Network Working Group F. Baker
Request for Comments: 1232 Advanced Computer Communications, Inc.
C. Kolb
Performance Systems International, Inc.
Editors
May 1991
Definitions of Managed Objects
for the DS1 Interface Type
Status of this Memo
This memo defines objects for managing DS1 Interface objects for use
with the SNMP protocol. This memo is a product of the Transmission
MIB Working Group of the Internet Engineering Task Force (IETF).
This RFC specifies an IAB standards track protocol for the Internet
community, and requests discussion and suggestions for improvements.
Please refer to the current edition of the "IAB Official Protocol
Standards" for the standardization state and status of this protocol.
Distribution of this memo is unlimited.
Table of Contents
1. Abstract .............................................. 1
2. The Network Management Framework....................... 2
3. Objects ............................................... 2
3.1 Format of Definitions ............................... 3
4. Overview .............................................. 3
4.1 Binding between Interfaces and CSUs ................. 3
4.2 Objectives of this MIB Module ....................... 4
4.3 DS1 Terminology ..................................... 4
5. Definitions ........................................... 6
5.1 The DS1 Configuration Group ......................... 6
5.2 The DS1 Interval Group .............................. 13
5.3 The DS1 Current Group ............................... 16
5.4 The DS1 Total Group ................................. 19
5.5 The DS1 Fractional Group ............................ 22
6. Acknowledgements ...................................... 25
7. References ............................................ 26
8. Security Considerations................................ 27
9. Authors' Addresses..................................... 28
1. Abstract
This memo defines an experimental portion of the Management
Information Base (MIB) for use with network management protocols in
TCP/IP-based internets. In particular, this memo defines MIB objects
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RFC 1232 DS1 Interface Objects May 1991
for representing DS1 physical interfaces. Implementors should
consult in addition to this memo the companion document that
describes that DS3 managed objects.
2. The Network Management Framework
The Internet-standard Network Management Framework consists of three
components. They are:
RFC 1155 which defines the SMI, the mechanisms used for describing
and naming objects for the purpose of management. RFC 1212
defines a more concise description mechanism, which is wholly
consistent with the SMI.
RFC 1156 which defines MIB-I, the core set of managed objects for
the Internet suite of protocols. RFC 1213, defines MIB-II, an
evolution of MIB-I based on implementation experience and new
operational requirements.
RFC 1157 which defines the SNMP, the protocol used for network
access to managed objects.
The Framework permits new objects to be defined for the purpose of
experimentation and evaluation.
3. Objects
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB are
defined using the subset of Abstract Syntax Notation One (ASN.1) [7]
defined in the SMI. In particular, each object has a name, a syntax,
and an encoding. The name is an object identifier, an
administratively assigned name, which specifies an object type. The
object type together with an object instance serves to uniquely
identify a specific instantiation of the object. For human
convenience, we often use a textual string, termed the OBJECT
DESCRIPTOR, to also refer to the object type.
The syntax of an object type defines the abstract data structure
corresponding to that object type. The ASN.1 language is used for
this purpose. However, the SMI [3] purposely restricts the ASN.1
constructs which 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 the object type's syntax. Implicitly tied to the
notion of an object type's syntax and encoding is how the object type
is represented when being transmitted on the network.
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RFC 1232 DS1 Interface Objects May 1991
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 contains the specification of all object types
contained in this MIB module. The object types are defined using the
conventions defined in the SMI, as amended by the extensions
specified in [13].
4. Overview
These objects are used when the particular media being used to
realize an interface is a DS1 physical interface. At present, this
applies to these values of the ifType variable in the Internet-
standard MIB:
ds1 (18)
e1 (19)
The definitions contained herein are based on the AT&T T-1
specifications and Extended Superframe (ESF) format [9, 10], the
latter of which conforms to proposed ANSI specifications [14, 15].
The various T1 and E1 line disciplines are similar enough that
separate MIBs are unwarranted, although there are some differences.
For example, Loss of Frame is defined more rigorously in the ESF
specification than in the D4 specification, but it is defined in
both.
4.1. Binding between Interfaces and CSUs
It should be noted that it is possible to multiplex multiple bit
streams onto a single DS1 physical interface (CSU), realizing
multiple interfaces from the perspective of the Internet-standard
MIB. It is also possible to concatenate physical interfaces to
provide a single logical interface. As such, it is important to be
able to distinguish between the indices used to identify the CSUs
attached to a node and the indices used to identify an interface (in
the MIB sense) attached to a node.
Each agent which resides on a host which uses DS1 physical interfaces
is required to assign a small, positive integer uniquely to each CSU.
This is known as the "CSUIndex", and is used to distinguish between
different CSUs attached to a node. The CSUIndex is also used as the
"key" when accessing tabular information about DS1 physical
interfaces.
The potentially many-to-one binding between CSU indices and the
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RFC 1232 DS1 Interface Objects May 1991
ifIndex value assigned to each MIB interface are defined in the
ds1ConfigTable table defined in the next section.
4.2. Objectives of this MIB Module
There are numerous things that could be included in a MIB for DS1
Interfaces: the management of multiplexors, CSUs, DSUs, and the like.
The intent of this document is to facilitate the common management of
CSUs, both in-chassis and external via proxy. As such, a design
decision was made up front to very closely align the MIB with the set
of objects that can generally be read from CSUs that are currently
deployed, which is to say ESF CSUs conforming to AT&T specifications.
However, by simple generalization of these objects, the MIB is also
made applicable to D4 and G.704 devices.
To meet a requirement not easily satisfied in other places, there is
one additional group present, the Fractional DS1 group. This is
intended to facilitate the use of fractional DS1 devices (i.e.,
devices which utilize a subset of the 8 bit channels available in the
frame) over the managed CSUs.
4.3. DS1 Terminology
The terminology used in this document to describe error conditions on
a T1 or E1 circuit monitored by a CSU are from references [10], [11],
[14], and [15].
Out of Frame event
An Out of Frame event is declared when the receiver
detects two or more framing-bit errors within a 3
millisecond period, or two or more errors out of five or
less consecutive framing-bits. At this time, the framer
enters the Out of Frame State, and starts searching for a
correct framing pattern. The Out of Frame state ends
when reframe occurs.
Loss of Signal
This event is declared upon observing 175 +/- 75
contiguous pulse positions with no pulses of either
positive or negative polarity (also called keep alive).
Code Violation Error Event
A Code Violation Error Event is the occurrence of a
received Cyclic Redundancy Check code that is not
identical to the corresponding locally-calculated code.
Bipolar Violation
A Bipolar Violation, for B8ZS-coded signals, is the
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occurrence of a received bipolar violation that is not
part of a zero-substitution code. It also includes other
error patterns such as: eight or more consecutive zeros
and incorrect parity.
Errored Seconds
An Errored Second is a second with one or more Code
Violation Error Events OR one or more Out of Frame
events. In D4 and G.704 section 2.1.3.2 (eg, G.704 which
does not implement the CRC), the presence of Bipolar
Violations also triggers an Errored Second.
Severely Errored Seconds
A Severely Errored Second is a second with 320 or more
Code Violation Error Events OR one or more Out of Frame
events.
Severely Errored Framing Second
An Severely Errored Framing Second is a second with one
or more Out of Frame events.
Unavailable Signal State
This state is declared at the onset of 10 consecutive
Severely Errored Seconds. It is cleared at the onset of
10 consecutive seconds with no Severely Errored Second.
Unavailable Seconds
Unavailable Seconds are calculated by counting the number
of seconds that the CSU is in the Unavailable Signal
State, including the initial 10 seconds to enter the
state but not including the 10 seconds to exit the state.
Note that any second that may be counted as an
Unavailable Second may not be counted as an Errored
Second, a Severely Errored Second. Since the 10 Severely
Errored Seconds that comprise the transition from the
available to Unavailable Signal State may also be counted
as Errored Seconds, and Severely Errored Seconds previous
to entering the state, these three counters are adjusted
so that any second counted during this transition is then
subtracted. The 10 seconds in the transition from
unavailable to available may be counted as Errored
Seconds.
A special case exists when the 10 or more second period
crosses the 900 second statistics window boundary, as the
foregoing description implies that the Severely Errored
Second and Unavailable Second counters must be adjusted
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RFC 1232 DS1 Interface Objects May 1991
when the Unavailable Signal State is entered. Clearly,
successive GETs of the affected ds1IntervalSES and
ds1IntervalUAS objects will return differing values if
the first GET occurs during the first few seconds of the
window. This is viewed as an unavoidable side-effect of
selecting the presently deployed AT&T objects as a basis
for this memo.
Yellow Alarm
A Yellow Alarm is declared because of an incoming Yellow
Signal from the far-end. In effect, the circuit is
declared to be a one way link.
Red Alarm
A Red Alarm is declared because of an incoming Loss of
Signal, Loss of Framing, Alarm Indication Signal. After
a Red Alarm is declared, the device sends a Yellow Signal
to the far-end. The far-end, when receives the Yellow
Signal, declares a Yellow Alarm.
Circuit Identifier
This is a character string specified by the circuit
vendor, and is useful when communicating with the vendor
during the troubleshooting process.
5. Definitions
RFC1232-MIB DEFINITIONS ::= BEGIN
IMPORTS
experimental, Counter
FROM RFC1155-SMI
DisplayString
FROM RFC1158-MIB
OBJECT-TYPE
FROM RFC-1212;
-- This MIB module uses the extended OBJECT-TYPE macro as
-- defined in [13].
-- this is the MIB module for ds1 objects
ds1 OBJECT IDENTIFIER ::= { experimental 2 }
-- the DS1 Configuration group
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-- Although the objects in this group are read-only, at the
-- agent's discretion they may be made read-write so that the
-- management station, when appropriately authorized, may
-- change the behavior of the CSU, e.g., to place the device
-- into a loopback state or emit a QRSS BER test.
-- Implementation of this group is mandatory for all systems
-- that attach to a ds1.
ds1ConfigTable OBJECT-TYPE
SYNTAX SEQUENCE OF DS1ConfigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Configuration table."
::= { ds1 1 }
ds1ConfigEntry OBJECT-TYPE
SYNTAX DS1ConfigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Configuration table."
INDEX { ds1CSUIndex }
::= { ds1ConfigTable 1 }
DS1ConfigEntry ::=
SEQUENCE {
ds1CSUIndex
INTEGER,
ds1Index
INTEGER,
ds1TimeElapsed
INTEGER (1..900),
ds1ValidIntervals
INTEGER (0..96),
ds1LineType
INTEGER,
ds1ZeroCoding
INTEGER,
ds1Loopback
INTEGER,
ds1SendCode
INTEGER,
ds1YellowAlarm
INTEGER,
ds1RedAlarm
INTEGER,
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RFC 1232 DS1 Interface Objects May 1991
ds1CircuitIdentifier
DisplayString (SIZE (0..255))
}
ds1CSUIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the CSU
to which this entry is applicable."
::= { ds1ConfigEntry 1 }
ds1Index OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"An index value that uniquely identifies an
interface to a ds1. The interface identified by a
particular value of this index is the same
interface as identified by the same value an
ifIndex object instance."
::= { ds1ConfigEntry 2 }
ds1TimeElapsed OBJECT-TYPE
SYNTAX INTEGER (1..900)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of seconds that have elapsed since the
beginning of the current error-measurement period.
Any fraction is rounded up."
::= { ds1ConfigEntry 3 }
ds1ValidIntervals OBJECT-TYPE
SYNTAX INTEGER (0..96)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of previous intervals for which valid
data was collected. The value will be 96 unless
the CSU device was brought online within the last
24 hours, in which case the value will be the
number of complete 15 minute intervals the CSU has
been online."
::= { ds1ConfigEntry 4 }
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ds1LineType OBJECT-TYPE
SYNTAX INTEGER {
other(1),
ds1ESF(2),
ds1D4(3),
ds1ANSI-ESF(4),
ds1G704(5),
ds1G704-CRC(6)
}
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable indicates the variety of DS1 Line
implementing this circuit. The type of circuit
affects the number of bits per second that the
circuit can reasonably carry, as well as the
interpretation of the usage and error statistics.
The values, in sequence, describe:
TITLE: SPECIFICATION:
ds1ESF AT&T Extended SuperFrame DS1 [10]
ds1D4 AT&T D4 format DS1 [16], [17]
ds1ANSI-ESF ANSI Extended SuperFrame format [14]
ds1G704 CCITT Recommendation G.704 [12]
(section 2.1.3.2)
ds1G704-CRC CCITT Recommendation G.704 [12]
(section 2.1.3.1)
"
::= { ds1ConfigEntry 5 }
ds1ZeroCoding OBJECT-TYPE
SYNTAX INTEGER {
ds1JammedBit(1),
ds1B8ZS(2),
ds1InvertedHDLC(3),
ds1HDB3(4),
ds1ZBTSI(5)
}
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable describes the variety of Zero Code
Suppression used on the link, which in turn
affects a number of its characteristics.
ds1JammedBit refers the Jammed bit Zero Encoding,
in which the AT&T specification of at least one
pulse every 8 bit periods is literally implemented
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RFC 1232 DS1 Interface Objects May 1991
by forcing a pulse in bit 8 of each channel.
Thus, only seven bits per channel, or 1.344 Mbps,
is available for data.
ds1B8ZS refers to the use of a specified pattern
of normal bits and bipolar violations which are
used to replace a sequence of eight zero bits (see
[14]). In this context, all eight bits in a
channel are technically available for data, but
care must be taken with D4 encoded data to avoid
having HDLC Flag streams imitate spurious Yellow
Alarm conditions. Typically, one bit per frame is
ignored to force flag streams to rotate, thereby
avoiding this error type. CCITT Recommendation
G.703 [11] may be referred to for further
definition of these.
ds1InvertedHDLC refers to the practice, common on
HDLC encoded DS1 data links, of inverting the data
between the serial interface chip and the CSU.
Since HDLC guarantees one zero every 6 bits in the
worst case, while the standards call for (in
effect) at least one pulse every eight, inverted
HDLC enjoys 4/24 one's density on the line, which
may improve the effective clock stability of a DS1
line. As with B8ZS, all eight bits in a channel
are technically available for data, but care must
be taken with D4 encoded data to avoid having HDLC
Flag streams imitate spurious Yellow Alarm
conditions. Typically, one bit per frame is
ignored to force flag streams to rotate, thereby
avoiding this error type.
ANSI Clear Channels may use ds1ZBTSI, or Zero Byte
Time Slot Interchange (see [14]).
G.704 links, with or without CRC, use ds1HDB3 (see
[11]). "
::= { ds1ConfigEntry 6 }
ds1Loopback OBJECT-TYPE
SYNTAX INTEGER {
ds1NoLoop(1),
ds1LocalLoopbackLocalSide(2),
ds1LocalLoopbackRemoteSide(3),
ds1RemoteLoopbackLocalSide(4),
ds1RemoteLoopbackRemoteSide(5)
}
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RFC 1232 DS1 Interface Objects May 1991
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable represents the loopback state of
the CSU. Devices supporting read/write access
should return badValue in response to a requested
loopback state that the CSU does not support. The
values mean:
ds1NoLoop
Not in the loopback state. A device that is
not capable of performing a loopback on either
interface shall always return this as it's
value.
ds1LocalLoopbackLocalSide
Signal received from the local side of the
device is looped back at the local connector
(eg, without involving the CSU).
ds1LocalLoopbackRemoteSide
Signal received from the local side of the
device is looped back at the remote connector
(eg, through the CSU).
ds1RemoteLoopbackLocalSide
Signal received from the remote side of the
device is looped back at the local connector
(eg, through the CSU).
ds1RemoteLoopbackRemoteSide
Signal received from the remote side of the
device is looped back at the remote connector
(eg, without involving the CSU)."
::= { ds1ConfigEntry 7 }
ds1SendCode OBJECT-TYPE
SYNTAX INTEGER {
ds1OtherTest(1),
ds1SendNoCode(2),
ds1SendSetCode(3),
ds1SendResetCode(4),
ds1SendQRSS(5)
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RFC 1232 DS1 Interface Objects May 1991
}
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable indicates what type of code is
being sent across the DS1 circuit by the CSU. The
values mean:
ds1SendNoCode sending looped or normal data
ds1SendSetCode sending a loopback request
ds1SendResetCode sending a loopback termination request
ds1SendQRSS sending the BERT pattern described in
ANSI T1.403-1989 section 5.6
ds1OtherTest sending a different BERT/BLERT pattern,
such as all zeroes, all ones, etc."
::= { ds1ConfigEntry 8 }
ds1YellowAlarm OBJECT-TYPE
SYNTAX INTEGER {
ds1NoYellowAlarm (1),
ds1YellowAlarm (2)
}
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable indicates if a Yellow Alarm
condition exists.
Note that G.704 interfaces do not support Yellow
Alarms. Accordingly, such agents should return
the value ds1NoYellowAlarm."
::= { ds1ConfigEntry 9 }
ds1RedAlarm OBJECT-TYPE
SYNTAX INTEGER {
ds1NoRedAlarm (1),
ds1RedAlarm (2)
}
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable indicates if a Red Alarm condition
exists.
Note that G.704 interfaces do not support Red
Alarms. Accordingly, such agents should return
the value ds1NoRedAlarm."
::= { ds1ConfigEntry 10 }
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RFC 1232 DS1 Interface Objects May 1991
ds1CircuitIdentifier OBJECT-TYPE
SYNTAX DisplayString (SIZE (0..255))
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable contains the transmission vendor's
circuit identifier, for the purpose of
facilitating troubleshooting."
::= { ds1ConfigEntry 11 }
-- the DS1 Interval group
-- Implementation of this group is mandatory for all systems
-- that attach to a ds1.
-- It is recognized that some currently deployed CSUs do not
-- record the entire set of statistics specified in this
-- group. Accordingly, some agents queried for these objects
-- may treat these objects as having an ACCESS clause value
-- of not-accessible.
-- The DS1 Interval Table contains various statistics
-- collected by each CSU over the previous 24 hours of
-- operation. The past 24 hours are broken into 96 completed
-- 15 minute intervals.
ds1IntervalTable OBJECT-TYPE
SYNTAX SEQUENCE OF DS1IntervalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Interval table."
::= { ds1 2 }
ds1IntervalEntry OBJECT-TYPE
SYNTAX DS1IntervalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Interval table."
INDEX { ds1IntervalIndex, ds1IntervalNumber }
::= { ds1IntervalTable 1 }
DS1IntervalEntry ::=
SEQUENCE {
ds1IntervalIndex
INTEGER,
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RFC 1232 DS1 Interface Objects May 1991
ds1IntervalNumber
INTEGER (1..96),
ds1IntervalESs
Counter,
ds1IntervalSESs
Counter,
ds1IntervalSEFSs
Counter,
ds1IntervalUASs
Counter,
ds1IntervalCSSs
Counter,
ds1IntervalBPVs
Counter,
ds1IntervalCVs
Counter
}
ds1IntervalIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the CSU
to which this entry is applicable. The interface
identified by a particular value of this index is
the same interface as identified by the same value
an ds1CSUIndex object instance."
::= { ds1IntervalEntry 1 }
ds1IntervalNumber OBJECT-TYPE
SYNTAX INTEGER (1..96)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"A number between 1 and 96, where 1 is the most
recently completed 15 minute interval and 96 is
the least recently completed 15 minute interval
(assuming that all 96 intervals are valid)."
::= { ds1IntervalEntry 2 }
ds1IntervalESs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Errored
Seconds, as defined by ANSI Draft Standard
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RFC 1232 DS1 Interface Objects May 1991
T1M1.3/90 - 027R2[15], encountered by a DS1 CSU
during one of the previous 96 fifteen minute
intervals."
::= { ds1IntervalEntry 3 }
ds1IntervalSESs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Severely Errored Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU during one of the previous 96 fifteen
minute intervals."
::= { ds1IntervalEntry 4 }
ds1IntervalSEFSs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Severely Errored Framing Seconds, as defined by
ANSI Draft Standard T1M1.3/90 - 027R2[15],
encountered by a DS1 CSU during one of the
previous 96 fifteen minute intervals."
::= { ds1IntervalEntry 5 }
ds1IntervalUASs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Unavailable Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU during one of the previous 96 fifteen
minute intervals."
::= { ds1IntervalEntry 6 }
ds1IntervalCSSs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Controlled Slip Seconds, as defined by ANSI Draft
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RFC 1232 DS1 Interface Objects May 1991
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU during one of the previous 96 fifteen
minute intervals."
::= { ds1IntervalEntry 7 }
ds1IntervalBPVs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Bipolar
Violations, as defined by ANSI Draft Standard
T1M1.3/90 - 027R2[15], encountered by a DS1 CSU
during one of the previous 96 fifteen minute
intervals."
::= { ds1IntervalEntry 8 }
ds1IntervalCVs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Code
Violation Error Events, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU during one of the previous 96 fifteen
minute intervals.
Note that D4 and G.704 (section 2.1.3.2)
interfaces do not support Code Violation Error
Events. Accordingly, such agents may treat this
object as having an ACCESS clause value of not-
accessible."
::= { ds1IntervalEntry 9 }
-- the DS1 Current group
-- Implementation of this group is mandatory for all systems
-- that attach to a ds1.
-- It is recognized that some currently deployed CSUs do not
-- record the entire set of statistics specified in this
-- group. Accordingly, some agents queried for these objects
-- may treat these objects as having an ACCESS clause value
-- of not-accessible.
-- The DS1 current table contains various statistics being
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RFC 1232 DS1 Interface Objects May 1991
-- collected for the current 15 minute interval.
ds1CurrentTable OBJECT-TYPE
SYNTAX SEQUENCE OF DS1CurrentEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Current table."
::= { ds1 3 }
ds1CurrentEntry OBJECT-TYPE
SYNTAX DS1CurrentEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Current table."
INDEX { ds1CurrentIndex }
::= { ds1CurrentTable 1 }
DS1CurrentEntry ::=
SEQUENCE {
ds1CurrentIndex
INTEGER,
ds1CurrentESs
Counter,
ds1CurrentSESs
Counter,
ds1CurrentSEFSs
Counter,
ds1CurrentUASs
Counter,
ds1CurrentCSSs
Counter,
ds1CurrentBPVs
Counter,
ds1CurrentCVs
Counter
}
ds1CurrentIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the CSU
to which this entry is applicable. The interface
identified by a particular value of this index is
the same interface as identified by the same value
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RFC 1232 DS1 Interface Objects May 1991
an ds1CSUIndex object instance."
::= { ds1CurrentEntry 1 }
ds1CurrentESs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Errored
Seconds, as defined by ANSI Draft Standard
T1M1.3/90 - 027R2[15], encountered by a DS1 CSU in
the current 15 minute interval."
::= { ds1CurrentEntry 2 }
ds1CurrentSESs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Severely Errored Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the current 15 minute interval."
::= { ds1CurrentEntry 3 }
ds1CurrentSEFSs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Severely Errored Framing Seconds, as defined by
ANSI Draft Standard T1M1.3/90 - 027R2[15],
encountered by a DS1 CSU in the current 15 minute
interval."
::= { ds1CurrentEntry 4 }
ds1CurrentUASs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Unavailable Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the current 15 minute interval."
::= { ds1CurrentEntry 5 }
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RFC 1232 DS1 Interface Objects May 1991
ds1CurrentCSSs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Controlled Slip Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the current 15 minute interval."
::= { ds1CurrentEntry 6 }
ds1CurrentBPVs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Bipolar
Violations, as defined by ANSI Draft Standard
T1M1.3/90 - 027R2[15], encountered by a DS1 CSU in
the current 15 minute interval."
::= { ds1CurrentEntry 7 }
ds1CurrentCVs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Code
Violation Error Events, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the current 15 minute interval.
Note that D4 and G.704 (section 2.1.3.2)
interfaces do not support Code Violation Error
Events. Accordingly, such agents may treat this
object as having an ACCESS clause value of not-
accessible."
::= { ds1CurrentEntry 8 }
-- the DS1 Total group
-- Implementation of this group is mandatory for all systems
-- that attach to a ds1.
-- It is recognized that some currently deployed CSUs do not
-- record the entire set of statistics specified in this
-- group. Accordingly, some agents queried for these objects
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RFC 1232 DS1 Interface Objects May 1991
-- may treat these objects as having an ACCESS clause value
-- of not-accessible.
-- The DS1 Total Table contains the cumulative sum of the
-- various statistics for the 24 hour interval preceding the
-- first valid interval in the ds1CurrentTable.
ds1TotalTable OBJECT-TYPE
SYNTAX SEQUENCE OF DS1TotalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Total table. 24 hour interval."
::= { ds1 4 }
ds1TotalEntry OBJECT-TYPE
SYNTAX DS1TotalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Total table."
INDEX { ds1TotalIndex }
::= { ds1TotalTable 1 }
DS1TotalEntry ::=
SEQUENCE {
ds1TotalIndex
INTEGER,
ds1TotalESs
Counter,
ds1TotalSESs
Counter,
ds1TotalSEFSs
Counter,
ds1TotalUASs
Counter,
ds1TotalCSSs
Counter,
ds1TotalBPVs
Counter,
ds1TotalCVs
Counter
}
ds1TotalIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
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RFC 1232 DS1 Interface Objects May 1991
DESCRIPTION
"The index value which uniquely identifies the CSU
to which this entry is applicable. The interface
identified by a particular value of this index is
the same interface as identified by the same value
an ds1CSUIndex object instance."
::= { ds1TotalEntry 1 }
ds1TotalESs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Errored
Seconds, as defined by ANSI Draft Standard
T1M1.3/90 - 027R2[15], encountered by a DS1 CSU in
the previous 24 hour interval"
::= { ds1TotalEntry 2 }
ds1TotalSESs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Severely Errored Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the previous 24 hour interval."
::= { ds1TotalEntry 3 }
ds1TotalSEFSs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Severely Errored Framing Seconds, as defined by
ANSI Draft Standard T1M1.3/90 - 027R2[15],
encountered by a DS1 CSU in the previous 24 hour
interval."
::= { ds1TotalEntry 4 }
ds1TotalUASs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Transmission MIB Working Group [Page 21]
RFC 1232 DS1 Interface Objects May 1991
Unavailable Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the previous 24 hour interval."
::= { ds1TotalEntry 5 }
ds1TotalCSSs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of
Controlled Slip Seconds, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the previous 24 hour interval."
::= { ds1TotalEntry 6 }
ds1TotalBPVs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Bipolar
Violations, as defined by ANSI Draft Standard
T1M1.3/90 - 027R2[15], encountered by a DS1 CSU in
the previous 24 hour interval."
::= { ds1TotalEntry 7 }
ds1TotalCVs OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The counter associated with the number of Code
Violation Error Events, as defined by ANSI Draft
Standard T1M1.3/90 - 027R2[15], encountered by a
DS1 CSU in the previous 24 hour interval.
Note that D4 and G.704 (section 2.1.3.2)
interfaces do not support Code Violation Error
Events. Accordingly, such agents may treat this
object as having an ACCESS clause value of not-
accessible."
::= { ds1TotalEntry 8 }
-- the DS1 Fractional group
-- Implementation of this group is mandatory for those
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RFC 1232 DS1 Interface Objects May 1991
-- systems utilizing a fractional DS1 capability
-- The DS1 fractional table contains identifies which DS1
-- channels associated with a CSU are being used to support a
-- logical interface, i.e., an entry in the interfaces table
-- from the Internet-standard MIB. For Clear Channel
-- implementations, exactly one ifTable entry corresponds to
-- the CSU being managed. In this very typical case, the
-- variable ds1Index indicates the value of ifIndex which
-- corresponds to the interface being supported by a
-- particular CSU.
-- However, for fractional DS1 implementations, the
-- correspondent value of ds1Index is 0, and for each DS1
-- channel supporting a logical interface, there is an entry
-- in the DS1 fractional table which names a value for
-- ifIndex.
--
-- For ds1ESF, ds1D4, and ds1ANSI-ESF, there are 24 legal
-- channels, numbered 1 through 24.
--
-- For G.704, there are 32 legal channels, numbered 1
-- through 32. ds1G704 can carry user data in channels 2
-- through 32, channel 1 being an overhead channel.
-- ds1G704-CRC can carry user data in channels 2 through
-- 16 and 18 through 32, channels 1 and 17 being overhead
-- channels.
ds1FracTable OBJECT-TYPE
SYNTAX SEQUENCE OF DS1FracEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Fractional table."
::= { ds1 5 }
ds1FracEntry OBJECT-TYPE
SYNTAX DS1FracEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Fractional table."
INDEX { ds1FracIndex, ds1FracNumber }
::= { ds1FracTable 1 }
DS1FracEntry ::=
SEQUENCE {
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RFC 1232 DS1 Interface Objects May 1991
ds1FracIndex
INTEGER,
ds1FracNumber
INTEGER (1..32),
ds1FracIfIndex
INTEGER
}
ds1FracIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the CSU
to which this entry is applicable. The interface
identified by a particular value of this index is
the same interface as identified by the same value
an ds1CSUIndex object instance."
::= { ds1FracEntry 1 }
ds1FracNumber OBJECT-TYPE
SYNTAX INTEGER (1..32)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The channel number for this entry."
::= { ds1FracEntry 2 }
ds1FracIfIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"An index value that uniquely identifies an
interface to a ds1. The interface identified by a
particular value of this index is the same
interface as identified by the same value an
ifIndex object instance."
::= { ds1FracEntry 3 }
END
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RFC 1232 DS1 Interface Objects May 1991
6. Acknowledgements
This document was produced by the SNMP and the Transmission MIB
Working Groups:
Anne Ambler, Spider
Karl Auerbach, Sun
Fred Baker, ACC
Ken Brinkerhoff
Ron Broersma, NOSC
Jack Brown, US Army
Theodore Brunner, Bellcore
Jeffrey Buffum, HP
Jeffrey D. Case, UTK
Chris Chiptasso, Spartacus
Paul Ciarfella, DEC
Bob Collet
Tracy Cox, Bellcore
James R. Davin, MIT-LCS
Kurt Dobbins, Cabletron
Nadya El-Afandi, Network Systems
Gary Ellis, HP
Fred Engle
Mike Erlinger
Richard Fox, Synoptics
Karen Frisa, CMU
Chris Gunner, DEC
Ken Hibbard, Xylogics
Ole Jacobsen, Interop
Ken Jones
Satish Joshi, Synoptics
Frank Kastenholz, Racal-Interlan
Shimshon Kaufman, Spartacus
Jim Kinder, Fibercom
Alex Koifman, BBN
Christopher Kolb, PSI
Cheryl Krupczak, NCR
Peter Lin, Vitalink
John Lunny, TWG
Carl Malamud
Keith McCloghrie, HLS
Donna McMaster, David Systems
Lynn Monsanto, Sun
Dave Perkins, 3COM
Jim Reinstedler, Ungerman Bass
Anil Rijsinghani, DEC
Kary Robertson
Marshall T. Rose, PSI (chair)
Transmission MIB Working Group [Page 25]
RFC 1232 DS1 Interface Objects May 1991
L. Michael Sabo, NCSC
Jon Saperia, DEC
John Seligson
Fei Shu, NEC
Sam Sjogren, TGV
Mark Sleeper, Sparta
Lance Sprung
Mike St.Johns
Bob Stewart, Xyplex
Emil Sturniold
Kaj Tesink, Bellcore
Dean Throop, Data General
Bill Townsend, Xylogics
Maurice Turcotte
Kannan Varadhou
Sudhanshu Verma, HP
Warren Vik, Interactive Systems
David Waitzman, BBN
Steve Waldbusser, CMU
Dan Wintringhan
David Wood
Jeff Young, Cray Research
7. References
[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.
Transmission MIB Working Group [Page 26]
RFC 1232 DS1 Interface Objects May 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] AT&T Information Systems, AT&T ESF DS1 Channel Service Unit
User's Manual, 999-100-305, February 1988.
[10] AT&T Technical Reference, Requirements for Interfacing Digital
Terminal Equipment to Services Employing the Extended Superframe
Format, Publication 54016, May 1988.
[11] CCITT Specifications Volume III, Recommendation G.703,
Physical/Electrical Characteristics of Hierarchical Digital
Interfaces, July 1988.
[12] CCITT Specifications Volume III, Recommendation G.704,
Synchronous frame structures used at primary and secondary
hierarchical levels, July 1988.
[13] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
RFC 1212, Performance Systems International, Hughes LAN Systems,
March 1991.
[14] ANSI T1.403-1989 American National Standard for
Telecommunications -- Carrier-to-Customer Installation -- DS1
Metallic Interface.
[15] ANSI T1M1.3/90 - 027R2 Draft Proposed Standard -- Description of
Installation and Maintenance Parameters for Digital Circuits,
Facilities, and Networks.
[16] Bell System Techical Reference, Publication 62411, High Capacity
Digital Service Channel Interface Specification, September 1983.
[17] Bell System Technical Reference, Publication 43801, "Digital
Channel Bank Requirements and Objectives", November 1982.
8. Security Considerations
Security issues are not discussed in this memo.
Transmission MIB Working Group [Page 27]
RFC 1232 DS1 Interface Objects May 1991
9. Authors' Addresses
Fred Baker
Advanced Computer Communications, Inc.
720 Santa Barbara Street
Santa Barbara, California 93101
Phone: (805) 963 9431
EMail: fbaker@acc.com
Christopher P. Kolb
Performance Systems International, Inc.
Reston International Center
11800 Sunrise Valley Drive
Suite 1100
Reston, VA 22091
Phone: (703) 620-6651
EMail: kolb@psi.com
Transmission MIB Working Group [Page 28]
RFC, FYI, BCP