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-rw-r--r--lib/asn1/doc/src/asn1_ug.xml104
1 files changed, 38 insertions, 66 deletions
diff --git a/lib/asn1/doc/src/asn1_ug.xml b/lib/asn1/doc/src/asn1_ug.xml
index 18aa0b1d87..e39b47ff20 100644
--- a/lib/asn1/doc/src/asn1_ug.xml
+++ b/lib/asn1/doc/src/asn1_ug.xml
@@ -34,23 +34,25 @@
<section>
<title>Features</title>
- <p>The Asn1 application provides:
- </p>
+ <p>The Asn1 application provides:</p>
<list type="bulleted">
<item>An ASN.1 compiler for Erlang, which generates encode and
decode functions to be used by Erlang programs sending and
receiving ASN.1 specified data.</item>
<item>Run-time functions used by the generated code.</item>
- <item>The supported encoding rules are:
+ <item>Support for the following encoding rules:
<list>
<item>
Basic Encoding Rules (<em>BER</em>)
</item>
<item>
- Distinguished Encoding Rules (<em>DER</em>), a specialized form of BER that is used in security-conscious applications.
+ Distinguished Encoding Rules (<em>DER</em>), a specialized
+ form of BER that is used in security-conscious
+ applications.
</item>
<item>
- Packed Encoding Rules (<em>PER</em>) both the aligned and unaligned variant.
+ Packed Encoding Rules (<em>PER</em>); both the aligned and
+ unaligned variant.
</item>
</list>
</item>
@@ -59,71 +61,41 @@
<section>
<title>Overview</title>
- <p>ASN.1 (Abstract Syntax Notation 1) is a formal language for describing data structures to be exchanged between distributed computer systems.
- The purpose of ASN.1 is to have
- a platform and programming language independent notation to express
- types using a
- standardized set of rules for the transformation of values of
- a defined type, into a stream of bytes. This stream of bytes
- can then be sent on a communication channel set up by the
- lower layers in the stack of communication protocols e.g.
- TCP/IP or encapsulated within UDP packets. This way, two
- different applications written in two completely different
- programming languages running on different computers with
- different internal representation of data can exchange
- instances of structured data types (instead of exchanging
- bytes or bits). This makes programming faster and easier since no code
- has to be written to process the transport format of the
- data.
- </p>
- <p>To write a network application which processes ASN.1 encoded
- messages, it is prudent and sometimes essential to have a set
- of off-line development tools such as an ASN.1 compiler which
- can generate the encode and decode logic for the specific ASN.1
- data types. It is also necessary to combine this with some
- general language-specific runtime support for ASN.1 encoding and
- decoding.
- </p>
- <p>The ASN.1 compiler must be directed towards a target language
- or a set of closely related languages. This manual describes a
- compiler which is directed towards the functional language
- Erlang. In order to use this compiler, familiarity with the
- language Erlang is essential. Therefore, the runtime support for ASN.1 is
- also closely related to the language Erlang and
- consist of a number of functions, which the
- compiler uses. The types in ASN.1 and how to represent
- values of those types in Erlang are described in this manual.
- </p>
- <p>The following document is structured so that the first part describes
- how to use ASN.1 compiler, and then there are descriptions of all
- the primitive and constructed ASN.1 types and their representation
- in Erlang,
- </p>
+ <p>ASN.1 (Abstract Syntax Notation One) is a formal language for
+ describing data structures to be exchanged between distributed
+ computer systems. The purpose of ASN.1 is to have a platform
+ and programming language independent notation to express types
+ using a standardized set of rules for the transformation of
+ values of a defined type into a stream of bytes. This stream of
+ bytes can then be sent on any type of communication
+ channel. This way, two applications written in different
+ programming languages running on different computers with
+ different internal representation of data can exchange instances
+ of structured data types.</p>
</section>
<section>
<title>Prerequisites</title>
- <p>It is assumed that the reader is familiar with the ASN.1 notation
- as documented in the standard definition [<cite id="X.680"></cite>] which is
- the primary text. It may also be helpful, but not necessary,
- to read the standard definitions
- [<cite id="X.681"></cite>] [<cite id="X.682"></cite>] [<cite id="X.683"></cite>]
- [<cite id="X.690"></cite>] [<cite id="X.691"></cite>]. </p>
- <p>A very good book explaining those reference texts is
- [<cite id="DUBUISSON"></cite>], free to download at
- <url href="http://www.oss.com/asn1/dubuisson.html">http://www.oss.com/asn1/dubuisson.html </url>.
+ <p>It is assumed that the reader is familiar with the ASN.1
+ notation as documented in the standard definition [<cite
+ id="X.680"></cite>] which is the primary text. It may also be
+ helpful, but not necessary, to read the standard definitions
+ [<cite id="X.681"></cite>] [<cite id="X.682"></cite>] [<cite
+ id="X.683"></cite>] [<cite id="X.690"></cite>] [<cite
+ id="X.691"></cite>]. </p>
+ <p>A good book explaining those reference texts is
+ [<cite id="DUBUISSON"></cite>], which is free to download at
+ <url href="http://www.oss.com/asn1/dubuisson.html">http://www.oss.com/asn1/dubuisson.html</url>.
</p>
</section>
<section>
- <title>Capability</title>
+ <title>Capabilities</title>
<p>This application covers all features of ASN.1 up to the 1997
- edition of the specification. In the 2002 edition of ASN.1 a number of
- new features where introduced of which some are supported while
- others are not. For example the
- ECN (Encoding Control Notation) and XML notation are still
- unsupported. Though, the other features of the 2002 edition are
- fully or partly supported as shown below:</p>
+ edition of the specification. In the 2002 edition of ASN.1 a
+ number of new features were introduced. The following features
+ of the 2002 edition are fully or partly supported as shown
+ below:</p>
<list type="bulleted">
<item>
<p>Decimal notation (e.g., "1.5e3") for REAL values. The
@@ -131,7 +103,7 @@
supported.</p>
</item>
<item>
- <p>The RELATIVE-OID type for relative object identifiers are
+ <p>The RELATIVE-OID type for relative object identifiers is
fully supported.</p>
</item>
<item>
@@ -141,16 +113,16 @@
constraint is not a PER-visible constraint.</p>
</item>
<item>
- <p>The subtype constraint by regular expressions (PATTERN) for character string types is parsed when compiling, but no further action is taken. This constraint is not a PER-visible constraint.</p>
+ <p>The subtype constraint by regular expressions (PATTERN)
+ for character string types is parsed when compiling, but no
+ further action is taken. This constraint is not a
+ PER-visible constraint.</p>
</item>
<item>
<p>Multiple-line comments as in C, <c>/* ... */</c>, are
supported.</p>
</item>
</list>
- <p>It should also be added here that the encoding formats
- supported are <em>BER</em>, <em>DER</em>, <em>PER aligned
- basic</em> variant and <em>PER unaligned basic</em> variant.</p>
</section>
</section>