Network Working Group F. Baker

Network Working Group F. Baker
Request for Comments: 1406 Advanced Computer Communications
Obsoletes: 1232 J. Watt
Newbridge Networks Corporation
Editors
January 1993

Definitions of Managed Objects for the DS1 and E1 Interface Types

Status of this Memo

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.

Abstract

This memo defines a portion of the Management Information Base (MIB)
for use with network management protocols in TCP/IP-based internets.
In particular, it defines objects for managing DS1 Interfaces --
including both T1 and E1 (a.k.a., CEPT 2 Mbit/s) links.

This document entirely replaces RFC 1232, which contains a
fundamental error: many objects are encoded as Counters that must be
encoded as INTEGERs or Gauges. The magnitude of the change required
is sufficient that virtually every object changed. Therefore, the
MIB documented in RFC 1232 should not be implemented.

Table of Contents

1. The Network Management Framework ...................... 2
2. Objects ............................................... 2
2.1 Format of Definitions ................................ 3
2.2 Changes from RFC 1232 ................................ 3
3. Overview .............................................. 4
3.1 Binding between ifIndex and DS1 Interfaces ........... 5
3.2 Objectives of this MIB Module ........................ 7
3.3 DS1 Terminology ...................................... 7
3.3.1 Error Events ....................................... 7
3.3.2 Performance Defects ................................ 8
3.3.3 Performance Parameters ............................. 9
3.3.4 Failure States ..................................... 11
3.3.5 Other Terms ........................................ 13
4. Definitions ........................................... 14
4.1 DS1 Near End Group ................................... 14

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4.1.1 DS1 Configuration Table ............................ 14
4.1.2 DS1 Current Table .................................. 22
4.1.3 DS1 Interval Table ................................. 26
4.1.4 DS1 Total Table .................................... 30
4.2 DS1 Far End Group .................................... 33
4.2.1 DS1 Far End Current Table .......................... 34
4.2.2 DS1 Far End Interval Table ......................... 38
4.2.3 DS1 Far End Total Table ............................ 41
4.3 DS1 Fractional Group ................................. 45
4.3.1 DS1 Fractional Table ............................... 45
5. Acknowledgements ...................................... 47
6. References ............................................ 48
7. Security Considerations ............................... 50
8. Authors' Addresses .................................... 50

1. The Network Management Framework

The Internet-standard Network Management Framework consists of three
components. They are:

STD 16/RFC 1155 [1] which defines the SMI, the mechanisms used for
describing and naming objects for the purpose of management. STD
16/RFC 1212 [2] defines a more concise description mechanism,
which is wholly consistent with the SMI.

RFC 1156 [3] which defines MIB-I, the core set of managed objects
for the Internet suite of protocols. STD 17/RFC 1213 [4] defines
MIB-II, an evolution of MIB-I based on implementation experience
and new operational requirements.

STD 15/RFC 1157 [5] 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.

2. 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) [6]
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.

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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 [1] 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.

The SMI specifies the use of the basic encoding rules of ASN.1 [7],
subject to the additional requirements imposed by the SNMP.

2.1. Format of Definitions

Section 4 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 STD 16, RFC 1212 [2].

2.2. Changes from RFC 1232

The changes from RFC 1232 are the following:

(1) This MIB module contains three groups: DS1 Near End Group
which is mandatory, DS1 Far End Group which is optional,
and the Fractional Table, which is optional.

(2) The Far End Group is a new group and contains statistics
that are collected from the far end DS1 interface. The
Far End Group may only be implemented by DS1 systems that
use the facilities data link to exchange this information
- both T1.403 and PUB 54016 define ways to exchange this
information over data links; vendors may use other
proprietary means to do this on various link types.

(3) ds1CSUIndex has been renamed dsx1LineIndex. This object
is the identifier of a DS1 Interface on a device. On a
CSU, a single DS1 data stream will cross two DS1
interfaces, which have separate dsx1LineIndex values.

(4) ds1Index has been renamed dsx1IfIndex. This value for
this object is equal to the value of ifIndex from the
Interfaces table of MIB II (STD 17, RFC 1213).

(5) an object has been added (dsx1TransmitClockSource) to
indicate the source of transmit clock.

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(6) The ACCESS for objects in the dsx1ConfigTable has been
set to read-write for items that are configurable.

(7) Description of test configurations has changed. A new
object has been added called dsx1LoopbackConfig, which
better describes the loopback capabilities of a DS1
interface on a device.

(8) The description of line alarm status has changed. A new
object has been added called dsx1LineStatus. This object
better describes the status (e.g., failure state and
loopback state) of a DS1 interface.

(9) All Counters have been changed to Gauges.

(10) Information about how applications might use the zero
code suppression have been removed; only the actual line
coding algorithm is described. For clarity the object
was thus renamed to dsx1LineCoding.

(11) A Line Errored Seconds object has been added to all near
end tables and the count of Bipolar Violations (BPVs) was
changed to a count of Line Code Violations (LCVs).

(12) Bursty Errored Seconds (a.k.a., Errored Seconds Type B)
and Degraded Minutes objects have been added to all near
end tables.

(13) The Coding Violation error event is now referred to as a
Path Coding Violation (PCV) Error Event.

3. 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 Superframe
(a.k.a., D4) and Extended Superframe (ESF) formats [8, 9], the latter
of which conforms to ANSI specifications [10], and the CCITT
Recommendations [11, 12], referred to as E1 for the rest of this
memo.

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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.

Where it is necessary to distinguish between the flavors of E1 with
and without CRC, E1-CRC to denotes the "with CRC" form (G.704 Table
4b) and E1-noCRC denotes the "without CRC" form (G.704 Table 4a).

3.1. Binding between ifIndex and DS1 Interfaces

Different physical configurations for the support of SNMP with DS1
equipment exist. To accommodate these scenarios, two different
indices for DS1 interfaces are introduced in this MIB. These indices
are dsx1IfIndex and dsx1LineIndex.

External interface scenario: the SNMP Agent represents all managed
DS1 lines as external interfaces (for example, an Agent residing on
the device supporting DS1 interfaces directly):

For this scenario, all interfaces are assigned an integer value equal
to ifIndex, and the following applies:

ifIndex=dsx1IfIndex=dsx1LineIndex for all interfaces.

The dsx1IfIndex column of the DS1 Configuration table relates each
DS1 interface to its corresponding interface (ifIndex) in the
Internet-standard MIB (MIB-II STD 17, RFC 1213).

External & Internal interface scenario: the SNMP Agents resides on an
host external from the device supporting DS1 interfaces (e.g., a
router). The Agent represents both the host and the DS1 device. The
index dsx1LineIndex is used to not only represent the DS1 interfaces
external from the host/DS1-device combination, but also the DS1
interfaces connecting the host and the DS1 device. The index
dsx1IfIndex is always equal to ifIndex.

Example:

A shelf full of CSUs connected to a Router. An SNMP Agent residing
on the router proxies for itself and the CSU. The router has also an
Ethernet interface:

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+-----+
| | |
| | | +---------------------+
|E | | 1.544 MBPS | Line#A | DS1 Link
|t | R |---------------+ - - - - - - - - - +------>
|h | | | |
|e | O | 1.544 MBPS | Line#B | DS1 Link
|r | |---------------+ - - - - - - - - - - +------>
|n | U | | CSU Shelf |
|e | | 1.544 MBPS | Line#C | DS1 Link
|t | T |---------------+ - - - -- -- - - - - +------>
| | | | |
|-----| E | 1.544 MBPS | Line#D | DS1 Link
| | |---------------+ - - - - -- - - - - +------>
| | R | |_____________________|
| | |
| +-----+

The assignment of the index values could for example be:

ifIndex (= dsx1IfIndex) dsx1LineIndex
1 NA NA (Ethernet)
2 Line#A Router Side 6
2 Line#A Network Side 7
3 Line#B Router Side 8
3 Line#B Network Side 9
4 Line#C Router Side 10
4 Line#C Network Side 11
5 Line#D Router Side 12
5 Line#D Network Side 13

For this example, ifNumber is equal to 5. Note the following
description of dsx1LineIndex: the dsx1LineIndex identifies a DS1
Interface on a managed device. If there is an ifEntry that is
directly associated with this and only this DS1 interface, it should
have the same value as ifIndex. Otherwise, number the
dsx1LineIndices with an unique identifier following the rules of
choosing a number greater than ifNumber and numbering inside
interfaces (e.g., equipment side) with even numbers and outside
interfaces (e.g., network side) with odd numbers.

If the CSU shelf is managed by itself by a local SNMP Agent, the
situation would be:

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ifIndex (= dsx1IfIndex) dsx1LineIndex
2 Line#A Router Side 2
1 Line#A Network Side 1
4 Line#B Router Side 4
3 Line#B Network Side 3
6 Line#C Router Side 6
5 Line#C Network Side 5
8 Line#D Router Side 8
7 Line#D Network Side 7

3.2. Objectives of this MIB Module

There are numerous things that could be included in a MIB for DS1
signals: the management of multiplexors, CSUs, DSUs, and the like.
The intent of this document is to facilitate the common management of
all devices with DS1 interfaces. 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 DS1 devices that are currently deployed.

3.3. DS1 Terminology

The terminology used in this document to describe error conditions on
a DS1 interface as monitored by a DS1 device are based on the
definitions from the ANSI T1M1.3/92-005R1 draft standard [13]. If
the definition in this document does not match the definition in the
ANSI T1M1.3/92-005R1 draft document, the implementer should follow
the definition described in this document.

3.3.1. Error Events

Bipolar Violation (BPV) Error Event
A BPV error event for an AMI-coded signal is the
occurrence of a pulse of the same polarity as the
previous pulse. A BPV error event for a B8ZS- or HDB3-
coded signal is the occurrence of a pulse of the same
polarity as the previous pulse without being a part of
the zero substitution code.

Excessive Zeroes (EXZ) Error Event
An Excessive Zeroes error event for an AMI-coded signal
is the occurrence of more than fifteen contiguous zeroes.
For a B8ZS coded signal, the defect occurs when more than
seven contiguous zeroes are detected.

Line Coding Violation (LCV) Error Event
A Line Coding Violation (LCV) is the occurrence of either
a Bipolar Violation (BPV) or Excessive Zeroes (EXZ) Error
Event.

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Path Coding Violation (PCV) Error Event
A Path Coding Violation error event is a frame
synchronization bit error in the D4 and E1-noCRC formats,
or a CRC error in the ESF and E1-CRC formats.

Controlled Slip (CS) Error Event
A Controlled Slip is the replication or deletion of the
payload bits of a DS1 frame. A Controlled Slip may be
performed when there is a difference between the timing
of a synchronous receiving terminal and the received
signal. A Controlled Slip does not cause an Out of Frame
defect.

3.3.2. Performance Defects

Out Of Frame (OOF) Defect
An OOF defect is the occurrence of a particular density
of Framing Error events.

For T1 links, an Out of Frame defect is declared when the
receiver detects two or more framing errors within a 3
msec period for ESF signals and 0.75 msec for D4 signals,
or two or more errors out of five or fewer consecutive
framing-bits.

For E1 links, an Out Of Frame defect is declared when
three consecutive frame alignment signals have been
received with an error (see G.706 Section 4.1 [17]).

Once an Out Of Frame Defect is declared, the framer
starts searching for a correct framing pattern. The Out
of Frame defect ends when the signal is in frame.

In-frame occurs when there are fewer than two frame bit
errors within 3 msec period for ESF signals and 0.75 msec
for D4 signals.

For E1 links, in-frame occurs when a) in frame N the
frame alignment signal is correct and b) in frame N+1 the
frame alignment signal is absent (i.e., bit 2 in TS0 is a
one) and c) in frame N+2 the frame alignment signal is
present and correct.

Alarm Indication Signal (AIS) Defect
For D4 and ESF links, the 'all ones' condition is
detected at a DS1 line interface upon observing an
unframed signal with a one's density of at least 99.9%
present for a time equal to or greater than T, where 3 ms

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<= T <= 75 ms. The AIS is terminated upon observing a
signal not meeting the one's density or the unframed
signal criteria for a period equal to or greater than
than T.

For E1 links, the 'all-ones' condition is detected at the
line interface as a string of 512 bits containing fewer
than three zero bits (see O.162 [14] Section 3.3.2).

3.3.3. Performance Parameters

All performance parameters are accumulated in fifteen minute
intervals and up to 96 intervals (24 hours worth) are kept by an
agent. Fewer than 96 intervals of data will be available if the
agent has been restarted within the last 24 hours. In addition,
there is a rolling 24-hour total of each performance parameter.

There is no requirement for an agent to ensure fixed relationship
between the start of a fifteen minute interval and any wall clock;
however some agents may align the fifteen minute intervals with
quarter hours.

Line Errored Seconds (LES)
A Line Errored Second, according to T1M1.3, is a second
in which one or more Line Code Violation error events
were detected.

While many implementations are currently unable to detect
the zero strings, it is expected that interface
manufacturers will add this capability in deference to
ANSI; therefore, it will become available in time.

In the T1M1.3 specification, near end Line Code
Violations and far end Line Errored Seconds are counted.
For consistency, we count Line Errored Seconds at both
ends.

Controlled Slip Seconds (CSS)
A Controlled Slip Second is a one-second interval
containing one or more controlled slips.

Errored Seconds (ES)
For ESF and E1-CRC links an Errored Second is a second
with one or more Path Code Violations OR one or more Out
of Frame defects OR one or more Controlled Slip events OR
a detected AIS defect.

For D4 and E1-noCRC links, the presence of Bipolar

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Violations also triggers an Errored Second.

This is not incremented during an Unavailable Second.

Bursty Errored Seconds (BES)
A Bursty Errored Second (also known as Errored Second
type B) is a second with fewer than 320 and more than 1
Path Coding Violation error events, no Severely Errored
Frame defects and no detected incoming AIS defects.
Controlled slips are not included in this parameter.

This is not incremented during an Unavailable Second.

Severely Errored Seconds (SES)
A Severely Errored Second for ESF signals is a second
with 320 or more Path Code Violation Error Events OR one
or more Out of Frame defects OR a detected AIS defect.

For E1-CRC signals, a Severely Errored Second is a second
with 832 or more Path Code Violation error events OR one
or more Out of Frame defects.

For E1-noCRC signals, a Severely Errored Second is a 2048
LCVs or more.

For D4 signals, a Severely Errored Second is a count of
one-second intervals with Framing Error events, or an OOF
defect, or 1544 LCVs or more.

Controlled slips are not included in this parameter.

This is not incremented during an Unavailable Second.

Severely Errored Framing Second (SEFS)
An Severely Errored Framing Second is a second with one
or more Out of Frame defects OR a detected AIS defect.

Degraded Minutes
A Degraded Minute is one in which the estimated error
rate exceeds 1E-6 but does not exceed 1E-3 (see G.821
[15]).

Degraded Minutes are determined by collecting all of the
Available Seconds, removing any Severely Errored Seconds
grouping the result in 60-second long groups and counting
a 60-second long group (a.k.a., minute) as degraded if the
cumulative errors during the seconds present in the group
exceed 1E-6. Available seconds are merely those seconds

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which are not Unavailable as described below.

Unavailable Seconds (UAS)
Unavailable Seconds (UAS) are calculated by counting the
number of seconds that the interface is unavailable. The
DS1 interface is said to be unavailable from the onset of
10 contiguous SESs, or the onset of the condition leading
to a failure (see Failure States). If the condition
leading to the failure was immediately preceded by one or
more contiguous SESs, then the DS1 interface
unavailability starts from the onset of these SESs. Once
unavailable, and if no failure is present, the DS1
interface becomes available at the onset of 10 contiguous
seconds with no SESs. Once unavailable, and if a failure
is present, the DS1 interface becomes available at the
onset of 10 contiguous seconds with no SESs, if the
failure clearing time is less than or equal to 10
seconds. If the failure clearing time is more than 10
seconds, the DS1 interface becomes available at the onset
of 10 contiguous seconds with no SESs, or the onset
period leading to the successful clearing condition,
whichever occurs later. With respect to the DS1 error
counts, all counters are incremented while the DS1
interface is deemed available. While the interface is
deemed unavailable, the only count that is incremented is
UASs.

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
when the Unavailable Signal State is entered. Clearly,
successive GETs of the affected dsx1IntervalSESs and
dsx1IntervalUASs 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 defined managed objects as a
basis for this memo.

3.3.4. Failure States

The following failure states are received, or detected failures, that
are reported in the dsx1LineStatus object. When a DS1 interface
would, if ever, produce the conditions leading to the failure state
is described in the appropriate specification.

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Far End Alarm Failure
The Far End Alarm failure is also known as "Yellow Alarm"
in the T1 case and "Distant Alarm" in the E1 case.

For D4 links, the Far End Alarm failure is declared when
bit 6 of all channels has been zero for at least 335 ms
and is cleared when bit 6 of at least one channel is
non-zero for a period T, where T is usually less than one
second and always less than 5 seconds. The Far End Alarm
failure is not declared for D4 links when a Loss of
Signal is detected.

For ESF links, the Far End Alarm failure is declared if
the Yellow Alarm signal pattern occurs in at least seven
out of ten contiguous 16-bit pattern intervals and is
cleared if the Yellow Alarm signal pattern does not occur
in ten contiguous 16-bit signal pattern intervals.

For E1 links, the Far End Alarm failure is declared when
bit 3 of time-slot zero is received set to one on two
consecutive occasions. The Far End Alarm failure is
cleared when bit 3 of time-slot zero is received set to
zero.

Alarm Indication Signal (AIS) Failure
The Alarm Indication Signal failure is declared when an
AIS defect is detected at the input and the AIS defect
still exists after the Loss Of Frame failure (which is
caused by the unframed nature of the 'all-ones' signal)
is declared. The AIS failure is cleared when the Loss Of
Frame failure is cleared.

Loss Of Frame Failure
For T1 links, the Loss Of Frame failure is declared when
an OOF or LOS defect has persisted for T seconds, where
2 <= T <= 10. The Loss Of Frame failure is cleared when
there have been no OOF or LOS defects during a period T
where 0 <= T <= 20. Many systems will perform "hit
integration" within the period T before declaring or
clearing the failure e.g., see TR 62411 [16].

For E1 links, the Loss Of Frame Failure is declared when
an OOF defect is detected.

Loss Of Signal Failure
For T1, the Loss Of Signal failure is declared upon
observing 175 +/- 75 contiguous pulse positions with no
pulses of either positive or negative polarity. The LOS

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failure is cleared upon observing an average pulse
density of at least 12.5% over a period of 175 +/- 75
contiguous pulse positions starting with the receipt of a
pulse.

For E1 links, the Loss Of Signal failure is declared when
greater than 10 consecutive zeroes are detected (see
O.162 Section 3.4.4).

Loopback Pseudo-Failure
The Loopback Pseudo-Failure is declared when the near end
equipment has placed a loopback (of any kind) on the DS1.
This allows a management entity to determine from one
object whether the DS1 can be considered to be in service
or not (from the point of view of the near end
equipment).

TS16 Alarm Indication Signal Failure
For E1 links, the TS16 Alarm Indication Signal failure is
declared when time-slot 16 is received as all ones for
all frames of two consecutive multiframes (see G.732
Section 4.2.6). This condition is never declared for T1.

Loss Of MultiFrame Failure
The Loss Of MultiFrame failure is declared when two
consecutive multiframe alignment signals (bits 4 through
7 of TS16 of frame 0) have been received with an error.
The Loss Of Multiframe failure is cleared when the first
correct multiframe alignment signal is received. The
Loss Of Multiframe failure can only be declared for E1
links operating with G.732 [18] framing (sometimes called
"Channel Associated Signalling" mode).

Far End Loss Of Multiframe Failure
The Far End Loss Of Multiframe failure is declared when
bit 2 of TS16 of frame 0 is received set to one on two
consecutive occasions. The Far End Loss Of Multiframe
failure is cleared when bit 2 of TS16 of frame 0 is
received set to zero. The Far End Loss Of Multiframe
failure can only be declared for E1 links operating in
"Channel Associated Signalling" mode.

3.3.5. Other Terms

Circuit Identifier
This is a character string specified by the circuit
vendor, and is useful when communicating with the vendor
during the troubleshooting process.

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4. Definitions

RFC1406-MIB DEFINITIONS ::= BEGIN
IMPORTS
Gauge
FROM RFC1155-SMI
transmission, DisplayString
FROM RFC1213-MIB
OBJECT-TYPE
FROM RFC-1212;

-- This MIB module uses the extended OBJECT-TYPE macro as
-- defined in RFC 1212.

-- this is the MIB module for the DS1 objects

ds1 OBJECT IDENTIFIER ::= { transmission 18 }

-- note that this subsumes cept (19); there is no separate CEPT MIB

-- The DS1 Near End Group

-- Implementation of this group is mandatory for all systems
-- that attach to a DS1 Interface.

-- The DS1 Near End Group consists of four tables:
-- DS1 Configuration
-- DS1 Current
-- DS1 Interval
-- DS1 Total

-- the DS1 Configuration Table

dsx1ConfigTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1ConfigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Configuration table."
::= { ds1 6 }

dsx1ConfigEntry OBJECT-TYPE
SYNTAX Dsx1ConfigEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION

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"An entry in the DS1 Configuration table."
INDEX { dsx1LineIndex }
::= { dsx1ConfigTable 1 }

Dsx1ConfigEntry ::=
SEQUENCE {
dsx1LineIndex
INTEGER,
dsx1IfIndex
INTEGER,
dsx1TimeElapsed
INTEGER,
dsx1ValidIntervals
INTEGER,
dsx1LineType
INTEGER,
dsx1LineCoding
INTEGER,
dsx1SendCode
INTEGER,
dsx1CircuitIdentifier
DisplayString,
dsx1LoopbackConfig
INTEGER,
dsx1LineStatus
INTEGER,
dsx1SignalMode
INTEGER,
dsx1TransmitClockSource
INTEGER,
dsx1Fdl
INTEGER
}

dsx1LineIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This object is the identifier of a DS1 Inter-
face on a managed device. If there is an ifEn-
try that is directly associated with this and
only this DS1 interface, it should have the
same value as ifIndex. Otherwise, the value
exceeds ifNumber, and is a unique identifier
following this rule: inside interfaces (e.g.,
equipment side) with even numbers and outside
interfaces (e.g., network side) with odd

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numbers."
::= { dsx1ConfigEntry 1 }

dsx1IfIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This value for this object is equal to the
value of ifIndex from the Interfaces table of
MIB II (RFC 1213)."
::= { dsx1ConfigEntry 2 }

dsx1TimeElapsed OBJECT-TYPE
SYNTAX INTEGER (0..899)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of seconds that have elapsed since
the beginning of the current error-measurement
period."
::= { dsx1ConfigEntry 3 }

dsx1ValidIntervals 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 interface was brought on-line within
the last 24 hours, in which case the value will
be the number of complete 15 minute intervals
the since interface has been online."
::= { dsx1ConfigEntry 4 }

dsx1LineType OBJECT-TYPE
SYNTAX INTEGER {
other(1),
dsx1ESF(2),
dsx1D4(3),
dsx1E1(4),
dsx1E1-CRC(5),
dsx1E1-MF(6),

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RFC 1406 DS1/E1 MIB January 1993

dsx1E1-CRC-MF(7)
}
ACCESS read-write
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:
dsx1ESF Extended SuperFrame DS1
dsx1D4 AT&T D4 format DS1
dsx1E1 CCITT Recommendation G.704
(Table 4a)
dsx1E1-CRC CCITT Recommendation G.704
(Table 4b)
dsxE1-MF G.704 (Table 4a) with TS16
multiframing enabled
dsx1E1-CRC-MF G.704 (Table 4b) with TS16
multiframing enabled"

::= { dsx1ConfigEntry 5 }

dsx1LineCoding OBJECT-TYPE
SYNTAX INTEGER {
dsx1JBZS (1),
dsx1B8ZS (2),
dsx1HDB3 (3),
dsx1ZBTSI (4),
dsx1AMI (5),
other(6)
}
ACCESS read-write
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.

dsx1JBZS refers the Jammed Bit Zero Suppres-
sion, in which the AT&T specification of at
least one pulse every 8 bit periods is literal-
ly implemented by forcing a pulse in bit 8 of
each channel. Thus, only seven bits per chan-

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RFC 1406 DS1/E1 MIB January 1993

nel, or 1.344 Mbps, is available for data.

dsx1B8ZS refers to the use of a specified pat-
tern of normal bits and bipolar violations
which are used to replace a sequence of eight
zero bits.

ANSI Clear Channels may use dsx1ZBTSI, or Zero
Byte Time Slot Interchange.

E1 links, with or without CRC, use dsx1HDB3 or
dsx1AMI.

dsx1AMI refers to a mode wherein no zero code
suppression is present and the line encoding
does not solve the problem directly. In this
application, the higher layer must provide data
which meets or exceeds the pulse density re-
quirements, such as inverting HDLC data."
::= { dsx1ConfigEntry 6 }

dsx1SendCode OBJECT-TYPE
SYNTAX INTEGER {
dsx1SendNoCode(1),
dsx1SendLineCode(2),
dsx1SendPayloadCode(3),
dsx1SendResetCode(4),
dsx1SendQRS(5),
dsx1Send511Pattern(6),
dsx1Send3in24Pattern(7),
dsx1SendOtherTestPattern(8)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"This variable indicates what type of code is
being sent across the DS1 interface by the dev-
ice. The values mean:

dsx1SendNoCode
sending looped or normal data

dsx1SendLineCode
sending a request for a line loopback

dsx1SendPayloadCode
sending a request for a payload loopback

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RFC 1406 DS1/E1 MIB January 1993

dsx1SendResetCode
sending a loopback termination request

dsx1SendQRS
sending a Quasi-Random Signal (QRS) test
pattern

dsx1Send511Pattern
sending a 511 bit fixed test pattern

dsx1Send3in24Pattern
sending a fixed test pattern of 3 bits set
in 24

dsx1SendOtherTestPattern
sending a test pattern other than those
described by this object"
::= { dsx1ConfigEntry 7 }

dsx1CircuitIdentifier OBJECT-TYPE
SYNTAX DisplayString (SIZE (0..255))
ACCESS read-write
STATUS mandatory
DESCRIPTION
"This variable contains the transmission
vendor's circuit identifier, for the purpose of
facilitating troubleshooting."
::= { dsx1ConfigEntry 8 }

dsx1LoopbackConfig OBJECT-TYPE
SYNTAX INTEGER {
dsx1NoLoop(1),
dsx1PayloadLoop(2),
dsx1LineLoop(3),
dsx1OtherLoop(4)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"This variable represents the loopback confi-
guration of the DS1 interface. Agents support-
ing read/write access should return badValue in
response to a requested loopback state that the
interface does not support. The values mean:

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RFC 1406 DS1/E1 MIB January 1993

dsx1NoLoop
Not in the loopback state. A device that
is not capable of performing a loopback on
the interface shall always return this as
it's value.

dsx1PayloadLoop
The received signal at this interface is
looped through the device. Typically the
received signal is looped back for re-
transmission after it has passed through
the device's framing function.

dsx1LineLoop
The received signal at this interface does
not go through the device (minimum pene-
tration) but is looped back out.

dsx1OtherLoop
Loopbacks that are not defined here."
::= { dsx1ConfigEntry 9 }

dsx1LineStatus OBJECT-TYPE
SYNTAX INTEGER (1..8191)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"This variable indicates the Line Status of the
interface. It contains loopback, failure, re-
ceived 'alarm' and transmitted 'alarm' infor-
mation.

The dsx1LineStatus is a bit map represented as a sum,
therefore, it can represent multiple failures (alarms) and
a LoopbackState simultaneously.

dsx1NoAlarm should be set if and only if no other flag is
set.

If the dsx1LoopbackState bit is set, the loopback in ef-
fect can be determined from the dsx1LoopbackConfig object.

The various bit positions are:
1 dsx1NoAlarm No Alarm Present
2 dsx1RcvFarEndLOF Far end LOF (a.k.a., Yellow Alarm)
4 dsx1XmtFarEndLOF Near end sending LOF Indication
8 dsx1RcvAIS Far end sending AIS

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RFC 1406 DS1/E1 MIB January 1993

16 dsx1XmtAIS Near end sending AIS
32 dsx1LossOfFrame Near end LOF (a.k.a., Red Alarm)
64 dsx1LossOfSignal Near end Loss Of Signal
128 dsx1LoopbackState Near end is looped
256 dsx1T16AIS E1 TS16 AIS
512 dsx1RcvFarEndLOMF Far End Sending TS16 LOMF
1024 dsx1XmtFarEndLOMF Near End Sending TS16 LOMF
2048 dsx1RcvTestCode Near End detects a test code
4096 dsx1OtherFailure any line status not defined here"
::= { dsx1ConfigEntry 10 }

dsx1SignalMode OBJECT-TYPE
SYNTAX INTEGER {
none (1),
robbedBit (2),
bitOriented (3),
messageOriented (4)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"'none' indicates that no bits are reserved for
signaling on this channel.

'robbedBit' indicates that T1 Robbed Bit Sig-
naling is in use.

'bitOriented' indicates that E1 Channel Asso-
ciated Signaling is in use.

'messageOriented' indicates that Common Chan-
nel Signaling is in use either on channel 16 of
an E1 link or channel 24 of a T1."
::= { dsx1ConfigEntry 11 }

dsx1TransmitClockSource OBJECT-TYPE
SYNTAX INTEGER {
loopTiming (1),
localTiming (2),
throughTiming (3)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The source of Tranmit Clock.

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RFC 1406 DS1/E1 MIB January 1993

'loopTiming' indicates that the recovered re-
ceive clock is used as the transmit clock.

'localTiming' indicates that a local clock
source is used.

'throughTiming' indicates that recovered re-
ceive clock from another interface is used as
the transmit clock."
::= { dsx1ConfigEntry 12 }

dsx1Fdl OBJECT-TYPE
SYNTAX INTEGER {
other(1),
dsx1Ansi-T1-403(2),
dsx1Att-54016(4),
dsx1Fdl-none(8)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"This bitmap describes the use of the facili-
ties data link, and is the sum of the capabili-
ties:

'other' indicates that a protocol other than
one following is used.

'dsx1Ansi-T1-403' refers to the FDL exchange
recommended by ANSI.

'dsx1Att-54016' refers to ESF FDL exchanges.

'dsx1Fdl-none' indicates that the device does
not use the FDL."
::= { dsx1ConfigEntry 13 }

-- the DS1 Current Table

-- The DS1 current table contains various statistics being
-- collected for the current 15 minute interval.

dsx1CurrentTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1CurrentEntry
ACCESS not-accessible
STATUS mandatory

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RFC 1406 DS1/E1 MIB January 1993

DESCRIPTION
"The DS1 Current table."
::= { ds1 7 }

dsx1CurrentEntry OBJECT-TYPE
SYNTAX Dsx1CurrentEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Current table."
INDEX { dsx1CurrentIndex }
::= { dsx1CurrentTable 1 }

Dsx1CurrentEntry ::=
SEQUENCE {
dsx1CurrentIndex
INTEGER,
dsx1CurrentESs
Gauge,
dsx1CurrentSESs
Gauge,
dsx1CurrentSEFSs
Gauge,
dsx1CurrentUASs
Gauge,
dsx1CurrentCSSs
Gauge,
dsx1CurrentPCVs
Gauge,
dsx1CurrentLESs
Gauge,
dsx1CurrentBESs
Gauge,
dsx1CurrentDMs
Gauge,
dsx1CurrentLCVs
Gauge
}

dsx1CurrentIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface to which this entry is applica-
ble. The interface identified by a particular

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RFC 1406 DS1/E1 MIB January 1993

value of this index is the same interface as
identified by the same value as a dsx1LineIndex
object instance."
::= { dsx1CurrentEntry 1 }

dsx1CurrentESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Errored Seconds, encountered by
a DS1 interface in the current 15 minute inter-
val."
::= { dsx1CurrentEntry 2 }

dsx1CurrentSESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Severely Errored Seconds encoun-
tered by a DS1 interface in the current 15
minute interval."
::= { dsx1CurrentEntry 3 }

dsx1CurrentSEFSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Severely Errored Framing Seconds
encountered by a DS1 interface in the current
15 minute interval."
::= { dsx1CurrentEntry 4 }

dsx1CurrentUASs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Unavailable Seconds encountered
by a DS1 interface in the current 15 minute in-
terval."
::= { dsx1CurrentEntry 5 }

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RFC 1406 DS1/E1 MIB January 1993

dsx1CurrentCSSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Controlled Slip Seconds encoun-
tered by a DS1 interface in the current 15
minute interval."
::= { dsx1CurrentEntry 6 }

dsx1CurrentPCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Path Coding Violations encoun-
tered by a DS1 interface in the current 15
minute interval."
::= { dsx1CurrentEntry 7 }

dsx1CurrentLESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Line Errored Seconds encountered
by a DS1 interface in the current 15 minute in-
terval."
::= { dsx1CurrentEntry 8 }

dsx1CurrentBESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Bursty Errored Seconds (BESs)
encountered by a DS1 interface in the current
15 minute interval."
::= {dsx1CurrentEntry 9 }

dsx1CurrentDMs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory

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RFC 1406 DS1/E1 MIB January 1993

DESCRIPTION
"The number of Degraded Minutes (DMs) encoun-
tered by a DS1 interface in the current 15
minute interval."
::= { dsx1CurrentEntry 10 }

dsx1CurrentLCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Line Code Violations (LCVs) en-
countered by a DS1 interface in the current 15
minute interval."
::= {dsx1CurrentEntry 11 }

-- the DS1 Interval

-- The DS1 Interval Table contains various statistics
-- collected by each DS1 Interface over the previous 24 hours of
-- operation. The past 24 hours are broken into 96 completed
-- 15 minute intervals.

dsx1IntervalTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1IntervalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Interval table."
::= { ds1 8 }

dsx1IntervalEntry OBJECT-TYPE
SYNTAX Dsx1IntervalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Interval table."
INDEX { dsx1IntervalIndex, dsx1IntervalNumber }
::= { dsx1IntervalTable 1 }

Dsx1IntervalEntry ::=
SEQUENCE {
dsx1IntervalIndex
INTEGER,
dsx1IntervalNumber

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RFC 1406 DS1/E1 MIB January 1993

INTEGER,
dsx1IntervalESs
Gauge,
dsx1IntervalSESs
Gauge,
dsx1IntervalSEFSs
Gauge,
dsx1IntervalUASs
Gauge,
dsx1IntervalCSSs
Gauge,
dsx1IntervalPCVs
Gauge,
dsx1IntervalLESs
Gauge,
dsx1IntervalBESs
Gauge,
dsx1IntervalDMs
Gauge,
dsx1IntervalLCVs
Gauge
}

dsx1IntervalIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface to which this entry is applica-
ble. The interface identified by a particular
value of this index is the same interface as
identified by the same value as a dsx1LineIndex
object instance."
::= { dsx1IntervalEntry 1 }

dsx1IntervalNumber 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 minutes inter-
val (assuming that all 96 intervals are
valid)."
::= { dsx1IntervalEntry 2 }

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RFC 1406 DS1/E1 MIB January 1993

dsx1IntervalESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Errored Seconds encountered by a
DS1 interface in one of the previous 96, indi-
vidual 15 minute, intervals."
::= { dsx1IntervalEntry 3 }

dsx1IntervalSESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Severely Errored Seconds encoun-
tered by a DS1 interface in one of the previous
96, individual 15 minute, intervals."
::= { dsx1IntervalEntry 4 }

dsx1IntervalSEFSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Severely Errored Framing Seconds
encountered by a DS1 interface in one of the
previous 96, individual 15 minute, intervals."
::= { dsx1IntervalEntry 5 }

dsx1IntervalUASs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Unavailable Seconds encountered
by a DS1 interface in one of the previous 96,
individual 15 minute, intervals."
::= { dsx1IntervalEntry 6 }

dsx1IntervalCSSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory

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RFC 1406 DS1/E1 MIB January 1993

DESCRIPTION
"The number of Controlled Slip Seconds encoun-
tered by a DS1 interface in one of the previous
96, individual 15 minute, intervals."
::= { dsx1IntervalEntry 7 }

dsx1IntervalPCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Path Coding Violations encoun-
tered by a DS1 interface in one of the previous
96, individual 15 minute, intervals."
::= { dsx1IntervalEntry 8 }

dsx1IntervalLESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Line Errored Seconds encountered
by a DS1 interface in one of the previous 96,
individual 15 minute, intervals."
::= { dsx1IntervalEntry 9 }

dsx1IntervalBESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Bursty Errored Seconds (BESs)
encountered by a DS1 interface in one of the
previous 96, individual 15 minute, intervals."
::= {dsx1IntervalEntry 10 }

dsx1IntervalDMs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Degraded Minutes (DMs) encoun-
tered by a DS1 interface in one of the previous
96, individual 15 minute, intervals."

Trunk MIB Working Group [Page 29]

RFC 1406 DS1/E1 MIB January 1993

::= { dsx1IntervalEntry 11 }

dsx1IntervalLCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Line Code Violations (LCVs) en-
countered by a DS1 interface in the current 15
minute interval."
::= {dsx1IntervalEntry 12 }

-- the DS1 Total

-- The DS1 Total Table contains the cumulative sum of the
-- various statistics for the 24 hour period preceding the
-- current interval.

dsx1TotalTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1TotalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Total table. 24 hour interval."
::= { ds1 9 }

dsx1TotalEntry OBJECT-TYPE
SYNTAX Dsx1TotalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Total table."
INDEX { dsx1TotalIndex }
::= { dsx1TotalTable 1 }

Dsx1TotalEntry ::=
SEQUENCE {
dsx1TotalIndex
INTEGER,
dsx1TotalESs
Gauge,
dsx1TotalSESs
Gauge,
dsx1TotalSEFSs
Gauge,

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RFC 1406 DS1/E1 MIB January 1993

dsx1TotalUASs
Gauge,
dsx1TotalCSSs
Gauge,
dsx1TotalPCVs
Gauge,
dsx1TotalLESs
Gauge,
dsx1TotalBESs
Gauge,
dsx1TotalDMs
Gauge,
dsx1TotalLCVs
Gauge
}

dsx1TotalIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface to which this entry is applica-
ble. The interface identified by a particular
value of this index is the same interface as
identified by the same value as a dsx1LineIndex
object instance."
::= { dsx1TotalEntry 1 }

dsx1TotalESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Errored Seconds encountered by a
DS1 interface in the previous 24 hour interval"
::= { dsx1TotalEntry 2 }

dsx1TotalSESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Severely Errored Seconds encoun-
tered by a DS1 interface in the previous 24
hour interval."

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RFC 1406 DS1/E1 MIB January 1993

::= { dsx1TotalEntry 3 }

dsx1TotalSEFSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Severely Errored Framing Seconds
encountered by a DS1 interface in the previous
24 hour interval."
::= { dsx1TotalEntry 4 }

dsx1TotalUASs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Unavailable Seconds encountered
by a DS1 interface in the previous 24 hour in-
terval."
::= { dsx1TotalEntry 5 }

dsx1TotalCSSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Controlled Slip Seconds encoun-
tered by a DS1 interface in the previous 24
hour interval."
::= { dsx1TotalEntry 6 }

dsx1TotalPCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Path Coding Violations encoun-
tered by a DS1 interface in the previous 24
hour interval."
::= { dsx1TotalEntry 7 }

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RFC 1406 DS1/E1 MIB January 1993

dsx1TotalLESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Line Errored Seconds encountered
by a DS1 interface in the previous 24 hour in-
terval."
::= { dsx1TotalEntry 8 }

dsx1TotalBESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Bursty Errored Seconds (BESs)
encountered by a DS1 interface in the previous
24 hour interval."
::= { dsx1TotalEntry 9 }

dsx1TotalDMs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Degraded Minutes (DMs) encoun-
tered by a DS1 interface in the previous 24
hour interval."
::= { dsx1TotalEntry 10 }

dsx1TotalLCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Line Code Violations (LCVs) en-
countered by a DS1 interface in the current 15
minute interval."
::= {dsx1TotalEntry 11 }

-- The DS1 Far End Group

-- Implementation of this group is optional for all systems
-- that attach to a DS1 Interface.

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RFC 1406 DS1/E1 MIB January 1993

-- The DS1 Far End Group consists of three tables:
-- DS1 Far End Current
-- DS1 Far End Interval
-- DS1 Far End Total

-- The DS1 Far End Current Table

-- The DS1 Far End Current table contains various statistics
-- being collected for the current 15 minute interval.
-- The statistics are collected from the far end messages on the
-- Facilities Data Link. The definitions are the same as
-- described for the near-end information.

dsx1FarEndCurrentTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1FarEndCurrentEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Far End Current table."
::= { ds1 10 }

dsx1FarEndCurrentEntry OBJECT-TYPE
SYNTAX Dsx1FarEndCurrentEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Far End Current table."
INDEX { dsx1FarEndCurrentIndex }
::= { dsx1FarEndCurrentTable 1 }

Dsx1FarEndCurrentEntry ::=
SEQUENCE {
dsx1FarEndCurrentIndex
INTEGER,
dsx1FarEndTimeElapsed
INTEGER,
dsx1FarEndValidIntervals
INTEGER,
dsx1FarEndCurrentESs
Gauge,
dsx1FarEndCurrentSESs
Gauge,
dsx1FarEndCurrentSEFSs
Gauge,
dsx1FarEndCurrentUASs
Gauge,
dsx1FarEndCurrentCSSs

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RFC 1406 DS1/E1 MIB January 1993

Gauge,
dsx1FarEndCurrentLESs
Gauge,
dsx1FarEndCurrentPCVs
Gauge,
dsx1FarEndCurrentBESs
Gauge,
dsx1FarEndCurrentDMs
Gauge
}

dsx1FarEndCurrentIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface to which this entry is applica-
ble. The interface identified by a particular
value of this index is the same interface as
identified by the same value an dsx1LineIndex
object instance."
::= { dsx1FarEndCurrentEntry 1 }

dsx1FarEndTimeElapsed OBJECT-TYPE
SYNTAX INTEGER (0..899)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of seconds that have elapsed
since the beginning of the far end current
error-measurement period."
::= { dsx1FarEndCurrentEntry 2 }

dsx1FarEndValidIntervals OBJECT-TYPE
SYNTAX INTEGER (0..96)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of previous far end intervals
for which valid data was collected. The
value will be 96 unless the interface was
brought online within the last 24 hours,
in which case the value will be the number
of complete 15 minute far end intervals
since the interface has been online."

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RFC 1406 DS1/E1 MIB January 1993

::= { dsx1FarEndCurrentEntry 3 }

dsx1FarEndCurrentESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far Far End Errored Seconds en-
countered by a DS1 interface in the current 15
minute interval."
::= { dsx1FarEndCurrentEntry 4 }

dsx1FarEndCurrentSESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Severely Errored Seconds
encountered by a DS1 interface in the current
15 minute interval."
::= { dsx1FarEndCurrentEntry 5 }

dsx1FarEndCurrentSEFSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Severely Errored Framing
Seconds encountered by a DS1 interface in the
current 15 minute interval."
::= { dsx1FarEndCurrentEntry 6 }

dsx1FarEndCurrentUASs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Unavailable Seconds encountered
by a DS1 interface in the current 15 minute in-
terval."
::= { dsx1FarEndCurrentEntry 7 }

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RFC 1406 DS1/E1 MIB January 1993

dsx1FarEndCurrentCSSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Controlled Slip Seconds
encountered by a DS1 interface in the current
15 minute interval."
::= { dsx1FarEndCurrentEntry 8 }

dsx1FarEndCurrentLESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Line Errored Seconds en-
countered by a DS1 interface in the current 15
minute interval."
::= { dsx1FarEndCurrentEntry 9 }

dsx1FarEndCurrentPCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Path Coding Violations
reported via the far end block error count en-
countered by a DS1 interface in the current 15
minute interval."
::= { dsx1FarEndCurrentEntry 10 }

dsx1FarEndCurrentBESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Bursty Errored Seconds (BESs)
encountered by a DS1 interface in the current
15 minute interval."
::= {dsx1FarEndCurrentEntry 11 }

dsx1FarEndCurrentDMs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only

Trunk MIB Working Group [Page 37]

RFC 1406 DS1/E1 MIB January 1993

STATUS mandatory
DESCRIPTION
"The number of Degraded Minutes (DMs) encoun-
tered by a DS1 interface in the current 15
minute interval."
::= { dsx1FarEndCurrentEntry 12 }

-- The DS1 Far End Interval Table

-- The DS1 Far End Interval Table contains various statistics
-- collected by each DS1 interface over the previous 24 hours of
-- operation. The past 24 hours are broken into 96
-- completed 15 minute intervals.

dsx1FarEndIntervalTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1FarEndIntervalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Far End Interval table."
::= { ds1 11 }

dsx1FarEndIntervalEntry OBJECT-TYPE
SYNTAX Dsx1FarEndIntervalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Far End Interval table."
INDEX { dsx1FarEndIntervalIndex,
dsx1FarEndIntervalNumber }
::= { dsx1FarEndIntervalTable 1 }

Dsx1FarEndIntervalEntry ::=
SEQUENCE {
dsx1FarEndIntervalIndex
INTEGER,
dsx1FarEndIntervalNumber
INTEGER,
dsx1FarEndIntervalESs
Gauge,
dsx1FarEndIntervalSESs
Gauge,
dsx1FarEndIntervalSEFSs
Gauge,
dsx1FarEndIntervalUASs
Gauge,

Trunk MIB Working Group [Page 38]

RFC 1406 DS1/E1 MIB January 1993

dsx1FarEndIntervalCSSs
Gauge,
dsx1FarEndIntervalLESs
Gauge,
dsx1FarEndIntervalPCVs
Gauge,
dsx1FarEndIntervalBESs
Gauge,
dsx1FarEndIntervalDMs
Gauge
}

dsx1FarEndIntervalIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface to which this entry is applica-
ble. The interface identified by a particular
value of this index is the same interface as
identified by the same value as a dsx1LineIndex
object instance."
::= { dsx1FarEndIntervalEntry 1 }

dsx1FarEndIntervalNumber 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 minutes inter-
val (assuming that all 96 intervals are
valid)."
::= { dsx1FarEndIntervalEntry 2 }

dsx1FarEndIntervalESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Errored Seconds encoun-
tered by a DS1 interface in one of the previous
96, individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 3 }

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RFC 1406 DS1/E1 MIB January 1993

dsx1FarEndIntervalSESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Severely Errored Seconds
encountered by a DS1 interface in one of the
previous 96, individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 4 }

dsx1FarEndIntervalSEFSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Severely Errored Framing
Seconds encountered by a DS1 interface in one
of the previous 96, individual 15 minute, in-
tervals."
::= { dsx1FarEndIntervalEntry 5 }

dsx1FarEndIntervalUASs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Unavailable Seconds encountered
by a DS1 interface in one of the previous 96,
individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 6 }

dsx1FarEndIntervalCSSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Controlled Slip Seconds
encountered by a DS1 interface in one of the
previous 96, individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 7 }

dsx1FarEndIntervalLESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only

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RFC 1406 DS1/E1 MIB January 1993

STATUS mandatory
DESCRIPTION
"The number of Far End Line Errored Seconds en-
countered by a DS1 interface in one of the pre-
vious 96, individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 8 }

dsx1FarEndIntervalPCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Path Coding Violations
reported via the far end block error count en-
countered by a DS1 interface in one of the pre-
vious 96, individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 9 }

dsx1FarEndIntervalBESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Bursty Errored Seconds (BESs)
encountered by a DS1 interface in one of the
previous 96, individual 15 minute, intervals."
::= {dsx1FarEndIntervalEntry 10 }

dsx1FarEndIntervalDMs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Degraded Minutes (DMs) encoun-
tered by a DS1 interface in one of the previous
96, individual 15 minute, intervals."
::= { dsx1FarEndIntervalEntry 11 }

-- The DS1 Far End Total Table

-- The DS1 Far End Total Table contains the cumulative sum of the
-- various statistics for the 24 hour period preceding the
-- current interval.

Trunk MIB Working Group [Page 41]

RFC 1406 DS1/E1 MIB January 1993

dsx1FarEndTotalTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1FarEndTotalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Far End Total table."
::= { ds1 12 }

dsx1FarEndTotalEntry OBJECT-TYPE
SYNTAX Dsx1FarEndTotalEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Far End Total table."
INDEX { dsx1FarEndTotalIndex }
::= { dsx1FarEndTotalTable 1 }

Dsx1FarEndTotalEntry ::=
SEQUENCE {
dsx1FarEndTotalIndex
INTEGER,
dsx1FarEndTotalESs
Gauge,
dsx1FarEndTotalSESs
Gauge,
dsx1FarEndTotalSEFSs
Gauge,
dsx1FarEndTotalUASs
Gauge,
dsx1FarEndTotalCSSs
Gauge,
dsx1FarEndTotalLESs
Gauge,
dsx1FarEndTotalPCVs
Gauge,
dsx1FarEndTotalBESs
Gauge,
dsx1FarEndTotalDMs
Gauge
}

dsx1FarEndTotalIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the

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RFC 1406 DS1/E1 MIB January 1993

DS1 interface to which this entry is applica-
ble. The interface identified by a particular
value of this index is the same interface as
identified by the same value an dsx1LineIndex
object instance."
::= { dsx1FarEndTotalEntry 1 }

dsx1FarEndTotalESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Errored Seconds encoun-
tered by a DS1 interface in the previous 24
hour interval."
::= { dsx1FarEndTotalEntry 2 }

dsx1FarEndTotalSESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Severely Errored Seconds
encountered by a DS1 interface in the previous
24 hour interval."
::= { dsx1FarEndTotalEntry 3 }

dsx1FarEndTotalSEFSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Severely Errored Framing
Seconds encountered by a DS1 interface in the
previous 24 hour interval."
::= { dsx1FarEndTotalEntry 4 }

dsx1FarEndTotalUASs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Unavailable Seconds encountered
by a DS1 interface in the previous 24 hour in-

Trunk MIB Working Group [Page 43]

RFC 1406 DS1/E1 MIB January 1993

terval."
::= { dsx1FarEndTotalEntry 5 }

dsx1FarEndTotalCSSs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Controlled Slip Seconds
encountered by a DS1 interface in the previous
24 hour interval."
::= { dsx1FarEndTotalEntry 6 }

dsx1FarEndTotalLESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Line Errored Seconds en-
countered by a DS1 interface in the previous 24
hour interval."
::= { dsx1FarEndTotalEntry 7 }

dsx1FarEndTotalPCVs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Far End Path Coding Violations
reported via the far end block error count en-
countered by a DS1 interface in the previous 24
hour interval."
::= { dsx1FarEndTotalEntry 8 }

dsx1FarEndTotalBESs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Bursty Errored Seconds (BESs)
encountered by a DS1 interface in the previous
24 hour interval."
::= { dsx1FarEndTotalEntry 9 }

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RFC 1406 DS1/E1 MIB January 1993

dsx1FarEndTotalDMs OBJECT-TYPE
SYNTAX Gauge
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of Degraded Minutes (DMs) encoun-
tered by a DS1 interface in the previous 24
hour interval."
::= { dsx1FarEndTotalEntry 10 }

-- the DS1 Fractional Group

-- Implementation of this group is mandatory for those
-- systems dividing a DS1 into channels containing different
-- data streams that are of local interest. Systems which
-- are indifferent to data content, such as CSUs, need not
-- implement it.

-- The DS1 fractional table 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 example, consider an application managing a North
-- American ISDN Primary Rate link whose division is a 384 kbit/s
-- H1 "B" Channel for Video, a second H1 for data to a primary
-- routing peer, and 12 64 kbit/s H0 "B" Channels. Consider that
-- some subset of the H0 channels are used for voice and the
-- remainder are available for dynamic data calls.

-- we count a total of 14 interfaces multiplexed onto the DS1
-- interface. Six DS1 channels (for the sake of the example,
-- channels 1..6) are used for Video, six more (7..11 and 13)
-- are used for data, and the remaining 12 are are in channels
-- 12 and 14..24.

-- Let us further imagine that ifIndex 2 is of type DS1 and
-- refers to the DS1 interface, and that the interfaces layered
-- onto it are numbered 3..16.

-- We might describe the allocation of channels, in the
-- dsx1FracTable, as follows:

-- dsx1FracIfIndex.2. 1 = 3 dsx1FracIfIndex.2.13 = 4
-- dsx1FracIfIndex.2. 2 = 3 dsx1FracIfIndex.2.14 = 6
-- dsx1FracIfIndex.2. 3 = 3 dsx1FracIfIndex.2.15 = 7
-- dsx1FracIfIndex.2. 4 = 3 dsx1FracIfIndex.2.16 = 8

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RFC 1406 DS1/E1 MIB January 1993

-- dsx1FracIfIndex.2. 5 = 3 dsx1FracIfIndex.2.17 = 9
-- dsx1FracIfIndex.2. 6 = 3 dsx1FracIfIndex.2.18 = 10
-- dsx1FracIfIndex.2. 7 = 4 dsx1FracIfIndex.2.19 = 11
-- dsx1FracIfIndex.2. 8 = 4 dsx1FracIfIndex.2.20 = 12
-- dsx1FracIfIndex.2. 9 = 4 dsx1FracIfIndex.2.21 = 13
-- dsx1FracIfIndex.2.10 = 4 dsx1FracIfIndex.2.22 = 14
-- dsx1FracIfIndex.2.11 = 4 dsx1FracIfIndex.2.23 = 15
-- dsx1FracIfIndex.2.12 = 5 dsx1FracIfIndex.2.24 = 16

-- For North American (DS1) interfaces, there are 24 legal
-- channels, numbered 1 through 24.

-- For G.704 interfaces, there are 31 legal channels,
-- numbered 1 through 31. The channels (1..31) correspond
-- directly to the equivalently numbered time-slots.

dsx1FracTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dsx1FracEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"The DS1 Fractional table."
::= { ds1 13 }

dsx1FracEntry OBJECT-TYPE
SYNTAX Dsx1FracEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"An entry in the DS1 Fractional table."
INDEX { dsx1FracIndex, dsx1FracNumber }
::= { dsx1FracTable 1 }

Dsx1FracEntry ::=
SEQUENCE {
dsx1FracIndex
INTEGER,
dsx1FracNumber
INTEGER,
dsx1FracIfIndex
INTEGER
}

dsx1FracIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)

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RFC 1406 DS1/E1 MIB January 1993

ACCESS read-only
STATUS mandatory
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface to which this entry is applica-
ble. The interface identified by a particular
value of this index is the same interface as
identified by the same value an dsx1LineIndex
object instance."
::= { dsx1FracEntry 1 }

dsx1FracNumber OBJECT-TYPE
SYNTAX INTEGER (1..31)
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The channel number for this entry."
::= { dsx1FracEntry 2 }

dsx1FracIfIndex OBJECT-TYPE
SYNTAX INTEGER (1..'7fffffff'h)
ACCESS read-write
STATUS mandatory
DESCRIPTION
"An index value that uniquely identifies an in-
terface. The interface identified by a partic-
ular value of this index is the same interface
as identified by the same value an ifIndex ob-
ject instance. If no interface is currently us-
ing a channel, the value should be zero. If a
single interface occupies more than one time
slot, that ifIndex value will be found in mul-
tiple time slots."
::= { dsx1FracEntry 3 }

END

5. Acknowledgements

This document was produced by the Trunk MIB Working Group:

Tracy Cox Bellcore
Fred Baker Advanced Computer Communications
James Watt Newbridge
Bill Versteeg Versteeg Codeworks
Steve Buchko Newbridge

Trunk MIB Working Group [Page 47]

RFC 1406 DS1/E1 MIB January 1993

Greg Celmainis Newbridge
Kaj Tesink Bellcore
Al Bryenton Bell Northern Research
Tom Easterday CIC
John Labbe Merit Corporation
Chris Sullivan Gandalf Ltd
Grant Hall Gandalf Ltd
Laurence V. Marks, IBM Corp.
Kurt Hall, Clear Communications Corp.
Myron Hattig, ADC Kentrox

Tracy Cox, Bill Versteeg, Myron Hattig, Kurt Hall and Laurence Marks
especially worked to make the document what it is.

6. References

[1] Rose M., and K. McCloghrie, "Structure and Identification of
Management Information for TCP/IP-based internets", STD 16, RFC
1155, Performance Systems International, Hughes LAN Systems, May
1990.

[2] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
STD 16, RFC 1212, Performance Systems International, Hughes LAN
Systems, March 1991.

[3] 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.

[4] McCloghrie K., and M. Rose, Editors, "Management Information Base
for Network Management of TCP/IP-based internets", STD 17, RFC
1213, Performance Systems International, March 1991.

[5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
Network Management Protocol", STD 15, RFC 1157, SNMP Research,
Performance Systems International, Performance Systems
International, MIT Laboratory for Computer Science, May 1990.

[6] Information processing systems - Open Systems Interconnection -
Specification of Abstract Syntax Notation One (ASN.1),
International Organization for Standardization, International
Standard 8824, December 1987.

[7] 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.

Trunk MIB Working Group [Page 48]

RFC 1406 DS1/E1 MIB January 1993

[8] AT&T Information Systems, AT&T ESF DS1 Channel Service Unit
User's Manual, 999-100-305, February 1988.

[9] AT&T Technical Reference, Requirements for Interfacing Digital
Terminal Equipment to Services Employing the Extended Superframe
Format, Publication 54016, May 1988.

[10] American National Standard for Telecommunications -- Carrier-to-
Customer Installation - DS1 Metallic Interface, T1.403, February
1989.

[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] American National Standard for Telecommunications -- Layer 1 In-
Service Digital Transmission Performance Monitoring T1M1/92-0xx,
T1M1.3/92-005R1, April 1992.

[14] CCITT Specifications Volume IV, Recommendation O.162, Equipment
To Perform In Service Monitoring On 2048 kbit/s Signals, July
1988

[15] CCITT Specifications Volume III, Recommendation G.821, Error
Performance Of An International Digital Connection Forming Part
Of An Integrated Services Digital Network, July 1988.

[16] AT&T Technical Reference, Technical Reference 62411, ACCUNET T1.5
Service Description And Interface Specification, December 1990.

[17] CCITT Specifications Volume III, Recommendation G.706, Frame
Alignment and Cyclic Redundancy Check (CRC) Procedures Relating
to Basic Frame Structures Defined in Recommendation G.704, July
1988.

[18] CCITT Specifications Volume III, Recommendation G.732,
Characteristics Of Primary PCM Multiplex Equipment Operating at
2048 kbit/s, July 1988.

Trunk MIB Working Group [Page 49]

RFC 1406 DS1/E1 MIB January 1993

Security Considerations

Security issues are not discussed in this memo.

Authors' Addresses

Fred Baker
Advanced Computer Communications
315 Bollay Drive
Santa Barbara, California 93117

Phone: (805) 685-4455
EMail: [email protected]

James Watt
Newbridge Networks Corporation
600 March Road
Kanata, Ontario
Canada K2K 2E6

Phone: (613) 591-3600
EMail: [email protected]

Trunk MIB Working Group [Page 50]