In this document, the term Q.921-User refers to an upper layer which uses the services of Q.921, not the user side of ISDN interface [1]. Examples of the upper layer would be Q.931 and QSIG. 在本文件中，术语Q.921-用户是指使用Q.921服务的上层，而不是ISDN接口的用户端[1]。

In the integrated ISDN Layer 2/3 model (e.g., in traditional ISDN switches), it is assumed that the Layer Management for the Q.921 Layer and the Q.931 layer are co-located. When backhauling ISDN, this assumption is not necessarily valid.

Q.921 : ISDN user-network interface - Data link layer specification Recommendation Q.921 (09/97) Approved in 1997-09-12. Status : In force Table of Contents Summary . Access : Freely available items. Available languages and formats : Click on the selected format and language to get the document ...

ISDN user-network interface - Data link layer specification This Recommendation is also included but not published in I series under alias number I.441 Superseded

2001年2月1日 · This document defines a protocol for backhauling of ISDN Q.921 User messages over IP using the Stream Control Transmission Protocol (SCTP). This protocol would be used between a Signaling Gateway (SG) and Media Gateway Controller (MGC). It is assumed that the SG receives ISDN signaling over a standard ISDN interface.

2012年10月25日 · ITU-T Q.921/Amd.1 (06/2000) 1 . ITU-T Recommendation Q.921 . ISDN USER-NETWORK INTERFACE – DATA LINK LAYER SPECIFICATION . AMENDMENT 1 . 1) Clause 1 . Add a new paragraph to the scope as follows: Annex J of this Recommendation describes in general terms the link access procedure for use in a

2023年1月24日 · Integrated Services Digital Network (ISDN) Q.921-User Adaptation Layer. This document defines a protocol for backhauling of Integrated Services Digital Network (ISDN) Q.921 User messages over IP using the Stream Control Transmission Protocol (SCTP). This protocol would be used between a Signaling Gateway (SG) and Media Gateway Controller (MGC).

In this document, the term Q.921-User refers to an upper layer that uses the services of Q.921, not the user side of ISDN interface [1]. Examples of the upper layer would be Q.931 and QSIG.

本文件定义了使用流控制传输协议（SCTP）通过IP回传综合业务数字网（ISDN）Q.921用户消息的协议。 该协议将在信令网关（SG）和媒体网关控制器（MGC）之间使用。 假定SG通过标准ISDN接口接收ISDN信令。 This document obsoletes RFC 3057. 本文件淘汰RFC 3057。 Table of Contents. 目录. 1. Introduction ....................................................3. 1.1. Scope ......................................................3.

2001年2月1日 · In this document, the term Q.921-User refers to an upper layer which uses the services of Q.921, not the user side of ISDN interface [1]. Examples of the upper layer would be Q.931 and QSIG.