私有综合服务网络（PISN）是一种专用的通信网络，用于在组织内部提供各种通信服务。PISN可以提供多种服务，如语音通信、数据传输、传真、电子邮件等。为了满足用户的不同需求，PISN还提供了一些补充服务，如不打扰和不打扰覆盖。

不打扰服务是指当用户不希望被打扰时，可以通过设置不打扰状态来避免接收来电。在不打扰状态下，来电会被转移到用户的语音信箱或其他指定的号码。不打扰服务可以帮助用户避免在会议、休息或其他重要活动期间被打扰。

不打扰覆盖服务是指当用户处于不打扰状态时，可以通过设置不打扰覆盖状态来接收紧急来电。在不打扰覆盖状态下，紧急来电可以直接呼叫用户的终端设备，而不会被转移到语音信箱或其他号码。不打扰覆盖服务可以帮助用户在紧急情况下及时接收重要来电。

ISO/IEC 14842:1996标准规定了不打扰和不打扰覆盖服务的功能和信息流。该标准定义了不打扰和不打扰覆盖服务的操作和参数，以及与这些服务相关的信息流。该标准还规定了不打扰和不打扰覆盖服务的实现要求，包括用户终端设备和PISN中的服务提供者和网络运营商。

该标准的实施可以帮助PISN用户更好地管理自己的通信需求，提高通信效率和工作效率。同时，该标准还可以促进PISN服务提供者和网络运营商之间的互操作性和互联互通。

相关标准
ISO/IEC 11579-1:1993 Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Circuit-mode basic call control - Part 1: Protocol specification
ISO/IEC 11579-2:1993 Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Circuit-mode basic call control - Part 2: Protocol implementation conformance statement (PICS) proforma
ISO/IEC 11579-3:1993 Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Circuit-mode basic call control - Part 3: Protocol implementation extra information for testing (PIE)
ISO/IEC 11579-4:1993 Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Circuit-mode basic call control - Part 4: Protocol implementation conformance statement (PICS) proforma - supplementary services
ISO/IEC 11579-5:1993 Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Circuit-mode basic call control - Part 5: Protocol implementation extra information for testing (PIE) - supplementary services