|
Network Working Group Request for Comments: 3895 Obsoletes: 2495 Category: Standards Track |
O. Nicklass, Ed. RAD Data Communications, Ltd. September 2004 |
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright © The Internet Society (2004).
This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes objects used for managing DS1, E1, DS2 and E2 interfaces. This document is a companion to the documents that define Managed Objects for the DS0, DS3/E3 and Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) Interface Types. This document obsoletes RFC 2495.
1. The Internet-Standard Management Framework
1.1. Changes from RFC 2495
1.2. Changes from RFC 1406
1.3. Companion Documents
2. Overview
2.1. Use of ifTable for DS1 Layer
2.2. Usage Guidelines
2.2.1. Usage of ifStackTable for Routers and DSUs
2.2.2. Usage of ifStackTable for DS1/E1 on DS2/E2
2.2.3. Usage of Channelization for DS3, DS1, DS0
2.2.4. Usage of Channelization for DS3, DS2, DS1
2.2.5. Usage of Loopbacks
2.3. Objectives of this MIB Module
2.4. DS1 Terminology
2.4.1. Error Events
2.4.2. Performance Defects
2.4.3. Performance Parameters
2.4.4. Failure States
2.4.5. Other Terms
3. Object Definitions
4. Acknowledgments
5. Security Considerations
6. References
6.1. Normative References
6.2. Informative References
Appendix A - Use of dsx1IfIndex and dsx1LineIndex
Appendix B - The delay approach to Unavailable Seconds
Author's Address
Full Copyright Statement
For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP). Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580].
The changes from [RFC2495] are the following:
(1) The dsx1FracIfIndex SYNTAX matches the description range.
(2) A value was added to dsx1TransmitClockSource.
(3) Values were added to dsx1LineType.
(4) Two objects were added, dsx1LineMode and dsx1LineBuildOut to better express transceiver mode and LineBuildOut for T1.
(5) Reference was added to Circuit Identifier object.
(6) Align the DESCRIPTION clauses of few statistic objects with the near end definition, the far end definition and with [RFC3593].
(7) Changes in Compliance Statements to include new objects.
(8) A typographical error in dsx2E2 was fixed, new name is dsx1E2.
The changes from RFC 1406 [RFC1406] are the following:
(1) The Fractional Table has been deprecated.
(2) This document uses SMIv2.
(3) Usage is given for ifTable and ifXTable.
(4) Example usage of ifStackTable is included.
(5) dsx1IfIndex has been deprecated.
(6) Support for DS2 and E2 have been added.
(7) Additional lineTypes for DS2, E2, and unframed E1 were added.
(8) The definition of valid intervals has been clarified for the case where the agent proxied for other devices. In particular, the treatment of missing intervals has been clarified.
(9) An inward loopback has been added.
(10) Additional lineStatus bits have been added for Near End in Unavailable Signal State, Carrier Equipment Out of Service, DS2 Payload AIS, and DS2 Performance Threshold.
(11) A read-write line Length object has been added.
(12) Signal mode of other has been added.
(13) Added a lineStatus last change, trap and enabler.
(14) The e1(19) ifType has been obsoleted so this MIB does not list it as a supported ifType.
(15) Textual Conventions for statistics objects have been used.
(16) A new object, dsx1LoopbackStatus has been introduced to reflect the loopbacks established on a DS1 interface and the source to the requests. dsx1LoopbackConfig continues to be the desired loopback state while dsx1LoopbackStatus reflects the actual state.
(17) A dual loopback has been added to allow the setting of an inward loopback and a line loopback at the same time.
(18) An object indicating which channel to use within a parent object (i.e., DS3) has been added.
(19) An object has been added to indicate whether or not this DS1/E1 is channelized.
(20) Line coding type of B6ZS has been added for DS2.
This document is a companion to the documents that define Managed Objects for the DS0 [RFC2494], DS3/E3 [RFC3896], and Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) [RFC3592] Interface Types.
These objects are used when the particular media being used to realize an interface is a DS1/E1/DS2/E2 interface. At present, this applies to these values of the ifType variable in the Internet- standard MIB:
ds1 (18)
The definitions contained herein are based on the AT&T T-1 Superframe (a.k.a., D4) [ANSI-T1.107] and Extended Superframe (ESF) formats [AT&T-UM-305] [AT&T-TR-54016], the latter of which conforms to ANSI specification [ANSI-T1.403], and the CCITT Recommendations [CCITT-G.703] [ITU-T-G.704], referred to as E1 for the rest of this memo.
The various DS1 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. Therefore, interface types e1(19) and g703at2mb(67) have been obsoleted.
Where it is necessary to distinguish between the flavors of E1 with and without CRC, E1-CRC denotes the "with CRC" form (G.704 Table 4b) and E1-noCRC denotes the "without CRC" form (G.704 Table 4a).
Only the ifGeneralInformationGroup needs to be supported.
ifTable Object Use for DS1 Layer
======================================================================
ifIndex Interface index.
ifDescr See interfaces MIB [RFC2863]
ifType ds1(18)
ifSpeed Speed of line rate
DS1 - 1544000
E1 - 2048000
DS2 - 6312000
E2 - 8448000
ifPhysAddress The value of the Circuit Identifier.
If no Circuit Identifier has been assigned
this object should have an octet string
with zero length.
ifAdminStatus See interfaces MIB [RFC2863]
ifOperStatus See interfaces MIB [RFC2863]
ifLastChange See interfaces MIB [RFC2863]
ifName See interfaces MIB [RFC2863].
ifLinkUpDownTrapEnable Set to enabled(1).
ifHighSpeed Speed of line in Mega-bits per second
(2, 6, or 8)
ifConnectorPresent Set to true(1) normally, except for cases such as DS1/E1 over AAL1/ATM where false(2) is appropriate
The object dsx1IfIndex has been deprecated. This object previously allowed a very special proxy situation to exist for Routers and CSUs. This section now describes how to use ifStackTable to represent this relationship.
The paragraphs discussing dsx1IfIndex and dsx1LineIndex have been preserved in Appendix A for informational purposes.
The ifStackTable is used in the proxy case to represent the association between pairs of interfaces, e.g., this T1 is attached to that T1. This use is consistent with the use of the ifStackTable to show the association between various sub-layers of an interface. In both cases entire PDUs are exchanged between the interface pairs - in the case of a T1, entire T1 frames are exchanged; in the case of PPP and HDLC, entire HDLC frames are exchanged. This usage is not meant to suggest the use of the ifStackTable to represent Time Division Multiplexing (TDM) connections in general.
External&Internal interface scenario: the SNMP Agent resides on a host external from the device supporting DS1 interfaces (e.g., a router). The Agent represents both the host and the DS1 device.
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:
+-----+
| | |
| | | +---------------------+
|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 Description
1 Ethernet
2 Line#A Router
3 Line#B Router
4 Line#C Router
5 Line#D Router
6 Line#A CSU Router
7 Line#B CSU Router
8 Line#C CSU Router
9 Line#D CSU Router
10 Line#A CSU Network
11 Line#B CSU Network
12 Line#C CSU Network
13 Line#D CSU Network
The ifStackTable is then used to show the relationships between the various DS1 interfaces.
ifStackTable Entries
HigherLayer LowerLayer
2 6
3 7
4 8
5 9
6 10
7 11
8 12
9 13
If the CSU shelf is managed by itself by a local SNMP Agent, the situation would be identical, except the Ethernet and the 4 router interfaces are deleted. Interfaces would also be numbered from 1 to 8.
ifIndex Description
1 Line#A CSU Router
2 Line#B CSU Router
3 Line#C CSU Router
4 Line#D CSU Router
5 Line#A CSU Network
6 Line#B CSU Network
7 Line#C CSU Network
8 Line#D CSU Network
ifStackTable Entries
HigherLayer LowerLayer
1 5
2 6
3 7
4 8
An example is given of how DS1/E1 interfaces are stacked on DS2/E2 interfaces. It is not necessary nor is it always desirable to represent DS2 interfaces. If this is required, the following stacking should be used. All ifTypes are ds1. The DS2 is determined by examining ifSpeed or dsx1LineType.
ifIndex Description
1 DS1 #1
2 DS1 #2
3 DS1 #3
4 DS1 #4
5 DS2
ifStackTable Entries
HigherLayer LowerLayer
1 5
2 5
3 5
4 5
An example is given here to explain the channelization objects in the DS3, DS1, and DS0 MIBs to help the implementor use the objects correctly. Treatment of E3 and E1 would be similar, with the number of DS0s being different depending on the framing of the E1.
Assume that a DS3 (with ifIndex 1) is Channelized into DS1s (without DS2s). The object dsx3Channelization is set to enabledDs1. There will be 28 DS1s in the ifTable. Assume the entries in the ifTable for the DS1s are created in channel order and the ifIndex values are 2 through 29. In the DS1 MIB, there will be an entry in the dsx1ChanMappingTable for each ds1. The entries will be as follows:
dsx1ChanMappingTable Entries
ifIndex dsx1Ds1ChannelNumber dsx1ChanMappedIfIndex
1 1 2
1 2 3
1 28 29
In addition, the DS1s are channelized into DS0s. The object
dsx1Channelization is set to enabledDS0 for each DS1. When this
object is set to this value, 24 DS0s are created by the agent. There
will be 24 DS0s in the ifTable for each DS1. If the
dsx1Channelization is set to disabled, the 24 DS0s are destroyed.
Assume the entries in the ifTable are created in channel order and
the ifIndex values for the DS0s in the first DS1 are 30 through 53.
In the DS0 MIB, there will be an entry in the dsx0ChanMappingTable
for each DS0. The entries will be as follows:
dsx0ChanMappingTable Entries
ifIndex dsx0Ds0ChannelNumber dsx0ChanMappedIfIndex
2 1 30
2 2 31
2 24 53
An example is given here to explain the channelization objects in the DS3 and DS1 MIBs to help the implementor use the objects correctly.
Assume that a DS3 (with ifIndex 1) is Channelized into DS2s. The object dsx3Channelization [RFC3896] is set to enabledDs2. There will be 7 DS2s (ifType of DS1) in the ifTable. Assume the entries in the ifTable for the DS2s are created in channel order and the ifIndex values are 2 through 8. In the DS1 MIB, there will be an entry in the dsx1ChanMappingTable for each DS2. The entries will be as follows:
dsx1ChanMappingTable Entries
ifIndex dsx1Ds1ChannelNumber dsx1ChanMappedIfIndex
1 1 2
1 2 3
1 7 8
In addition, the DS2s are channelized into DS1s. The object dsx1Channelization is set to enabledDS1 for each DS2. There will be 4 DS1s in the ifTable for each DS2. Assume the entries in the ifTable are created in channel order and the ifIndex values for the DS1s in the first DS2 are 9 through 12, then 13 through 16 for the second DS2, and so on. In the DS1 MIB, there will be an entry in the dsx1ChanMappingTable for each DS1. The entries will be as follows:
dsx1ChanMappingTable Entries
ifIndex dsx1Ds1ChannelNumber dsx1ChanMappedIfIndex
2 1 9
2 2 10
2 3 11
2 4 12
3 1 13
3 2 14
...
8 4 36
This section discusses the behaviour of objects related to loopbacks.
The object dsx1LoopbackConfig represents the desired state of loopbacks on this interface. Using this object a Manager can request:
LineLoopback
PayloadLoopback (if ESF framing)
InwardLoopback
DualLoopback (Line + Inward)
NoLoopback
The remote end can also request loopbacks either through the FDL channel if ESF or inband if D4. The loopbacks that can be requested this way are:
LineLoopback
PayloadLoopback (if ESF framing)
NoLoopback
To model the current state of loopbacks on a DS1 interface, the object dsx1LoopbackStatus defines which loopback is currently applied to an interface. This objects, which is a bitmap, will have bits turned on which reflect the currently active loopbacks on the interface as well as the source of those loopbacks.
The following restrictions/rules apply to loopbacks:
The far end cannot undo loopbacks set by a manager.
A manager can undo loopbacks set by the far end.
Both a line loopback and an inward loopback can be set at the same time. Only these two loopbacks can co-exist and either one may be set by the manager or the far end. A LineLoopback request from the far end is incremental to an existing Inward loopback established by a manager. When a NoLoopback is received from the far end in this case, the InwardLoopback remains in place.
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, E1, DS2, or E3 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 these types devices that are currently deployed.
J2 interfaces are not supported by this MIB.
The terminology used in this document to describe error conditions on a DS1 interface as monitored by a DS1 device are based on the late but not final document of what became the ANSI T1.231 standard [ANSI-T1.231]. If the definition in this document does not match the definition in the ANSI T1.231 document, the implementer should follow the definition described in this document.
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 (See T1.231
Section 6.1.1.1.1). 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 (See T1.231
Section 6.1.1.1.2). 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.
(Also known as CV-L; See T1.231 Section 6.5.1.1.)
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 or frame
synch. bit error in the ESF and E1-CRC formats. (Also known as
CV-P; See T1.231 Section 6.5.2.1.)
Controlled Slip (CS) Error Event
A Controlled Slip is the replication or deletion of the payload
bits of a DS1 frame (See T1.231 Section 6.1.1.2.3). 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.
Out Of Frame (OOF) Defect
An OOF defect is the occurrence of a particular density of
Framing Error events (See T1.231 Section 6.1.2.2.1).
For DS1 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 [CCITT-G.706]).
For DS2 links, an Out of Frame defect is declared when 7 or more consecutive errored framing patterns (4 multiframe) are received. The OOF is cleared when 3 or more consecutive correct framing patterns are received.
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. (See G.704 Section 4.1)
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 <= 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 T
(See G.775, Section 5.4).
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 [CCITT-O.162] Section 3.3.2).
For DS2 links, the DS2 AIS shall be sent from the NT1 to the user to indicate a loss of the 6,312 kbps frame capability on the network side. The DS2 AIS is defined as a bit array of 6,312 kbps in which all binary bits are set to '1'.
The DS2 AIS detection and removal shall be implemented according to ITU-T Draft Recommendation G.775 [ITU-T-G.775] Section 5.5:
- a DS2 AIS defect is detected when the incoming signal has
two (2) or less ZEROs in a sequence of 3156 bits (0.5 ms).
- a DS2 AIS defect is cleared when the incoming signal has
three (3) or more ZEROs in a sequence of 3156 bits (0.5 ms).
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. Performance parameters continue to be collected when the interface is down.
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.
Performance parameters are of types PerfCurrentCount,
PerfIntervalCount and PerfTotalCount. These textual conventions are
all Gauge32, and they are used because it is possible for these
objects to decrease. Objects may decrease when Unavailable Seconds
occurs across a fifteen minutes interval boundary. See Unavailable
Seconds discussion later in this section.
Line Errored Seconds (LES)
A Line Errored Second is a second in which one or more Line Code
Violation error events were detected. (Also known as ES-L; See
T1.231 Section 6.5.1.2.)
Controlled Slip Seconds (CSS)
A Controlled Slip Second is a one-second interval containing one
or more controlled slips (See T1.231 Section 6.5.2.8). This is
not incremented during an Unavailable Second.
Errored Seconds (ES)
For ESF and E1-CRC links an Errored Second is a second with one
or more Path Code Violation OR one or more Out of Frame defects
OR one or more Controlled Slip events OR a detected AIS defect.
(See T1.231 Section 6.5.2.2 and G.826 [ITU-T-G.826] Section
B.1).
For D4 and E1-noCRC links, the presence of Bipolar 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 in
T1.231 Section 6.5.2.4) 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. It applies to ESF signals only.
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 (See T1.231 Section
6.5.2.5).
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. (Also known as
SAS-P (SEF/AIS second); See T1.231 Section 6.5.2.6.)
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 [CCITT-G.821]).
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 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.
Note that this definition implies that the agent cannot
determine until after a ten second interval has passed whether a
given one-second interval belongs to available or unavailable
time. If the agent chooses to update the various performance
statistics in real time then it must be prepared to
retroactively reduce the ES, BES, SES, and SEFS counts by 10 and
increase the UAS count by 10 when it determines that available
time has been entered. It must also be prepared to adjust the
PCV count and the DM count as necessary since these parameters
are not accumulated during unavailable time. It must be
similarly prepared to retroactively decrease the UAS count by 10
and increase the ES, BES, and DM counts as necessary upon
entering available time. A special case exists when the 10
second period leading to available or unavailable time crosses a
900 second statistics window boundary, as the foregoing description implies that the ES, BES, SES, SEFS, DM, and UAS counts the PREVIOUS interval must be adjusted. In this case 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.
The agent may instead choose to delay updates to the various statistics by 10 seconds in order to avoid retroactive adjustments to the counters. A way to do this is sketched in Appendix B.
In any case, a linkDown trap shall be sent only after the agent has determined for certain that the unavailable state has been entered, but the time on the trap will be that of the first UAS (i.e., 10 seconds earlier). A linkUp trap shall be handled similarly.
According to ANSI T1.231 unavailable time begins at the _onset_ of 10 contiguous severely errored seconds -- that is, unavailable time starts with the _first_ of the 10 contiguous SESs. Also, while an interface is deemed unavailable all counters for that interface are frozen except for the UAS count. It follows that an implementation which strictly complies with this standard must _not_ increment any counters other than the UAS count -- even temporarily -- as a result of anything that happens during those 10 seconds. Since changes in the signal state lag the data to which they apply by 10 seconds, an ANSI-compliant implementation must pass the one-second statistics through a 10-second delay line prior to updating any counters. That can be done by performing the following steps at the end of each one second interval.
i) Read near/far end CV counter and alarm status flags from the
hardware.
ii) Accumulate the CV counts for the preceding second and compare them to the ES and SES threshold for the layer in question. Update the signal state and shift the one-second CV counts and ES/SES flags into the 10-element delay line. Note that far-end one-second statistics are to be flagged as "absent" during any second in which there is an incoming defect at the layer in question or at any lower layer.
iii) Update the current interval statistics using the signal state from the _previous_ update cycle and the one-second CV counts and ES/SES flags shifted out of the 10-element delay line.
This approach is further described in Appendix B.
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.
Far End Alarm Failure
The Far End Alarm failure is also known as "Yellow Alarm" in the
DS1 case, "Distant Alarm" in the E1 case, and "Remote Alarm" in
the DS2 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.
For DS2 links, if a loss of frame alignment (LOF or LOS) and/or DS2 AIS condition, is detected, the RAI signal shall be generated and transmitted to the remote side.
The Remote Alarm Indication(RAI) signal is defined on m-bits as a repetition of the 16bit sequence consisting of eight binary '1s' and eight binary '0s' in m-bits(1111111100000000). When the RAI signal is not sent (in normal operation),the HDLC flag pattern (01111110) in the m-bit is sent.
The RAI failure is detected when 16 or more consecutive RAI- patterns (1111111100000000) are received. The RAI failure is cleared when 4 or more consecutive incorrect-RAI-patterns are received.
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. (See T1.231 Section 6.2.1.2.1)
An AIS defect at a 6312 kbit/s (G.704) interface is detected when the incoming signal has two {2} or less ZEROs in a sequence of 3156 bits (0.5ms). The AIS signal defect is cleared when the incoming signal has three {3} or more ZEROs in a sequence of 3156 bits (0.5ms).
Loss Of Frame Failure
For DS1 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
[AT&T-TR-62411].
For E1 links, the Loss Of Frame Failure is declared when an OOF defect is detected.
Loss Of Signal Failure
For DS1, 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 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).
A LOS defect at 6312kbit/s interfaces is detected when the incoming signal has "no transitions", i.e., when the signal level is less than or equal to a signal level of 35dB below nominal, for N consecutive pulse intervals, where 10 <=N<=255.
The LOS defect is cleared when the incoming signal has "transitions", i.e., when the signal level is greater than or equal to a signal level of 9dB below nominal, for N consecutive pulse intervals, where 10<=N<=255.
A signal with "transitions" corresponds to a G.703 compliant signal.
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 DS1.
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 [CCITT-G.732] 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 (See G.732).
DS2 Payload AIS Failure
The DS2 Payload AIS is detected when the incoming signal of the
6,312 kbps frame payload (time-slots 1 through 96) has 2 or less
0's in a sequence of 3072 bits (0.5ms). The DS2 Payload AIS is
cleared when the incoming signal of the 6,312 kbps frame payload
has 3 or more 0's in a sequence of 3072 bits (0.5 ms).
DS2 Performance Threshold
DS2 Performance Threshold Failure monitors equipment performance
and is based on the CRC (Cyclic Redundancy Check) Procedure
defined in G.704.
The DS2 Performance Threshold Failure is detected when the bit error ratio exceeds 10^-4 (Performance Threshold), and the DS2 Performance Threshold Failure shall be cleared when the bit error ratio decreased to less than 10^-6."
Circuit Identifier
This is a character string specified by the circuit vendor, and is
useful when communicating with the vendor during the
troubleshooting process (see M.1400 [ITU-T-M.1400] for additional
information).
Proxy
In this document, the word proxy is meant to indicate an
application which receives SNMP messages and replies to them on
behalf of the devices which implement the actual DS1/E1
interfaces. The proxy may have already collected the information
about the DS1/E1 interfaces into its local database and may not
necessarily forward the requests to the actual DS1/E1 interface.
It is expected in such an application that there are periods of
time where the proxy is not communicating with the DS1/E1
interfaces. In these instances the proxy will not necessarily
have up-to-date configuration information and will most likely
have missed the collection of some statistics data. Missed
statistics data collection will result in invalid data in the
interval table.
DS1-MIB DEFINITIONS ::= BEGIN
FROM SNMPv2-SMI -- [RFC2578]
DisplayString, TimeStamp, TruthValue
FROM SNMPv2-TC -- [RFC2579]
MODULE-COMPLIANCE, OBJECT-GROUP,
NOTIFICATION-GROUP
FROM SNMPv2-CONF -- [RFC2580]
InterfaceIndex, ifIndex
FROM IF-MIB -- [RFC2863]
PerfCurrentCount, PerfIntervalCount,
PerfTotalCount
FROM PerfHist-TC-MIB; -- [RFC3593]
Mailing Lists:
General Discussion: atommib@research.telcordia.com
To Subscribe: atommib-request@research.telcordia.com
Editor: Orly Nicklass
Postal: RAD Data Communications, Ltd.
Ziv Tower, 24 Roul Walenberg
Tel Aviv, Israel, 69719
Tel: +9723 765 9969
E-mail: orly_n@rad.com"
DESCRIPTION
"The MIB module to describe DS1, E1, DS2, and
E2 interfaces objects.
Copyright (c) The Internet Society (2004). This
version of this MIB module is part of RFC 3895;
see the RFC itself for full legal notices."
REVISION "200409090000Z" -- September 09, 2004
DESCRIPTION
"The RFC 3895 version of this MIB module.
The key changes made to this MIB module
since its publication in RFC 2495 are as follows:
(1) The dsx1FracIfIndex SYNTAX matches the description range.
(2) A value was added to dsx1TransmitClockSource.
(3) Values were added to dsx1LineType.
(4) Two objects were added, dsx1LineMode and dsx1LineBuildOut
to better express transceiver mode and LineBuildOut for T1.
(5) Reference was added to Circuit Identifier object.
(6) Align the DESCRIPTION clauses of few statistic objects with
the near end definition, the far end definition and with
RFC 3593.
(7) Changes in Compliance Statements to include new objects.
(8) A typographical error in dsx2E2 was fixed, new name is dsx1E2."
REVISION "199808011830Z"
DESCRIPTION
"The RFC 2495 version of this MIB module.
The key changes made to this MIB module
since its publication in RFC 1406 are as follows:
(1) The Fractional Table has been deprecated.
(2) This document uses SMIv2.
(3) Usage is given for ifTable and ifXTable.
(4) Example usage of ifStackTable is included.
(5) dsx1IfIndex has been deprecated.
(6) Support for DS2 and E2 have been added.
(7) Additional lineTypes for DS2, E2, and unframed E1
were added.
(8) The definition of valid intervals has been clarified
for the case where the agent proxied for other devices. In
particular, the treatment of missing intervals has been
clarified.
(9) An inward loopback has been added.
(10) Additional lineStatus bits have been added for Near End in
Unavailable Signal State, Carrier Equipment Out of Service,
DS2 Payload AIS, and DS2 Performance Threshold.
(11) A read-write line Length object has been added.
(12) Signal mode of other has been added.
(13) Added a lineStatus last change, trap and enabler.
(14) The e1(19) ifType has been obsoleted so this MIB
does not list it as a supported ifType.
(15) Textual Conventions for statistics objects have been used.
(16) A new object, dsx1LoopbackStatus has been introduced to
reflect the loopbacks established on a DS1 interface and
the source to the requests. dsx1LoopbackConfig continues
to be the desired loopback state while dsx1LoopbackStatus
reflects the actual state.
(17) A dual loopback has been added to allow the setting of an
inward loopback and a line loopback at the same time.
(18) An object indicating which channel to use within a parent
object (i.e., DS3) has been added.
(19) An object has been added to indicate whether or not this
DS1/E1 is channelized.
(20) Line coding type of B6ZS has been added for DS2"
REVISION "199301252028Z"
DESCRIPTION
"Initial version, published as RFC 1406."
::= { transmission 18 }
-- note that this subsumes cept (19) and g703at2mb (67)
-- there is no separate CEPT or G703AT2MB MIB -- The DS1 Near End Group -- The DS1 Near End Group consists of five tables:
-- DS1 Configuration
-- DS1 Current
-- DS1 Interval
-- DS1 Total
-- DS1 Channel Table
-- The DS1 Configuration Table
::= { ds1 6 }
INDEX { dsx1LineIndex }
::= { dsx1ConfigTable 1 }
Dsx1ConfigEntry ::=
SEQUENCE {
dsx1LineIndex InterfaceIndex,
dsx1IfIndex InterfaceIndex,
dsx1TimeElapsed INTEGER,
dsx1ValidIntervals INTEGER,
dsx1LineType INTEGER,
dsx1LineCoding INTEGER,
dsx1SendCode INTEGER,
dsx1CircuitIdentifier DisplayString,
dsx1LoopbackConfig INTEGER,
dsx1LineStatus INTEGER,
dsx1SignalMode INTEGER,
dsx1TransmitClockSource INTEGER,
dsx1Fdl INTEGER,
dsx1InvalidIntervals INTEGER,
dsx1LineLength INTEGER,
dsx1LineStatusLastChange TimeStamp,
dsx1LineStatusChangeTrapEnable INTEGER,
dsx1LoopbackStatus INTEGER,
dsx1Ds1ChannelNumber INTEGER,
dsx1Channelization INTEGER,
dsx1LineMode INTEGER,
dsx1LineBuildOut INTEGER
}
-- SMIv1 index
STATUS current
DESCRIPTION
"This object should be made equal to ifIndex. The
next paragraph describes its previous usage.
Making the object equal to ifIndex allows proper
use of ifStackTable and ds0/ds0bundle mibs.
Previously, this object is the identifier of 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 that is
greater than ifNumber and numbering the inside
interfaces (e.g., equipment side) with even
numbers and outside interfaces (e.g., network side)
with odd numbers."
::= { dsx1ConfigEntry 1 }
::= { dsx1ConfigEntry 2 }
::= { dsx1ConfigEntry 3 }
DESCRIPTION
"The number of previous near end intervals for
which 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 near end intervals
since the interface has been online. In the case
where the agent is a proxy, it is possible that
some intervals are unavailable. In this case,
this interval is the maximum interval number for
which data is available."
::= { dsx1ConfigEntry 4 }
SYNTAX INTEGER {
other(1),
dsx1ESF(2),
dsx1D4(3),
dsx1E1(4),
dsx1E1CRC(5),
dsx1E1MF(6),
dsx1E1CRCMF(7),
dsx1Unframed(8),
dsx1E1Unframed(9),
dsx1DS2M12(10),
dsx1E2(11),
dsx1E1Q50(12),
dsx1E1Q50CRC(13)
}
MAX-ACCESS read-write
STATUS current
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
(T1.107)
dsx1D4 AT&T D4 format DS1 (T1.107)
dsx1E1 ITU-T Recommendation G.704
(Table 4a)
dsx1E1-CRC ITU-T 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
dsx1Unframed DS1 with No Framing
dsx1E1Unframed E1 with No Framing (G.703)
dsx1DS2M12 DS2 frame format (T1.107)
dsx1E2 E2 frame format (G.704)
dsx1E1Q50 TS16 bits 5,7,8 set to 101, [in
all other cases it is set
to 111.](ITU-T G.704,table 14)
dsx1E1Q50CRC E1Q50 with CRC.
For clarification, the capacity for each E1 type is as listed below:
dsx1E1Unframed - E1, no framing = 32 x 64k = 2048k
dsx1E1 or dsx1E1CRC - E1, with framing,
no signalling = 31 x 64k = 1984k
dsx1E1MF or dsx1E1CRCMF - E1, with framing,
signalling = 30 x 64k = 1920k"
REFERENCE
"American National Standard for telecommunications -
digital hierarchy - formats specification,
ANSI-T1.107 - 1988.
CCITT Specifications Volume III, Recommendation
G.703, Physical/Electrical Characteristics
of Hierarchical Digital Interfaces, April 1991.
ITU-T-G.704: Synchronous frame structures used at
1544, 6312, 2048, 8488 and 44 736 kbit/s
Hierarchical Levels, July 1995."
::= { dsx1ConfigEntry 5 }
SYNTAX INTEGER {
dsx1JBZS (1),
dsx1B8ZS (2),
dsx1HDB3 (3),
dsx1ZBTSI (4),
dsx1AMI (5),
other(6),
dsx1B6ZS(7)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This variable describes the variety of Zero Code
Suppression used on this interface, which in turn
affects a number of its characteristics.
dsx1JBZS refers the Jammed Bit Zero Suppression,
in which the AT&T specification of at least one
pulse every 8 bit periods is literally implemented
by forcing a pulse in bit 8 of each channel.
Thus, only seven bits per channel, or 1.344 Mbps,
is available for data.
dsx1B8ZS 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.
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
requirements, such as inverting HDLC data.
dsx1B6ZS refers to the user of a specified pattern
of normal bits and bipolar violations which are
used to replace a sequence of six zero bits. Used
for DS2."
::= { dsx1ConfigEntry 6 }
SYNTAX INTEGER {
dsx1SendNoCode(1),
dsx1SendLineCode(2),
dsx1SendPayloadCode(3),
dsx1SendResetCode(4),
dsx1SendQRS(5),
dsx1Send511Pattern(6),
dsx1Send3in24Pattern(7),
dsx1SendOtherTestPattern(8)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This variable indicates what type of code is
being sent across the DS1 interface by the device.
Setting this variable causes the interface to send
the code requested. 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
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 }
::= { dsx1ConfigEntry 8 }
SYNTAX INTEGER {
dsx1NoLoop(1),
dsx1PayloadLoop(2),
dsx1LineLoop(3),
dsx1OtherLoop(4),
dsx1InwardLoop(5),
dsx1DualLoop(6)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This variable represents the desired loopback
configuration of the DS1 interface. Agents
supporting read/write access should return
inconsistentValue in response to a requested
loopback state that the interface does not
support. The values mean:
dsx1NoLoop
Not in the loopback state. A device that is not
capable of performing a loopback on the interface
shall always return this as its value.
dsx1PayloadLoop
The received signal at this interface is looped
through the device. Typically the received signal
is looped back for retransmission after it has
passed through the device's framing function.
dsx1LineLoop
The received signal at this interface does not go
through the device (minimum penetration) but is
looped back out.
dsx1OtherLoop
Loopbacks that are not defined here.
dsx1InwardLoop
The transmitted signal at this interface is
looped back and received by the same interface.
What is transmitted onto the line is product
dependent.
dsx1DualLoop
Both dsx1LineLoop and dsx1InwardLoop will be
active simultaneously."
::= { dsx1ConfigEntry 9 }
information.
The dsx1LineStatus is a bit map represented as a sum, therefore, it can represent multiple failures (alarms) and a LoopbackState simultaneously.
dsx1NoAlarm must be set if and only if no other
flag is set.
If the dsx1loopbackState bit is set, the loopback
in effect 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
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
8192 dsx1UnavailSigState Near End in Unavailable Signal
State
16384 dsx1NetEquipOOS Carrier Equipment Out of Service
32768 dsx1RcvPayloadAIS DS2 Payload AIS
65536 dsx1Ds2PerfThreshold DS2 Performance Threshold
Exceeded"
::= { dsx1ConfigEntry 10 }
SYNTAX INTEGER {
none (1),
robbedBit (2),
bitOriented (3),
messageOriented (4),
other (5)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"'none' indicates that no bits are reserved for
signaling on this channel.
'robbedBit' indicates that DS1 Robbed Bit Signaling
is in use.
'bitOriented' indicates that E1 Channel
Associated Signaling is in use.
'messageOriented' indicates that Common
Channel Signaling is in use either on channel 16
of an E1 link or channel 24 of a DS1."
::= { dsx1ConfigEntry 11 }
SYNTAX INTEGER {
loopTiming(1),
localTiming(2),
throughTiming(3),
adaptive (4)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"The source of Transmit Clock.
'loopTiming' indicates that the recovered
receive clock is used as the transmit clock.
'localTiming' indicates that a local clock
source is used or when an external clock is
attached to the box containing the interface.
'throughTiming' indicates that recovered
receive clock from another interface is used as
the transmit clock.
'adaptive' indicates that the clock is recovered
based on the data flow and not based on the
physical layer"
::= { dsx1ConfigEntry 12 }
other(1),
dsx1AnsiT1403(2),
dsx1Att54016(4),
dsx1FdlNone(8)
'other' indicates that a protocol other than
one following is used.
'dsx1AnsiT1403' refers to the FDL exchange
recommended by ANSI.
'dsx1Att54016' refers to ESF FDL exchanges.
'dsx1FdlNone' indicates that the device does
not use the FDL."
::= { dsx1ConfigEntry 13 }
::= { dsx1ConfigEntry 14 }
::= { dsx1ConfigEntry 15 }
state. If the current state was entered prior to
the last re-initialization of the proxy-agent,
then this object contains a zero value."
::= { dsx1ConfigEntry 16 }
SYNTAX INTEGER {
enabled(1),
disabled(2)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Indicates whether dsx1LineStatusChange traps
should be generated for this interface."
DEFVAL { disabled }
::= { dsx1ConfigEntry 17 }
SYNTAX INTEGER (1..127)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This variable represents the current state of the
loopback on the DS1 interface. It contains
information about loopbacks established by a
manager and remotely from the far end.
The dsx1LoopbackStatus is a bit map represented as
a sum, therefore is can represent multiple
loopbacks simultaneously.
The various bit positions are:
1 dsx1NoLoopback
2 dsx1NearEndPayloadLoopback
4 dsx1NearEndLineLoopback
8 dsx1NearEndOtherLoopback
16 dsx1NearEndInwardLoopback
32 dsx1FarEndPayloadLoopback
64 dsx1FarEndLineLoopback"
::= { dsx1ConfigEntry 18 }
SYNTAX INTEGER (0..28)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This variable represents the channel number of
the DS1/E1 on its parent DS2/E2 or DS3/E3. A
value of 0 indicated this DS1/E1 does not have a
parent DS3/E3."
::= { dsx1ConfigEntry 19 }
SYNTAX INTEGER {
disabled(1),
enabledDs0(2),
enabledDs1(3)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Indicates whether this ds1/e1 is channelized or
unchannelized. The value of enabledDs0 indicates
that this is a DS1 channelized into DS0s. The
value of enabledDs1 indicated that this is a DS2
channelized into DS1s. Setting this value will
cause the creation or deletion of entries in the
ifTable for the DS0s that are within the DS1."
::= { dsx1ConfigEntry 20 }
SYNTAX INTEGER {
csu(1),
dsu(2)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This setting puts the T1 framer into either long
haul (CSU) mode or short haul (DSU) mode."
::= { dsx1ConfigEntry 21 }
SYNTAX INTEGER {
notApplicable (1),
neg75dB (2),
neg15dB (3),
neg225dB (4),
zerodB (5)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Attenuation setting for T1 framer in long haul
(CSU) mode. The optional values are: -7.5dB,
-15dB, -22.5dB and 0dB."
::= { dsx1ConfigEntry 22 }
-- The DS1 Current Table
::= { ds1 7 }
INDEX { dsx1CurrentIndex }
::= { dsx1CurrentTable 1 }
Dsx1CurrentEntry ::=
SEQUENCE {
dsx1CurrentIndex InterfaceIndex,
dsx1CurrentESs PerfCurrentCount,
dsx1CurrentSESs PerfCurrentCount,
dsx1CurrentSEFSs PerfCurrentCount,
dsx1CurrentUASs PerfCurrentCount,
dsx1CurrentCSSs PerfCurrentCount,
dsx1CurrentPCVs PerfCurrentCount,
dsx1CurrentLESs PerfCurrentCount,
dsx1CurrentBESs PerfCurrentCount,
dsx1CurrentDMs PerfCurrentCount,
dsx1CurrentLCVs PerfCurrentCount
}
-- SMIv1 index
STATUS current
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface 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 as a dsx1LineIndex object
instance."
::= { dsx1CurrentEntry 1 }
::= { dsx1CurrentEntry 2 }
::= { dsx1CurrentEntry 3 }
::= { dsx1CurrentEntry 4 }
::= { dsx1CurrentEntry 5 }
::= { dsx1CurrentEntry 6 }
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of Path Coding Violations."
::= { dsx1CurrentEntry 7 }
::= { dsx1CurrentEntry 8 }
::= { dsx1CurrentEntry 9 }
::= { dsx1CurrentEntry 10 }
::= { dsx1CurrentEntry 11 }
-- The DS1 Interval Table
intervals. Each row in this table represents one
such interval (identified by dsx1IntervalNumber)
for one specific instance (identified by
dsx1IntervalIndex)."
::= { ds1 8 }
INDEX { dsx1IntervalIndex, dsx1IntervalNumber }
::= { dsx1IntervalTable 1 }
Dsx1IntervalEntry ::=
SEQUENCE {
dsx1IntervalIndex InterfaceIndex,
dsx1IntervalNumber INTEGER,
dsx1IntervalESs PerfIntervalCount,
dsx1IntervalSESs PerfIntervalCount,
dsx1IntervalSEFSs PerfIntervalCount,
dsx1IntervalUASs PerfIntervalCount,
dsx1IntervalCSSs PerfIntervalCount,
dsx1IntervalPCVs PerfIntervalCount,
dsx1IntervalLESs PerfIntervalCount,
dsx1IntervalBESs PerfIntervalCount,
dsx1IntervalDMs PerfIntervalCount,
dsx1IntervalLCVs PerfIntervalCount,
dsx1IntervalValidData TruthValue
}
-- SMIv1 index
STATUS current
DESCRIPTION
"The index value which uniquely identifies the DS1
interface 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 as a dsx1LineIndex object instance."
::= { dsx1IntervalEntry 1 }
-- SMIv1 index
STATUS current
DESCRIPTION
"A number between 1 and 96, where 1 is the most
recently completed 15 minute interval and 96 is
the 15 minutes interval completed 23 hours and 45
minutes prior to interval 1."
::= { dsx1IntervalEntry 2 }
::= { dsx1IntervalEntry 3 }
::= { dsx1IntervalEntry 4 }
::= { dsx1IntervalEntry 5 }
::= { dsx1IntervalEntry 6 }
"The number of Controlled Slip Seconds."
::= { dsx1IntervalEntry 7 }
::= { dsx1IntervalEntry 8 }
::= { dsx1IntervalEntry 9 }
::= { dsx1IntervalEntry 10 }
::= { dsx1IntervalEntry 11 }
::= { dsx1IntervalEntry 12 }
"This variable indicates if the data for this
interval is valid."
::= { dsx1IntervalEntry 13 }
-- The DS1 Total Table
::= { ds1 9 }
INDEX { dsx1TotalIndex }
::= { dsx1TotalTable 1 }
Dsx1TotalEntry ::=
SEQUENCE {
dsx1TotalIndex InterfaceIndex,
dsx1TotalESs PerfTotalCount,
dsx1TotalSESs PerfTotalCount,
dsx1TotalSEFSs PerfTotalCount,
dsx1TotalUASs PerfTotalCount,
dsx1TotalCSSs PerfTotalCount,
dsx1TotalPCVs PerfTotalCount,
dsx1TotalLESs PerfTotalCount,
dsx1TotalBESs PerfTotalCount,
dsx1TotalDMs PerfTotalCount,
dsx1TotalLCVs PerfTotalCount
}
-- SMIv1 index
STATUS current
DESCRIPTION
"The index value which uniquely identifies the DS1
interface 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 as a dsx1LineIndex object instance."
::= { dsx1TotalEntry 1 }
::= { dsx1TotalEntry 2 }
::= { dsx1TotalEntry 3 }
::= { dsx1TotalEntry 4 }
::= { dsx1TotalEntry 5 }
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of Controlled Slip Seconds encountered
by a DS1 interface in the previous 24 hour
interval. Invalid 15 minute intervals count as
0."
::= { dsx1TotalEntry 6 }
::= { dsx1TotalEntry 7 }
::= { dsx1TotalEntry 8 }
::= { dsx1TotalEntry 9 }
interval. Invalid 15 minute intervals count as
0."
::= { dsx1TotalEntry 10 }
::= { dsx1TotalEntry 11 }
-- The DS1 Channel Table
::= { ds1 16 }
This table is intended to facilitate mapping from
channelized interface / channel number to DS1
ifEntry. (e.g., mapping (DS3 ifIndex, DS1 Channel
Number) -> ifIndex)
While this table provides information that can
also be found in the ifStackTable and
dsx1ConfigTable, it provides this same information
with a single table lookup, rather than by walking
the ifStackTable to find the various constituent
ds1 ifTable entries, and testing various
dsx1ConfigTable entries to check for the entry
with the applicable DS1 channel number."
INDEX { ifIndex, dsx1Ds1ChannelNumber }
::= { dsx1ChanMappingTable 1 }
Dsx1ChanMappingEntry ::=
SEQUENCE {
dsx1ChanMappedIfIndex InterfaceIndex
}
::= { dsx1ChanMappingEntry 1 }
-- The DS1 Far End Current Table
::= { ds1 10 }
INDEX { dsx1FarEndCurrentIndex }
::= { dsx1FarEndCurrentTable 1 }
Dsx1FarEndCurrentEntry ::=
SEQUENCE {
dsx1FarEndCurrentIndex InterfaceIndex,
dsx1FarEndTimeElapsed INTEGER,
dsx1FarEndValidIntervals INTEGER,
dsx1FarEndCurrentESs PerfCurrentCount,
dsx1FarEndCurrentSESs PerfCurrentCount,
dsx1FarEndCurrentSEFSs PerfCurrentCount,
dsx1FarEndCurrentUASs PerfCurrentCount,
dsx1FarEndCurrentCSSs PerfCurrentCount,
dsx1FarEndCurrentLESs PerfCurrentCount,
dsx1FarEndCurrentPCVs PerfCurrentCount,
dsx1FarEndCurrentBESs PerfCurrentCount,
dsx1FarEndCurrentDMs PerfCurrentCount,
dsx1FarEndInvalidIntervals INTEGER
}
-- SMIv1 index
STATUS current
DESCRIPTION
"The index value which uniquely identifies the DS1
interface to which this entry is applicable. The
interface identified by a particular value of this
index is identical to the interface identified by
the same value of dsx1LineIndex."
::= { dsx1FarEndCurrentEntry 1 }
::= { dsx1FarEndCurrentEntry 2 }
"The number of previous far end intervals for
which 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. In the case
where the agent is a proxy, it is possible that
some intervals are unavailable. In this case,
this interval is the maximum interval number for
which data is available."
::= { dsx1FarEndCurrentEntry 3 }
::= { dsx1FarEndCurrentEntry 4 }
::= { dsx1FarEndCurrentEntry 5 }
::= { dsx1FarEndCurrentEntry 6 }
::= { dsx1FarEndCurrentEntry 7 }
STATUS current
DESCRIPTION
"The number of Far End Controlled Slip Seconds."
::= { dsx1FarEndCurrentEntry 8 }
::= { dsx1FarEndCurrentEntry 9 }
::= { dsx1FarEndCurrentEntry 10 }
::= { dsx1FarEndCurrentEntry 11 }
::= { dsx1FarEndCurrentEntry 12 }
::= { dsx1FarEndCurrentEntry 13 }
-- The DS1 Far End Interval Table
::= { ds1 11 }
INDEX { dsx1FarEndIntervalIndex,
dsx1FarEndIntervalNumber }
::= { dsx1FarEndIntervalTable 1 }
Dsx1FarEndIntervalEntry ::=
SEQUENCE {
dsx1FarEndIntervalIndex InterfaceIndex,
dsx1FarEndIntervalNumber INTEGER,
dsx1FarEndIntervalESs PerfIntervalCount,
dsx1FarEndIntervalSESs PerfIntervalCount,
dsx1FarEndIntervalSEFSs PerfIntervalCount,
dsx1FarEndIntervalUASs PerfIntervalCount,
dsx1FarEndIntervalCSSs PerfIntervalCount,
dsx1FarEndIntervalLESs PerfIntervalCount,
dsx1FarEndIntervalPCVs PerfIntervalCount,
dsx1FarEndIntervalBESs PerfIntervalCount,
dsx1FarEndIntervalDMs PerfIntervalCount,
dsx1FarEndIntervalValidData TruthValue
}
-- SMIv1 index
STATUS current
DESCRIPTION
"The index value which uniquely identifies the DS1 interface to which this entry is applicable. The interface identified by a particular value of this index is identical to the interface identified by the same value of dsx1LineIndex."
::= { dsx1FarEndIntervalEntry 1 }
-- SMIv1 index
STATUS current
DESCRIPTION
"A number between 1 and 96, where 1 is the most
recently completed 15 minute interval and 96 is
the 15 minutes interval completed 23 hours and 45
minutes prior to interval 1."
::= { dsx1FarEndIntervalEntry 2 }
::= { dsx1FarEndIntervalEntry 3 }
::= { dsx1FarEndIntervalEntry 4 }
::= { dsx1FarEndIntervalEntry 5 }
DESCRIPTION
"The number of Unavailable Seconds."
::= { dsx1FarEndIntervalEntry 6 }
::= { dsx1FarEndIntervalEntry 7 }
::= { dsx1FarEndIntervalEntry 8 }
::= { dsx1FarEndIntervalEntry 9 }
::= { dsx1FarEndIntervalEntry 10 }
::= { dsx1FarEndIntervalEntry 11 }
DESCRIPTION
" This variable indicates if the data for this
interval is valid."
::= { dsx1FarEndIntervalEntry 12 }
-- The DS1 Far End Total Table
::= { ds1 12 }
INDEX { dsx1FarEndTotalIndex }
::= { dsx1FarEndTotalTable 1 }
Dsx1FarEndTotalEntry ::=
SEQUENCE {
dsx1FarEndTotalIndex InterfaceIndex,
dsx1FarEndTotalESs PerfTotalCount,
dsx1FarEndTotalSESs PerfTotalCount,
dsx1FarEndTotalSEFSs PerfTotalCount,
dsx1FarEndTotalUASs PerfTotalCount,
dsx1FarEndTotalCSSs PerfTotalCount,
dsx1FarEndTotalLESs PerfTotalCount,
dsx1FarEndTotalPCVs PerfTotalCount,
dsx1FarEndTotalBESs PerfTotalCount,
dsx1FarEndTotalDMs PerfTotalCount
}
-- SMIv1 index
STATUS current
DESCRIPTION
"The index value which uniquely identifies the DS1
interface to which this entry is applicable. The
interface identified by a particular value of this index is identical to the interface identified by the same value of dsx1LineIndex."
::= { dsx1FarEndTotalEntry 1 }
::= { dsx1FarEndTotalEntry 2 }
::= { dsx1FarEndTotalEntry 3 }
::= { dsx1FarEndTotalEntry 4 }
::= { dsx1FarEndTotalEntry 5 }
::= { dsx1FarEndTotalEntry 6 }
::= { dsx1FarEndTotalEntry 7 }
::= { dsx1FarEndTotalEntry 8 }
::= { dsx1FarEndTotalEntry 9 }
STATUS current
DESCRIPTION
"The number of Degraded Minutes (DMs) encountered
by a DS1 interface in the previous 24 hour
interval. Invalid 15 minute intervals count as
0."
::= { dsx1FarEndTotalEntry 10 }
-- The DS1 Fractional Table
The table was mandatory for 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 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
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."
::= { ds1 13 }
INDEX { dsx1FracIndex, dsx1FracNumber }
::= { dsx1FracTable 1 }
Dsx1FracEntry ::=
SEQUENCE {
dsx1FracIndex INTEGER,
dsx1FracNumber INTEGER,
dsx1FracIfIndex INTEGER
}
-- SMIv1 index
STATUS deprecated
DESCRIPTION
"The index value which uniquely identifies the
DS1 interface 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 dsx1LineIndex
object instance."
::= { dsx1FracEntry 1 }
-- SMIv1 index
STATUS deprecated
DESCRIPTION
"The channel number for this entry."
::= { dsx1FracEntry 2 }
::= { dsx1FracEntry 3 }
-- DS1 TRAPS
ds1Traps OBJECT IDENTIFIER ::= { ds1 15 }
::= { ds1Traps 0 1 }
-- conformance information
ds1Conformance OBJECT IDENTIFIER ::= { ds1 14 }
ds1Groups OBJECT IDENTIFIER ::= { ds1Conformance 1 }
ds1Compliances OBJECT IDENTIFIER ::= { ds1Conformance 2 }
-- compliance statements
GROUP ds1FarEndGroup
DESCRIPTION
"Implementation of this group is optional for all
systems that attach to a DS1 Interface."
GROUP ds1NearEndOptionalConfigGroup
DESCRIPTION
"Implementation of this group is optional for all
systems that attach to a DS1 Interface."
GROUP ds1DS2Group
DESCRIPTION
"Implementation of this group is mandatory for all
systems that attach to a DS2 Interface."
GROUP ds1TransStatsGroup
DESCRIPTION
"This group is the set of statistics appropriate
for all systems which attach to a DS1 Interface
running transparent or unFramed lineType."
GROUP ds1ChanMappingGroup
DESCRIPTION
"This group is the set of objects for mapping a
DS3 Channel (dsx1Ds1ChannelNumber) to ifIndex.
Implementation of this group is mandatory for
systems which support the channelization of DS3s
into DS1s."
OBJECT dsx1LineType
SYNTAX INTEGER {
other(1),
dsx1ESF(2),
dsx1D4(3),
dsx1E1(4),
dsx1E1CRC(5),
dsx1E1MF(6),
dsx1E1CRCMF(7),
dsx1Unframed(8),
dsx1E1Unframed(9),
dsx1DS2M12(10),
dsx1E2(11)
}
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the line type is not
required."
OBJECT dsx1LineCoding
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the line coding is not
required."
OBJECT dsx1SendCode
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the send code is not
required."
OBJECT dsx1LoopbackConfig
MIN-ACCESS read-only
DESCRIPTION
"The ability to set loopbacks is not required."
OBJECT dsx1SignalMode
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the signal mode is not
required."
OBJECT dsx1TransmitClockSource
SYNTAX INTEGER {
loopTiming(1),
localTiming(2),
throughTiming(3)
}
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the transmit clock source is not required."
OBJECT dsx1Fdl
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the FDL is not required."
OBJECT dsx1LineLength
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the line length is not
required."
OBJECT dsx1Channelization
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the channelization is not
required."
::= { ds1Compliances 1 }
SYNTAX INTEGER {
dsx1ESF(2) -- Intl Spec would be G704(2)
-- or I.431(4)
}
MIN-ACCESS read-only
DESCRIPTION
"Line type for T1 ISDN Primary Rate
interfaces."
OBJECT dsx1LineCoding
SYNTAX INTEGER {
dsx1B8ZS(2)
}
MIN-ACCESS read-only
DESCRIPTION
"Type of Zero Code Suppression for
T1 ISDN Primary Rate interfaces."
OBJECT dsx1SignalMode
SYNTAX INTEGER {
none(1), -- if there is no signaling channel
messageOriented(4)
}
MIN-ACCESS read-only
DESCRIPTION
"Possible signaling modes for
T1 ISDN Primary Rate interfaces."
OBJECT dsx1TransmitClockSource
SYNTAX INTEGER {
loopTiming(1)
}
MIN-ACCESS read-only
DESCRIPTION
"The transmit clock is derived from
received clock on ISDN Primary Rate
interfaces."
OBJECT dsx1Fdl
MIN-ACCESS read-only
DESCRIPTION
"Facilities Data Link usage on T1 ISDN
Primary Rate interfaces.
Note: Eventually dsx1Att-54016(4) is to be
used here since the line type is ESF."
OBJECT dsx1Channelization
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the channelization
is not required."
::= { ds1Compliances 2 }
SYNTAX INTEGER {
dsx1E1CRC(5)
}
MIN-ACCESS read-only
DESCRIPTION
"Line type for E1 ISDN Primary Rate
interfaces."
OBJECT dsx1LineCoding
SYNTAX INTEGER {
dsx1HDB3(3)
}
MIN-ACCESS read-only
DESCRIPTION
"Type of Zero Code Suppression for
E1 ISDN Primary Rate interfaces."
OBJECT dsx1SignalMode
SYNTAX INTEGER {
messageOriented(4)
}
MIN-ACCESS read-only
DESCRIPTION
"Signaling on E1 ISDN Primary Rate interfaces
is always message oriented."
OBJECT dsx1TransmitClockSource
SYNTAX INTEGER {
loopTiming(1)
}
MIN-ACCESS read-only
DESCRIPTION
"The transmit clock is derived from received
clock on ISDN Primary Rate interfaces."
OBJECT dsx1Fdl
MIN-ACCESS read-only
DESCRIPTION
"Facilities Data Link usage on E1 ISDN
Primary Rate interfaces.
Note: There is a 'M-Channel' in E1,
using National Bit Sa4 (G704,
Table 4a). It is used to implement
management features between ET
and NT. This is different to
FDL in T1, which is used to carry
control signals and performance
data. In E1, control and status
signals are carried using National
Bits Sa5, Sa6 and A (RAI Ind.).
This indicates that only the other(1) or
eventually the dsx1Fdl-none(8) bits should
be set in this object for E1 PRI."
OBJECT dsx1Channelization
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the channelization is not
required."
::= { ds1Compliances 3 }
OBJECT dsx1LineType
SYNTAX INTEGER {
dsx1DS2M12(10),
dsx1E2(11)
}
MIN-ACCESS read-only
DESCRIPTION
"Line type for DS2, E2
interfaces."
OBJECT dsx1Channelization
MIN-ACCESS read-only
DESCRIPTION
"The ability to set the channelization is not
r