COVESA · UlfBj · Mar 17, 2026 · Mar 17, 2026
diff --git a/README.md b/README.md
@@ -8,10 +8,6 @@
 
 Ulf Björkengren - Ford Motor Company
 
-Ted Guild - Geotab Inc.
-
-Peter Winzell - Volvo Cars
-
 Wonsuk Lee - 한국전자통신연구원(ETRI)
 
 ### Lead editors
@@ -25,20 +21,31 @@ Minutes of meetings is found [here](https://covesa.atlassian.net/wiki/spaces/WIK
 
 ## Overview
 
->Vehicle Information Service Specification (VISS) is an API for accessing the COVESA Vehicle Signal Specification (VSS) data. The work started at [The World Wide Web Consortium (W3C)](https://www.w3.org) in collaboration with GENIVI and its successor COVESA. The W3C Automotive Working Group closed in February of 2024 and the work is continuing at COVESA.
+Vehicle Information Service Specification (VISS) is an API for accessing the COVESA Vehicle Signal Specification (VSS) data. The work started at [The World Wide Web Consortium (W3C)](https://www.w3.org) in collaboration with GENIVI and its successor COVESA. The W3C Automotive Working Group closed in February of 2024 and the work is continuing at COVESA.
+
+The VISS specification consists of the following documents:
+* Core
+* Transport
+* Payload Encoding
+
+The specification is supplemented with the following documents:
+* Implementation Guidelines
 
 To see the most recent HTML rendered version of the specifications from this repository can be found at the following:
 
 - [COVESA VISS version 3.1 - Core](https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Core.html)
-- [COVESA VISS version 3.1-Payload Encoding](https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_PayloadEncoding.html)
 - [COVESA VISS version 3.1-Transport](https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Transport.html)
+- [COVESA VISS version 3.1-Payload Encoding](https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_PayloadEncoding.html)
+- [COVESA VISS-Implementation Guidelines version 1.0](https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISS_ImplementationGuidelines.v1.0.html)
 
 The [VISS explainer](./VISS-explainer.md) gives some background and rationale to this interface.
 
 ## Latest version
-[VISS version 3.0](https://github.com/COVESA/vehicle-information-service-specification/releases/tag/v3.0)
+[VISS version 3.1](https://github.com/COVESA/vehicle-information-service-specification/releases/tag/v3.1rc1)
 
 ## Previous versions
+[VISS version 3.0](https://github.com/COVESA/vehicle-information-service-specification/releases/tag/v3.0)
+
 [VISS version 2.0](https://github.com/COVESA/vehicle-information-service-specification/releases/tag/v2.0)
 
 [VISS version 1](https://www.w3.org/TR/vehicle-information-service/)

diff --git a/spec/VISS_ImplementationGuidelines.v1.0.html b/spec/VISS_ImplementationGuidelines.v1.0.html
@@ -0,0 +1,187 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset='utf-8'>
+    <title>COVESA VISS - Implementation Guidelines version 1.0</title>
+    <script src='https://www.w3.org/Tools/respec/respec-w3c' class='remove' defer></script>
+    <script class='remove'>
+      var respecConfig = {
+        latestVersion: null,
+        github: "https://github.com/COVESA/vehicle-information-service-specification",
+        specStatus: "base",
+	logos: [{
+	  src: "https://raw.githack.com/COVESA/vehicle-information-service-specification/main/spec/images/covesa.jpg",
+          url: "https://covesa.global",
+          alt: "COVESA",
+          height: 50,
+          id: "covesa-logo",
+        }],
+        editors: [{
+          name: "Ulf Bjorkengren",
+          company: "Ford Motor Company",
+          url: "mailto:ubjorken@ford.com",
+          companyURL: "https://www.ford.com",
+        },
+        {
+          name: "Sergej Saibel",
+          company: "Traton",
+          url: "mailto:sergej.saibel@scania.com",
+          companyURL: "https://traton.com/en.html"
+        }],
+        edDraftURI: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISS_ImplementationGuidelines.v1.0.html",
+        shortName: "viss-implementation-guidelines-v1.0",
+        localBiblio: {
+          "CORE": {
+            title: "COVESA VISS version 3.1 - Core",
+            href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Core.html",
+            publisher: "Ulf Bjorkengren; Wonsuk Lee"
+          },
+          "TRANSPORT": {
+            title: "COVESA VISS version 3.1-Transport",
+            href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Transport.html",
+            publisher: "Ulf Bjorkengren; Wonsuk Lee"
+          },
+          "PAYLOAD ENCODING": {
+             title: "COVESA VISS version 3.1-Payload Encoding",
+             href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_PayloadEncoding.html",
+             publisher: "Ulf Bjorkengren; Wonsuk Lee",
+          },
+        },
+      };
+    </script>
+    <style>
+      table.parameters, table.exceptions {
+          border-spacing: 0;
+          border-collapse:    collapse;
+          margin: 0.5em 0;
+          width:  100%;
+      }
+      table.parameters { border-bottom:  1px solid #90b8de; }
+      table.exceptions { border-bottom:  1px solid #deb890; }
+
+      .parameters th, .exceptions th {
+          color:  inherit;
+          padding:    3px 5px;
+          text-align: left;
+          font-weight:    normal;
+      }
+      .parameters th { color: #fff; background: #005a9c; }
+      .exceptions th { background: #deb890; }
+
+      .parameters td, .exceptions td {
+          padding:    3px 10px;
+          border-top: 1px solid #ddd;
+          vertical-align: top;
+      }
+
+      .parameters tr:first-child td, .exceptions tr:first-child td {
+          border-top: none;
+      }
+
+      .parameters td.prmName, .exceptions td.excName, .exceptions td.excCodeName {
+          width:  100px;
+      }
+
+      .parameters td.prmType {
+          width:  120px;
+      }
+
+      table.exceptions table {
+          border-spacing: 0;
+          border-collapse:    collapse;
+          width:  100%;
+      }
+
+      .simple {
+        width:100%;
+      }
+
+      thead th{
+        border-bottom: 1px solid black;
+      }
+
+      .simple tbody th{
+        width:33%;
+        background: white;
+        color: black;        
+      }
+      pre { white-space: pre-wrap;}
+  </style>    
+  </head>
+  <body>
+    <p class="copyright">Copyright © 2025 COVESA®.</p>
+    <section id='abstract'>
+      <p>
+        The Vehicle Information Service Specification (VISS) is a
+        service for accessing vehicle information, including signals from sensors
+        on control units within a vehicle's network. This information is exposed through a hierarchical, 
+        tree-like taxonomy as defined in the COVESA <a href="https://github.com/COVESA/hierarchical_information_model">Hierarchical Information Model</a> (HIM), 
+        and is provided in JSON format. The VISS service may be hosted within the vehicle or on external servers, 
+        using data that has already been off-boarded.
+      </p>
+      <p>
+        VISS enables a broad range of use cases, including predictive maintenance, usage-based insurance, fleet management, 
+        and real-time driver assistance services.
+        In the context of artificial intelligence, VISS serves as a critical data access layer, providing high-quality, 
+        real-time vehicle data that can be utilized by AI algorithms for tasks such as anomaly detection, 
+        driver behavior analysis, energy optimization, and contextual decision-making.
+      </p>
+      <p>
+        The first version of VISS, which has been implemented and deployed in production vehicles,
+        supported only WebSocket as a transport protocol.<br>
+        The <a href="https://github.com/COVESA/vehicle-information-service-specification/releases/tag/v2.0">second version</a>
+        is generalized to work across also the HTTP and MQTT transport protocols to improve the support for different use cases.
+        It also contains improved subscription capabilities and added an access control mechanism.<br>
+        The <a href="https://github.com/COVESA/vehicle-information-service-specification/releases/tag/v3.0">third version</a>
+        included the gRPC transport protocol but also simplified addition of other transport protocols by placing the normative requirement
+        on the message payload only, and not also on what transport protocol to use.
+        Several new features were added such as file transfer, payload encoding, and improved server capabilities representation.<br>
+        This specification, the version 3.1, is a backwards compatible extension of the third version of VISS.
+        Instead of referencing to the VSS rule set for how to define the content of a tree it refers to the HIM data profile rule set.
+        This enables also other trees than the VSS tree to be used, a server may manage a set of trees, a forest, that a client can access.
+        Other changes are minor adaptations to support the concept of having a forest of trees, such as adding support for a client to do a forest inquiry.
+      </p>     
+      <p>
+        There are three parts to this specification, [[CORE]], [[TRANSPORT]], and PAYLOAD ENCODING. This document, the VISS version 3.1 PAYLOAD ENCODING specification, 
+        describes the VISSv3.1 payload encodings that is used in some cases. 
+        The companion specifications [[CORE]] describes the messaging layer,
+        and [[TRANSPORT]] describes the deviations form the CORE specification that are used by some transport protocols.
+      </p>
+    </section>
+
+    <section id="introduction">
+      <h2>Introduction</h2>
+      <p>
+      This document supplements the VISS specification by providing recommendations on how to implement certain aspects of the specification.
+      Thesa aspects are typically not explicitly exposed in the VISS interface but different implementations may lead to different behaviors
+      leading to clients receiving different responses from different implementations.
+      This may make interoperability more complicated to achieve,
+      i. e. that a client shall be able to exercise the interface with any implementation of it.
+      </p>
+    </section>
+
+    <section id="conformance"></section>
+
+    <section id="terminology">
+      <h2>Terminology</h2>
+      <p>
+      The acronym 'VISSv3.1' is used to refer to this document, the VISS version 3.1 specification.
+      The acronym 'HIM' is used to refer to the <a href="https://github.com/COVESA/hierarchical_information_model">'Hierarchical Information Model'</a>
+      which is hosted by COVESA.
+      The acronym 'VSS' is used to refer to the <a href="https://github.com/COVESA/vehicle_signal_specification">'Vehicle Signal Specification'</a>
+      which is hosted by COVESA.
+      The term 'WebSocket' when used in this specification, is as defined in the
+      <a href="https://www.w3.org/TR/websockets/">W3C WebSocket API</a> and [[RFC6455]], the WebSocket Protocol.
+      </p>
+    </section>
+
+      <section id="can-bus-specific-error-reorting">
+        <h2>CAN Bus Specific Error Reporting</h2>
+        <p>
+        xxx.
+        </p>
+      </section>
+
+
+  </body>
+</html>
diff --git a/spec/VISSv3.1_Core.html b/spec/VISSv3.1_Core.html
@@ -41,15 +41,20 @@
             "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Core.html",
          shortName: "viss3.1-core",
          localBiblio: {
+            "TRANSPORT": {
+               title: "COVESA VISS version 3.1-Transport",
+               href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Transport.html",
+               publisher: "Ulf Bjorkengren; Wonsuk Lee",
+            },
             "PAYLOAD ENCODING": {
                title: "COVESA VISS version 3.1-Payload Encoding",
                href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_PayloadEncoding.html",
                publisher: "Ulf Bjorkengren; Wonsuk Lee",
             },
-            TRANSPORT: {
-               title: "COVESA VISS version 3.1-Transport",
-               href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISSv3.1_Transport.html",
-               publisher: "Ulf Bjorkengren; Wonsuk Lee",
+            "IMPLEMENTATION_GUIDELINES": {
+               title: "COVESA VISS Implementation Guidelines version 1.0",
+               href: "https://raw.githack.com/COVESA/vehicle-information-service-specification/v3.1/spec/VISS_ImplementationGuidelines.v1.0.html",
+               publisher: "Ulf Bjorkengren; Sergej Saibel",
             },
          },
       };