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CCITT的X.25链路级规程是ISO的HDLC的一个子集,它的目的是以物理级规程为基础,在两个物理站点之间建立数据链路,为分组级规程提供无差错的数据传输,为DTE和DCE提供可靠而有效的接口。 X.25链路级规程的实现可以是多种多样的。在统一的规程原理的指导下,各种实现在内部的技术细节上可能会有不少差别;但是,只要外部特性一样,并不妨碍这些实现之间的接口与通讯。为了实现X.25链路级规程,开辟数据通讯路径,必须采用智
The CCITT X.25 link-level specification is a subset of the HDLC for ISO. Its purpose is to establish a data link between two physical sites based on a physical-level protocol, providing error-free data for packet-level procedures Transmission, provide a reliable and effective interface for DTE and DCE. X.25 link-level procedures can be implemented in a wide variety of ways. Under the guidance of a uniform set of rules, various implementations may have quite a few differences in internal technical details; however, as long as the external characteristics do not interfere with the interface and communication between these implementations. In order to achieve X.25 link-level procedures, opening up data communication path, we must adopt wisdom