1.1 本指南的主要内容提供了通过以下方式实现适用于船舶和海洋计算机系统的通信网络的路线图: 1.1.1 检查数字通信协议作为网络技术基础设施的关系， 1.1.2 概述与网络环境中传输介质的实现相关的网络拓扑和传输技术的基本构建块；和 1.1.3 识别操作系统和环境。 1.2 使用开放系统互连（OSI）模型，该模型提供了网络功能和评估的分层方法，根据与其功能程度和类型相对应的下层和上层协议，在本指南中识别和描述了常见的网络通信协议。 1.3 虽然网络用户、设计者和管理员需要识别和理解每种可能的网络协议，但不可能了解每种协议规范的详细信息。因此，本指南并非旨在全面论述为商业用途开发的每种硬件和软件协议，这一时间跨度约为25年。相反，本指南将向用户简要介绍过去和现在的大多数协议，这些协议可能包括船舶或海上互联网，包括局域网（LAN）、广域网（WAN）以及提供此类网络互操作性和数据传输的相关硬件和软件。 1.4 虽然本指南提供了对各种通信协议的理解，但建议用户查阅参考资料，以获得对各个通信协议的更全面理解。然而，通过检查协议的基本功能并审查本指南中确定的协议表征标准，用户将更容易理解本文未提及或未解决的其他协议。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 本指南旨在提供对广泛通信协议标准的理解，使用户能够更好地了解其对船上网络和海洋平台计算机化系统的适用性。对于计算机化网络和系统，通信协议对于集成各种系统设备、在不同子网之间提供功能或实现远程连接（无论是在码头侧还是通过地球物理通信技术）都是必要的。 4.2 数字通信协议标准的种类和范围广泛，大大增加了为无数潜在船上系统的系统应用和相关设备指定兼容协议的复杂决策过程。 然而，用户必须确定初始网络需求，因此，一旦被评估的网络协议被充分理解，决策过程就应该确定适当的网络协议。因此，本指南旨在降低协议选择和实现的复杂性。 4.3 网络协议定义了一个约定的、可量化的实体或一组规则，用户计算机、系统网络和互联网设备通过该实体进行通信和交换信息。通信协议规定了基本的网络准则，如物理接口连接，或两台通信计算机之间的数据格式和控制操作。 船舶和海上数字通信协议要求与陆基网络通信协议要求相同。两者都需要在各种协议类别中进行标准化的协议选择，包括LAN标准、WAN协议、LAN/WAN协议、网络管理、接线中心配置/操作、硬件平台、操作系统和网络应用程序。

1.1 The principal content of this guide provides a road map to implement a communication network applicable to ship and marine computer systems by: 1.1.1 Examining the relationship of digital communication protocols as a network technological infrastructure, 1.1.2 Outlining the basic building blocks of network topologies and transmission techniques associated with the implementation of transmission media in a network environment; and, 1.1.3 Identifying operating system and environments. 1.2 Using the Open System Interconnection (OSI) model, which provides a layered approach to network functionality and evaluation, common network communications protocols are identified and characterized in this guide according to lower and upper layer protocols corresponding to their degree and type of functionality. 1.3 Although it is desirable that network users, designers, and administrators recognize and understand every possible networking protocol, it is not possible to know the intimate details of every protocol specification. Accordingly, this guide is not intended to address fully every hardware and software protocol ever developed for commercial use, which spans a period of about 25 years. Instead, the user of this guide will be introduced to a brief overview of the majority of past and present protocols which may comprise a ship or marine internetwork, to include Local Area Networks (LANs), Wide Area Networks (WANs), and related hardware and software that provide such network interoperability and data transfer. 1.4 While this guide provides an understanding of the wide range of communication protocols, the user is recommended to consult the reference material for acquiring a more comprehensive understanding of individual communication protocols. However, by examining the basic functions of protocols and reviewing the protocol characterization criteria identified in this guide, the user will be more apt to understanding other protocols not mentioned or addressed herein. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 This guide is intended to provide an understanding of the wide range of communication protocols standards, allowing the user to understand better their applicability to shipboard networks and marine platform computerized systems. For computerized networks and systems, communication protocols are necessary for integrating various system devices, providing functionality between dissimilar subnetworks, or for enabling remote connections, either pier side or through geophysical communication technologies. 4.2 The wide variety and scope of digital communication protocol standards adds greatly to the complex decision process for specifying compatible protocols for system applications and related devices for the myriad of potential shipboard systems. However, the user must identify the initial networking requirements, so once the network protocols under evaluation are well understood, the decision process should determine the appropriate network protocols. Therefore, this guide is intended to reduce the complexity involved with protocol selection and implementation. 4.3 Network protocols define an agreed, quantifiable entity, or set of rules, by which user computers, system networks, and internetworking devices communicate and exchange information. Communication protocols specify essential networking guidelines, such as physical interface connections, or data format and control operations between two communicating computers. Ship and marine digital communication protocol requirements are no different than their land-based networked counterparts. Both require standardized protocol selection, in various protocol categories, including LAN standards, WAN protocols, LAN/WAN protocols, network management, wiring hub configurations/operations, hardware platforms, operating systems, and network applications.