ACAP -- Application Configuration Access Protocol
RFC 2244

Network Working Group                                          C. Newman
Request for Comments: 2244                                      Innosoft
Category: Standards Track                                    J. G. Myers
                                                                Netscape
                                                           November 1997

           ACAP -- Application Configuration Access Protocol

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society 1997.  All Rights Reserved.

Abstract

   The Application Configuration Access Protocol (ACAP) is designed to
   support remote storage and access of program option, configuration
   and preference information.  The data store model is designed to
   allow a client relatively simple access to interesting data, to allow
   new information to be easily added without server re-configuration,
   and to promote the use of both standardized data and custom or
   proprietary data.  Key features include "inheritance" which can be
   used to manage default values for configuration settings and access
   control lists which allow interesting personal information to be
   shared and group information to be restricted.

Newman & Myers              Standards Track                     [Page i]


RFC 2244                          ACAP                     November 1997

                           Table of Contents

Status of this Memo ...............................................    i
Copyright Notice ..................................................    i
Abstract ..........................................................    i
ACAP Protocol Specification .......................................    1
1.       Introduction .............................................    1
1.1.     Conventions Used in this Document ........................    1
1.2.     ACAP Data Model ..........................................    1
1.3.     ACAP Design Goals ........................................    1
1.4.     Validation ...............................................    2
1.5.     Definitions ..............................................    2
1.6.     ACAP Command Overview ....................................    4
2.       Protocol Framework .......................................    4
2.1.     Link Level ...............................................    4
2.2.     Commands and Responses ...................................    4
2.2.1.   Client Protocol Sender and Server Protocol Receiver ......    4
2.2.2.   Server Protocol Sender and Client Protocol Receiver ......    5
2.3.     Server States ............................................    6
2.3.1.   Non-Authenticated State ..................................    6
2.3.2.   Authenticated State ......................................    6
2.3.3.   Logout State .............................................    6
2.4.     Operational Considerations ...............................    7
2.4.1.   Untagged Status Updates ..................................    7
2.4.2.   Response when No Command in Progress .....................    7
2.4.3.   Auto-logout Timer ........................................    7
2.4.4.   Multiple Commands in Progress ............................    8
2.5.     Server Command Continuation Request ......................    8
2.6.     Data Formats .............................................    8
2.6.1.   Atom .....................................................    9
2.6.2.   Number ...................................................    9
2.6.3.   String ...................................................    9
2.6.3.1. 8-bit and Binary Strings .................................   10
2.6.4.   Parenthesized List .......................................   10
2.6.5.   NIL ......................................................   10
3.       Protocol Elements ........................................   10
3.1.     Entries and Attributes ...................................   10
3.1.1.   Predefined Attributes ....................................   11
3.1.2.   Attribute Metadata .......................................   12
3.2.     ACAP URL scheme ..........................................   13
3.2.1.   ACAP URL User Name and Authentication Mechanism ..........   13
3.2.2.   Relative ACAP URLs .......................................   14
3.3.     Contexts .................................................   14

Newman & Myers              Standards Track                    [Page ii]


RFC 2244                          ACAP                     November 1997