Juergen Schoenwaelder
Internet-Draft TU Braunschweig
Expires May 1999 18 November 1998
Textual Conventions Extension 1
<draft-schoenw-snmp-tc-ext-00.txt>
Status of this Memo
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Abstract
This memo defines new textual conventions that are considered to be
generally useful. This memo extends the set of textual conventions
defined in RFC 1903, which also defines the language used to define
textual conventions.
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Table of Contents
1 Introduction ................................................. 2
2 Definitions .................................................. 2
3 Acknowledgments .............................................. 5
4 Authors' Address ............................................. 5
1. Introduction
This memo defines new textual conventions that are considered to be
generally useful. It extends the set of textual conventions defined
in RFC 1903. For more information about textual conventions, please
consult RFC 1903.
2. Definitions
SNMPv2-TC-EXT-01 DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY
FROM SNMPv2-SMI
TEXTUAL-CONVENTION
FROM SNMPv2-TC;
-- This module is not valid SMIv2. The author left out all the
-- administrative stuff in order to keep it small.
InternationalString ::= TEXTUAL-CONVENTION
DISPLAY-HINT "255t"
STATUS current
DESCRIPTION
"An octet string containing human-readable information.
To facilitate internationalization, this information is
represented using the ISO/IEC IS 10646-1 character set,
encoded as an octet string using the UTF-8 transformation
format described in [RFC2279].
Since additional code points are added by amendments to the
10646 standard from time to time, implementations must be
prepared to encounter any code point from 0x00000000 to
0x7fffffff. Byte sequences that do not correspond to the
valid UTF-8 encoding of a code point or are outside this
range are prohibited.
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The use of control codes should be avoided. When it is
necessary to represent a newline, the control code sequence
CR LF should be used.
For code points not directly supported by user interface
hardware or software, an alternative means of entry and
display, such as hexadecimal, may be provided.
For information encoded in 7-bit US-ASCII, the UTF-8 encoding
is identical to the US-ASCII encoding.
UTF-8 may require multiple bytes to represent a single
character / code point; thus the length of this object in
octets may be different from the number of characters
encoded. Similarly, size constraints refer to the number of
encoded octets, not the number of characters represented by
an encoding.
Note that when this TC is used for an object that is used or
envisioned to be used as an index, then a SIZE restriction
MUST be specified so that the number of sub-identifiers for
any object instance does not exceed the limit of 128, as
defined by [RFC1905].
Note that the size of an InternationalString object is
measured in octets, not characters."
SYNTAX OCTET STRING (SIZE (0..255))
TAddressOrZero ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"Denotes a transport service address. A zero-length octet
string indicates that no transport address is known.
A TAddress value is always interpreted within the context of
a TDomain value. Thus, each definition of a TDomain value
must be accompanied by a definition of a textual convention
for use with that TDomain. Some possible textual conventions,
such as SnmpUDPAddress for snmpUDPDomain, are defined in the
SNMPv2-TM MIB module. Other possible textual conventions are
defined in other MIB modules.
Note, the definition of this textual convention is identical
to the TAddress definition in the SNMPv2-TM MIB module with
the only difference that this textual convention allows a
zero-length TAddress value."
SYNTAX OCTET STRING (SIZE (0..255))
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TAddressMask ::=
STATUS current
DESCRIPTION
"Denotes a transport service address mask.
A mask value is used to select which bits of a transport
address must match bits of the corresponding instance of
a TAddress object. The value of an instance of this textual
convention must always be an OCTET STRING whose length is
either zero or the same as that of the corresponding instance
of a TAddress object.
The matching algorithm is as follows:
Each bit of each octet in the TAddressMask value corresponds
to the same bit of the same octet in the TAddress value. For
bits that are set in the TAddressMask value (i.e. bits equal
to 1), the corresponding bits in the TAddress value must
match the bits in a given transport address. If all such bits
match, the transport address is matched. Otherwise, the match
fails."
SYNTAX OCTET STRING (SIZE (1..255))
TAddressMaskOrZero ::=
STATUS
DESCRIPTION
"Denotes a transport service address mask. A zero-length octet
string indicates that the match always succeeds.
A mask value is used to select which bits of a transport
address must match bits of the corresponding instance of
a TAddress object. The value of an instance of this textual
convention must always be an OCTET STRING whose length is
either zero or the same as that of the corresponding instance
of a TAddress object.
The matching algorithm is as follows:
If the value of the TAddressMask is a zero-length OCTET
STRING, the mask value is ignored and the match succeeds.
Otherwise, each bit of each octet in the TAddressMask value
corresponds to the same bit of the same octet in the
TAddress value. For bits that are set in the TAddressMask
value (i.e. bits equal to 1), the corresponding bits in the
TAddress value must match the bits in a given transport
address. If all such bits match, the transport address is
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matched. Otherwise, the match fails."
SYNTAX OCTET STRING (SIZE (0..255))
END
3. Acknowledgments
The definitions in this memo are inspired by definitions found in
other RFCs and Internet-Drafts. Most of the text in the descriptions
is therefore copied from other sources. Special thanks go to David
Levi, Randy Presuhn and Keith McCloghrie for writing the original
descriptions.
4. Authors' Address
Juergen Schoenwaelder Email: schoenw@ibr.cs.tu-bs.de
TU Braunschweig Tel: +49 531 391-3283
Bueltenweg 74/75
38106 Braunschweig
Germany
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