RFC 1317
Definitions of Managed Objects for RS-232-like Hardware Devices
RFC 1317: Definitions of Managed Objects for RS-232-like Hardware Devices 🎀
okay bestie, so this is RFC 1317, written by B. Stewart as the editor, from Xyplex, Inc., and dated April 1992. It's an IAB standards track protocol. The header doesn't list any RFCs it obsoletes or updates. ✨
Status of this Memo 📜
This document is an IAB standards track protocol for the Internet community, and it's asking for discussion and suggestions for improvements. For the standardization state and status of this protocol, check the current edition of the "IAB Official Protocol Standards." Distribution of this memo is unlimited. 💅
1. Abstract 💖
This memo defines a chunk of the Management Information Base (MIB) for network management protocols in TCP/IP based internets. It's all about objects for managing RS-232-like devices. 🔌
2. The Network Management Framework 🧚
The Internet-standard Network Management Framework is made of three components, and they're a whole team. 👑
RFC 1155 defines the SMI, which is the mechanism for describing and naming objects for management purposes. RFC 1212 gives a more concise description mechanism, and it's wholly consistent with the SMI. 🌸
RFC 1156 defines MIB-I, the core set of managed objects for the Internet suite of protocols. RFC 1213 defines MIB-II, which is an evolution of MIB-I based on implementation experience and new operational requirements. 📈
RFC 1157 defines the SNMP, the protocol used for network access to managed objects. 🦋
The Framework permits new objects to be defined for experimentation and evaluation. 🧪
3. Objects 🍓
Managed objects are accessed through a virtual information store called the Management Information Base, or MIB. Objects in the MIB are defined using the subset of Abstract Syntax Notation One (ASN.1) [7] that's defined in the SMI. Each object has a name, a syntax, and an encoding. The name is an object identifier, which is an administratively assigned name that specifies an object type. 🗂️
The object type together with an object instance is what uniquely identifies a specific instantiation of the object. For human convenience, we often use a textual string, called the OBJECT DESCRIPTOR, to also refer to the object type. 🏷️
The syntax of an object type defines the abstract data structure that corresponds to that object type, and the ASN.1 language is used for this. The SMI [3] purposely restricts which ASN.1 constructs may be used. These restrictions are explicitly made for simplicity. 🫶
The encoding of an object type is simply how that object type is represented using its syntax. Implicitly tied to an object type's syntax and encoding is how the object type is represented when it's being transmitted on the network. 📡
The SMI specifies the use of the basic encoding rules of ASN.1 [8], subject to the additional requirements imposed by the SNMP. 🔐
3.1. Format of Definitions 🎀
Section 5 contains the specification of all object types in this MIB module. The object types are defined using the conventions in the SMI, as amended by the extensions specified in [9,10]. 📖
4. Overview 🌈
The RS-232-like Hardware Device MIB applies to interface ports that might logically support the Interface MIB, a Transmission MIB, or the Character MIB. The most common example is an RS-232 port with modem signals. 🔌✨
The RS-232-like MIB is one of a set of MIBs designed for complementary use. At the time of writing, the set is:
Character MIB
PPP MIB
RS-232-like MIB
Parallel-printer-like MIBThe RS-232-like MIB and the Parallel-printer-like MIB represent the physical layer, and they provide service to higher layers such as the Character MIB or PPP MIB. Further MIBs may appear above these. 🧱
Here's the diagram showing two possible "MIB stacks," each using the RS-232-like MIB. 👀
.-----------------.
.-----------------. | Standard MIB |
| Telnet MIB | | Interface Group |
|-----------------| |-----------------|
| Character MIB | | PPP MIB |
|-----------------| |-----------------|
| RS-232-like MIB | | RS-232-like MIB |
`-----------------' `-----------------'The idea behind the model is that the physical-level MIBs represent the lowest level, no matter which higher level is using them. Separate higher level MIBs then represent specific applications, like a terminal (the Character MIB) or a network connection (the PPP MIB). 💫
The RS-232-like Hardware Device MIB is mandatory for all systems that have a hardware port supporting services managed through some other MIB, for example the Character MIB or PPP MIB. 💅
The MIB includes multiple similar types of hardware, so it contains objects that aren't applicable to all of those types. Those objects live in a separate branch of the MIB, which is required when applicable and otherwise absent. 🌿
The RS-232-like Hardware Port MIB includes RS-232, RS-422, RS-423, V.35, and other asynchronous or synchronous serial physical links with a similar set of control signals. ⚡
The MIB contains objects related to physical layer connections. Those connections may provide interesting hardware signals (other than for basic data transfer), such as RNG and DCD. Hardware ports also have attributes like speed and bits per character. 🔥
The usefulness of error counters in this MIB depends on the presence of non-error character counts in higher level MIBs. 🧮
The MIB comprises one base object and four tables, which are detailed in the following sections. The tables contain objects for all ports, asynchronous ports, and input and output control signals. 🍰
5. Definitions 🧚♀️
Here's the MIB module itself. This part covers the generic RS-232-like group, so grab a snack. 🍿
RFC1317-MIB DEFINITIONS ::= BEGIN
IMPORTS
Counter
FROM RFC1155-SMI
transmission
FROM RFC1213-MIB
OBJECT-TYPE
FROM RFC-1212;
-- this is the MIB module for RS-232-like hardware devices
rs232 OBJECT IDENTIFIER ::= { transmission 33 }
-- the generic RS-232-like group
-- Implementation of this group is mandatory for all
-- systems that have RS-232-like hardware ports
-- supporting higher level services such as character
-- streams or network interfaces
rs232Number OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of ports (regardless of their current
state) in the RS-232-like general port table."
::= { rs232 1 }
-- the RS-232-like general Port table
rs232PortTable OBJECT-TYPE
SYNTAX SEQUENCE OF Rs232PortEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A list of port entries. The number of entries is
given by the value of rs232Number."
::= { rs232 2 }
rs232PortEntry OBJECT-TYPE
SYNTAX Rs232PortEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"Status and parameter values for a port."
INDEX { rs232PortIndex }
::= { rs232PortTable 1 }
Rs232PortEntry ::=
SEQUENCE {
rs232PortIndex
INTEGER,
rs232PortType
INTEGER,
rs232PortInSigNumber
INTEGER,
rs232PortOutSigNumber
INTEGER,
rs232PortInSpeed
INTEGER,
rs232PortOutSpeed
INTEGER }
rs232PortIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"A unique value for each port. Its value ranges
between 1 and the value of rs232Number. By
convention and if possible, hardware port numbers
map directly to external connectors. The value for
each port must remain constant at least from one
re-initialization of the network management agent to
the next."
::= { rs232PortEntry 1 }
rs232PortType OBJECT-TYPE
SYNTAX INTEGER { other(1), rs232(2), rs422(3),
rs423(4), v35(5) }
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The port's hardware type."
::= { rs232PortEntry 2 }
rs232PortInSigNumber OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of input signals for the port in the
input signal table (rs232PortInSigTable). The table
contains entries only for those signals the software
can detect."
::= { rs232PortEntry 3 }
rs232PortOutSigNumber OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of output signals for the port in the
output signal table (rs232PortOutSigTable). The
table contains entries only for those signals the
software can assert."
::= { rs232PortEntry 4 }
rs232PortInSpeed OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The port's input speed in bits per second."
::= { rs232PortEntry 5 }
rs232PortOutSpeed OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The port's output speed in bits per second."
::= { rs232PortEntry 6 }Part 2 picks up with the Asynchronous Port group. 🦋
Okay bestie, picking up right where we left off 💖 The async port objects come first, and they're giving main character energy 🦋
rs232AsyncPortIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"A unique value for each port. Its value is the
same as rs232PortIndex for the port."
::= { rs232AsyncPortEntry 1 }
rs232AsyncPortBits OBJECT-TYPE
SYNTAX INTEGER (5..8)
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The port's number of bits in a character."
::= { rs232AsyncPortEntry 2 }
rs232AsyncPortStopBits OBJECT-TYPE
SYNTAX INTEGER { one(1), two(2),
one-and-half(3), dynamic(4) }
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The port's number of stop bits."
::= { rs232AsyncPortEntry 3 }
rs232AsyncPortParity OBJECT-TYPE
SYNTAX INTEGER { none(1), odd(2), even(3),
mark(4), space(5) }
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The port's sense of a character parity bit."
::= { rs232AsyncPortEntry 4 }
rs232AsyncPortAutobaud OBJECT-TYPE
SYNTAX INTEGER { enabled(1), disabled(2) }
ACCESS read-write
STATUS mandatory
DESCRIPTION
"A control for the port's ability to automatically
sense input speed.
When rs232PortAutoBaud is 'enabled', a port may
autobaud to values different from the set values for
speed, parity, and character size. As a result a
network management system may temporarily observe
values different from what was previously set."
::= { rs232AsyncPortEntry 5 }
rs232AsyncPortParityErrs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of characters with a parity error,
input from the port since system re-initialization
and while the port state was 'up' or 'test'."
::= { rs232AsyncPortEntry 6 }
rs232AsyncPortFramingErrs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of characters with a framing error,
input from the port since system re-initialization
and while the port state was 'up' or 'test'."
::= { rs232AsyncPortEntry 7 }
rs232AsyncPortOverrunErrs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of characters with an overrun error,
input from the port since system re-initialization
and while the port state was 'up' or 'test'."
::= { rs232AsyncPortEntry 8 }Next up is the synchronous port group 🎀 Here's the deal with this one: it's only needed if the system actually has synchronous ports, and if it doesn't, it just isn't there at all 🙈
-- the RS-232-like Synchronous Port group
-- Implementation of this group is mandatory if the system
-- has any synchronous ports. Otherwise it is not
-- present.
rs232SyncPortTable OBJECT-TYPE
SYNTAX SEQUENCE OF Rs232SyncPortEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A list of synchronous port entries. The maximum
entry number is given by the value of rs232Number.
Entries need not exist for asynchronous ports."
::= { rs232 4 }
rs232SyncPortEntry OBJECT-TYPE
SYNTAX Rs232SyncPortEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"Status and parameter values for a synchronous
port."
INDEX { rs232SyncPortIndex }
::= { rs232SyncPortTable 1 }
Rs232SyncPortEntry ::=
SEQUENCE {
rs232SyncPortIndex
INTEGER,
rs232SyncPortClockSource
INTEGER,
rs232SyncPortFrameCheckErrs
Counter,
rs232SyncPortTransmitUnderrunErrs
Counter,
rs232SyncPortReceiveOverrunErrs
Counter,
rs232SyncPortInterruptedFrames
Counter,
rs232SyncPortAbortedFrames
Counter
}
rs232SyncPortIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"A unique value for each port. Its value is the
same as rs232PortIndex for the port."
::= { rs232SyncPortEntry 1 }
rs232SyncPortClockSource OBJECT-TYPE
SYNTAX INTEGER { internal(1), external(2), split(3) }
ACCESS read-write
STATUS mandatory
DESCRIPTION
"Source of the port's bit rate clock. 'split' means
the tranmit clock is internal and the receive clock
is external."
::= { rs232SyncPortEntry 2 }
rs232SyncPortFrameCheckErrs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of frames with an invalid frame check
sequence, input from the port since system
re-initialization and while the port state was 'up'
or 'test'."
::= { rs232SyncPortEntry 3 }
rs232SyncPortTransmitUnderrunErrs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of frames that failed to be
transmitted on the port since system
re-initialization and while the port state was 'up'
or 'test' because data was not available to the
transmitter in time."
::= { rs232SyncPortEntry 4 }
rs232SyncPortReceiveOverrunErrs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of frames that failed to be received
on the port since system re-initialization and while
the port state was 'up' or 'test' because the
receiver did not accept the data in time."
::= { rs232SyncPortEntry 5 }
rs232SyncPortInterruptedFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Total number of frames that failed to be received
or transmitted on the port due to loss of modem
signals since system re-initialization and while the
port state was 'up' or 'test'."
::= { rs232SyncPortEntry 6 }
rs232SyncPortAbortedFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Number of frames aborted on the port due to
receiving an abort sequence since system
re-initialization and while the port state was 'up'
or 'test'."
::= { rs232SyncPortEntry 7 }Now we've got the input signal table 🦋 This is where the hardware control lines get tracked, so it's lowkey the most iconic part of the whole group 🔥
-- the Input Signal table
rs232InSigTable OBJECT-TYPE
SYNTAX SEQUENCE OF Rs232InSigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A list of port input control signal entries."
::= { rs232 5 }
rs232InSigEntry OBJECT-TYPE
SYNTAX Rs232InSigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"Input control signal status for a hardware port."
INDEX { rs232InSigPortIndex, rs232InSigName }
::= { rs232InSigTable 1 }
Rs232InSigEntry ::=
SEQUENCE {
rs232InSigPortIndex
INTEGER,
rs232InSigName
INTEGER,
rs232InSigState
INTEGER,
rs232InSigChanges
Counter
}
rs232InSigPortIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The value of rs232PortIndex for the port to which
this entry belongs."
::= { rs232InSigEntry 1 }
rs232InSigName OBJECT-TYPE
SYNTAX INTEGER { rts(1), cts(2), dsr(3), dtr(4), ri(5),
dcd(6), sq(7), srs(8), srts(9),
scts(10), sdcd(11) }
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Identification of a hardware signal, as follows:
rts Request to Send
cts Clear to Send
dsr Data Set Ready
dtr Data Terminal Ready
ri Ring Indicator
dcd Received Line Signal Detector
sq Signal Quality Detector
srs Data Signaling Rate Selector
srts Secondary Request to Send
scts Secondary Clear to Send
sdcd Secondary Received Line Signal Detector
"
REFERENCE
"EIA Standard RS-232-C, August 1969."
::= { rs232InSigEntry 2 }
rs232InSigState OBJECT-TYPE
SYNTAX INTEGER { none(1), on(2), off(3) }
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The current signal state."
::= { rs232InSigEntry 3 }
rs232InSigChanges OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of times the signal has changed from
'on' to 'off' or from 'off' to 'on'."
::= { rs232InSigEntry 4 }Last bit for this part is the output signal table, and it mirrors the input one, just going the other way 🌈
-- the Output Signal table
rs232OutSigTable OBJECT-TYPE
SYNTAX SEQUENCE OF Rs232OutSigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A list of port output control signal entries."
::= { rs232 6 }
rs232OutSigEntry OBJECT-TYPE
SYNTAX Rs232OutSigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"Output control signal status for a hardware port."
INDEX { rs232OutSigPortIndex, rs232OutSigName }
::= { rs232OutSigTable 1 }
Rs232OutSigEntry ::=
SEQUENCE {
rs232OutSigPortIndex
INTEGER,
rs232OutSigName
INTEGER,
rs232OutSigState
INTEGER,
rs232OutSigChanges
Counter
}
rs232OutSigPortIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The value of rs232PortIndex for the port to which
this entry belongs."
::= { rs232OutSigEntry 1 }
rs232OutSigName OBJECT-TYPE
SYNTAX INTEGER { rts(1), cts(2), dsr(3), dtr(4), ri(5),
dcd(6), sq(7), srs(8), srts(9),
scts(10), sdcd(11) }
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Identification of a hardware signal, as follows: rts Request to Send
cts Clear to Send
dsr Data Set Ready
dtr Data Terminal Ready
ri Ring Indicator
dcd Received Line Signal Detector
sq Signal Quality Detector
srs Data Signaling Rate Selector
srts Secondary Request to Send
scts Secondary Clear to Send
sdcd Secondary Received Line Signal Detector
"
REFERENCE
"EIA Standard RS-232-C, August 1969."
::= { rs232OutSigEntry 2 }
rs232OutSigState OBJECT-TYPE
SYNTAX INTEGER { none(1), on(2), off(3) }
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The current signal state."
::= { rs232OutSigEntry 3 }
rs232OutSigChanges OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of times the signal has changed from
'on' to 'off' or from 'off' to 'on'."
::= { rs232OutSigEntry 4 }
END6. Acknowledgements 🙏
Okay, so this whole thing came out of a bunch of private MIBs 🧚 The Character MIB Working Group pulled it together, and these are the amazing people who helped make it happen 💖
- Anne Ambler, Spider
- Charles Bazaar, Emulex
- Christopher Bucci, Datability
- Anthony Chung, Hughes LAN Systems
- George Conant, Xyplex
- John Cook, Chipcom
- James Davin, MIT-LCS
- Shawn Gallagher, DEC
- Tom Grant, Xylogics
- Frank Huang, Emulex
- David Jordan, Emulex
- Satish Joshi, SynOptics
- Frank Kastenholz, Clearpoint
- Ken Key, University of Tennessee
- Jim Kinder, Fibercom
- Rajeev Kochhar, 3Com
- John LoVerso, Xylogics
- Keith McCloghrie, Hughes LAN Systems
- Donalpd Merritt, BRL
- David Perkins, 3Com
- Jim Reinstedler, Ungerman-Bass
- Marshall Rose, PSI
- Ron Strich, SSDS
- Dean Throop, DG
- Bill Townsend, Xylogics
- Jesse Walker, DEC
- David Waitzman, BBN
- Bill Westfield, cisco
7. References 📚
Here are all the sources this doc leans on, so you can go find the originals if you want to be extra 🤓
- [1] Cerf, V., "IAB Recommendations for the Development of Internet Network Management Standards", RFC 1052, NRI, April 1988.
- [2] Cerf, V., "Report of the Second Ad Hoc Network Management Review Group", RFC 1109, NRI, August 1989.
- [3] Rose M., and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based internets", RFC 1155, Performance Systems International, Hughes LAN Systems, May 1990.
- [4] McCloghrie K., and M. Rose, "Management Information Base for Network Management of TCP/IP-based internets", RFC 1156, Hughes LAN Systems, Performance Systems International, May 1990.
- [5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, Simple Network Management Protocol", RFC 1157, SNMP Research, Performance Systems International, Performance Systems International, MIT Laboratory for Computer Science, May 1990.
- [6] McCloghrie K., and M. Rose, Editors, "Management Information Base for Network Management of TCP/IP-based internets", RFC 1213, Performance Systems International, March 1991.
- [7] Information processing systems - Open Systems Interconnection - Specification of Abstract Syntax Notation One (ASN.1), International Organization for Standardization, International Standard 8824, December 1987.
- [8] Information processing systems - Open Systems Interconnection - Specification of Basic Encoding Rules for Abstract Notation One (ASN.1), International Organization for Standardization, International Standard 8825, December 1987.
- [9] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions", RFC 1212, Performance Systems International, Hughes LAN Systems, March 1991.
- [10] Rose, M., Editor, "A Convention for Defining Traps for use with the SNMP", RFC 1215, Performance Systems International, March 1991.
8. Security Considerations 💀
Okay, bestie, this one is short and sweet but also kind of a big deal 🙈 Security issues are not discussed in this memo. So if you're building on this, go find the security story somewhere else, because it is NOT here 😭
9. Author's Address 🖊️
Here's where to find the author, Bob Stewart, at Xyplex, Inc. 🦋
Bob Stewart
Xyplex, Inc.
330 Codman Hill Road
Boxborough, MA 01719
Phone: (508) 264-9900
EMail: rlstewart@eng.xyplex.com📦 where this page comes from
- ietf: rfc1317 1992-04
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms