channelType: number;
    priority?: number;
    reliabilityParameter?: number;
    label?: string;
    protocol?: string;
}
export interface DecodedOpen {
    channelType: number;
    priority: number;
    reliabilityParameter: number;
    label: string;
    protocol: string;
    unordered: boolean;
}
/**
 * Encode a DATA_CHANNEL_OPEN message.
 * @param {Object} p
 * @param {number} p.channelType
 * @param {number} p.priority
 * @param {number} p.reliabilityParameter
 * @param {string} p.label
 * @param {string} p.protocol
 * @returns {Buffer}
 */
export declare function encodeOpen({ channelType, priority, reliabilityParameter, label, protocol }: OpenParams): Buffer;
/**
 * Decode a DATA_CHANNEL_OPEN message.
 * @param {Buffer} buf
 * @returns {Object}
 */
export declare function decodeOpen(buf: Buffer): DecodedOpen;
/** Encode a DATA_CHANNEL_ACK message. */
export declare function encodeAck(): Buffer;
/** Return the message type of a DCEP buffer. */
export declare function messageType(buf: Buffer): number;