Network Working Group R. Bergman Request for Comments: 2707 Dataproducts Corp. Category: Informational T. Hastings, Ed. Xerox Corporation S. Isaacson Novell, Inc. H. Lewis IBM Corp. November 1999 Job Monitoring MIB - V1.0 Status of this Memo This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (1999). All Rights Reserved. IESG Note This MIB module uses an unconventional scheme for modeling management information (on top of the SNMP model) which is unique to this MIB. The IESG recommends against using this document as an example for the design of future MIBs. The "Printer Working Group" industry consortium is not an IETF working group, and the IETF does not recognize the Printer Working Group as a standards-setting body. This document is being published solely to provide information to the Internet community regarding a MIB that might be deployed in the marketplace. Publication of this document as an RFC is not an endorsement of this MIB.Abstract
This document provides a printer industry standard SNMP MIB for (1) monitoring the status and progress of print jobs (2) obtaining resource requirements before a job is processed, (3) monitoring resource consumption while a job is being processed and (4) collecting resource accounting data after the completion of a job. This MIB is intended to be implemented (1) in a printer or (2) in a server that supports one or more printers. Use of the object set is not limited to printing. However, support for services other than printing is outside the scope of this Job Monitoring MIB. Future
extensions to this MIB may include, but are not limited to, fax machines and scanners.Table of Contents
1 INTRODUCTION 4 1.1 Types of Information in the MIB 5 1.2 Types of Job Monitoring Applications 6 2 TERMINOLOGY AND JOB MODEL 7 2.1 System Configurations for the Job Monitoring MIB 11 2.1.1 Configuration 1 - client-printer 11 2.1.2 Configuration 2 - client-server-printer - agent in the server 12 2.1.3 Configuration 3 - client-server-printer - client monitors printer agent and server 14 3 MANAGED OBJECT USAGE 15 3.1 Conformance Considerations 15 3.1.1 Conformance Terminology 16 3.1.2 Agent Conformance Requirements 16 3.1.2.1 MIB II System Group objects 17 3.1.2.2 MIB II Interface Group objects 17 3.1.2.3 Printer MIB objects 17 3.1.3 Job Monitoring Application Conformance Requirements 17 3.2 The Job Tables and the Oldest Active and Newest Active Indexes 18 3.3 The Attribute Mechanism and the Attribute Table(s) 20 3.3.1 Conformance of Attribute Implementation 21 3.3.2 Useful, 'Unknown', and 'Other' Values for Objects and Attributes 21 3.3.3 Index Value Attributes 22 3.3.4 Data Sub-types and Attribute Naming Conventions 22 3.3.5 Single-Value (Row) Versus Multi-Value (MULTI-ROW) Attributes 23 3.3.6 Requested Objects and Attributes 23 3.3.7 Consumption Attributes 24 3.3.8 Attribute Specifications 24 3.3.9 Job State Reason bit definitions 43 3.3.9.1 JmJobStateReasons1TC specification 44 3.3.9.2 JmJobStateReasons2TC specification 47 3.3.9.3 JmJobStateReasons3TC specification 51 3.3.9.4 JmJobStateReasons4TC specification 51 3.4 Monitoring Job Progress 51 3.5 Job Identification 55 3.5.1 The Job Submission ID specifications 56 3.6 Internationalization Considerations 60 3.6.1 Text generated by the server or device 61 3.6.2 Text supplied by the job submitter 61 3.6.3 'DateAndTime' for representing the date and time 63
3.7 IANA and PWG Registration Considerations 63 3.7.1 PWG Registration of enums 63 3.7.1.1 Type 1 enumerations 64 3.7.1.2 Type 2 enumerations 64 3.7.1.3 Type 3 enumeration 64 3.7.2 PWG Registration of type 2 bit values 65 3.7.3 PWG Registration of Job Submission Id Formats 65 3.7.4 PWG Registration of MIME types/sub-types for document- formats 65 3.8 Security Considerations 65 3.8.1 Read-Write objects 65 3.8.2 Read-Only Objects In Other User's Jobs 66 3.9 Notifications 66 4 MIB SPECIFICATION 67 Textual conventions for this MIB module 68 JmUTF8StringTC 68 JmJobStringTC 68 JmNaturalLanguageTagTC 68 JmTimeStampTC 69 JmJobSourcePlatformTypeTC 69 JmFinishingTC 70 JmPrintQualityTC 71 JmPrinterResolutionTC 71 JmTonerEconomyTC 72 JmBooleanTC 72 JmMediumTypeTC 72 JmJobCollationTypeTC 74 JmJobSubmissionIDTypeTC 74 JmJobStateTC 75 JmAttributeTypeTC 78 JmJobServiceTypesTC 81 JmJobStateReasons1TC 83 JmJobStateReasons2TC 83 JmJobStateReasons3TC 83 JmJobStateReasons4TC 84 The General Group (MANDATORY) 84 jmGeneralJobSetIndex (Int32(1..32767)) 85 jmGeneralNumberOfActiveJobs (Int32(0..)) 86 jmGeneralOldestActiveJobIndex (Int32(0..)) 86 jmGeneralNewestActiveJobIndex (Int32(0..)) 86 jmGeneralJobPersistence (Int32(15..)) 87 jmGeneralAttributePersistence (Int32(15..)) 87 jmGeneralJobSetName (UTF8String63) 88 The Job ID Group (MANDATORY) 88 jmJobSubmissionID (OCTET STRING(SIZE(48))) 89 jmJobIDJobSetIndex (Int32(0..32767)) 90 jmJobIDJobIndex (Int32(0..)) 91 The Job Group (MANDATORY) 91
jmJobIndex (Int32(1..)) 92 jmJobState (JmJobStateTC) 92 jmJobStateReasons1 (JmJobStateReasons1TC) 93 jmNumberOfInterveningJobs (Int32(-2..)) 93 jmJobKOctetsPerCopyRequested (Int32(-2..)) 94 jmJobKOctetsProcessed (Int32(-2..)) 94 jmJobImpressionsPerCopyRequested (Int32(-2..)) 95 jmJobImpressionsCompleted (Int32(-2..)) 96 jmJobOwner (JobString63) 96 The Attribute Group (MANDATORY) 97 jmAttributeTypeIndex (JmAttributeTypeTC) 98 jmAttributeInstanceIndex (Int32(1..32767)) 99 jmAttributeValueAsInteger (Int32(-2..)) 99 jmAttributeValueAsOctets (Octets63) 100 5 APPENDIX A - IMPLEMENTING THE JOB LIFE CYCLE 104 6 APPENDIX B - SUPPORT OF JOB SUBMISSION PROTOCOLS 105 7 REFERENCES 105 8 NOTICES 108 9 AUTHORS' ADDRESSES 109 10 INDEX 111 11 Full Copyright Statement 1141 Introduction
This specification defines an official Printer Working Group (PWG) [PWG] standard SNMP MIB for the monitoring of jobs on network printers. This specification is being published as an IETF Information Document for the convenience of the Internet community. In consultation with the IETF Application Area Directors, it was concluded that this MIB specification properly belongs as an Information document, because this MIB monitors a service node on the network, rather than a network node proper. The Job Monitoring MIB is intended to be implemented by an agent within a printer or the first server closest to the printer, where the printer is either directly connected to the server only or the printer does not contain the job monitoring MIB agent. It is recommended that implementations place the SNMP agent as close as possible to the processing of the print job. This MIB applies to printers with and without spooling capabilities. This MIB is designed to be compatible with most current commonly-used job submission protocols. In most environments that support high function job submission/job control protocols, like ISO DPA [iso- dpa], those protocols would be used to monitor and manage print jobs rather than using the Job Monitoring MIB.
The Job Monitoring MIB consists of a General Group, a Job Submission ID Group, a Job Group, and an Attribute Group. Each group is a table. All accessible objects are read-only. The General Group contains general information that applies to all jobs in a job set. The Job Submission ID table maps the job submission ID that the client uses to identify a job to the jmJobIndex that the Job Monitoring Agent uses to identify jobs in the Job and Attribute tables. The Job table contains the MANDATORY integer job state and status objects. The Attribute table consists of multiple entries per job that specify (1) job and document identification and parameters, (2) requested resources, and (3) consumed resources during and after job processing/printing. A larger number of job attributes are defined as textual conventions that an agent SHALL return if the server or device implements the functionality so represented and the agent has access to the information.1.1 Types of Information in the MIB
The job MIB is intended to provide the following information for the indicated Role Models in the Printer MIB [print-mib] (Appendix D - Roles of Users). User: Provide the ability to identify the least busy printer. The user will be able to determine the number and size of jobs waiting for each printer. No attempt is made to actually predict the length of time that jobs will take. Provide the ability to identify the current status of the user's job (user queries). Provide a timely indication that the job has completed and where it can be found. Provide error and diagnostic information for jobs that did not successfully complete. Operator: Provide a presentation of the state of all the jobs in the print system. Provide the ability to identify the user that submitted the print job. Provide the ability to identify the resources required by each job.
Provide the ability to define which physical printers are candidates for the print job. Provide some idea of how long each job will take. However, exact estimates of time to process a job is not being attempted. Instead, objects are included that allow the operator to be able to make gross estimates. Capacity Planner: Provide the ability to determine printer utilization as a function of time. Provide the ability to determine how long jobs wait before starting to print. Accountant: Provide information to allow the creation of a record of resources consumed and printer usage data for charging users or groups for resources consumed. Provide information to allow the prediction of consumable usage and resource need. The MIB supports printers that can contain more than one job at a time, but still be usable for low end printers that only contain a single job at a time. In particular, the MIB supports the needs of Windows and other PC environments for managing low-end direct-connect (serial or parallel) and networked devices without unnecessary overhead or complexity, while also providing for higher end systems and devices.1.2 Types of Job Monitoring Applications
The Job Monitoring MIB is designed for the following types of monitoring applications: 1. Monitor a single job starting when the job is submitted and ending a defined period after the job completes. The Job Submission ID table provides the map to find the specific job to be monitored. 2. Monitor all 'active' jobs in a queue, which this specification generalizes to a "job set". End users may use such a program when selecting a least busy printer, so the MIB is designed for such a program to start up quickly and find the information needed quickly without having to read
all (completed) jobs in order to find the active jobs. System operators may also use such a program, in which case it would be running for a long period of time and may also be interested in the jobs that have completed. Finally such a program may be used to provide an enhanced console and logging capability. 3. Collect resource usage for accounting or system utilization purposes that copy the completed job statistics to an accounting system. It is recognized that depending on accounting programs to copy MIB data during the job-retention period is somewhat unreliable, since the accounting program may not be running (or may have crashed). Such a program is also expected to keep a shadow copy of the entire Job Attribute table including completed, canceled, and aborted jobs which the program updates on each polling cycle. Such a program polls at the rate of the persistence of the Attribute table. The design is not optimized to help such an application determine which jobs are completed, canceled, or aborted. Instead, the application SHOULD query each job that the application's shadow copy shows was not complete, canceled, or aborted at the previous poll cycle to see if it is now complete or canceled, plus any new jobs that have been submitted. The MIB provides a set of objects that represent a compatible subset of job and document attributes of the ISO DPA standard [iso-dpa] and the Internet Printing Protocol (IPP) [ipp-model], so that coherence is maintained between these two protocols and the information presented to end users and system operators by monitoring applications. However, the job monitoring MIB is intended to be used with printers that implement other job submitting and management protocols, such as IEEE 1284.1 (TIPSI) [tipsi], as well as with ones that do implement ISO DPA. Thus the job monitoring MIB does not require implementation of either the ISO DPA or IPP protocols. The MIB is designed so that an additional MIB(s) can be specified in the future for monitoring multi-function (scan, FAX, copy) jobs as an augmentation to this MIB.2 Terminology and Job Model
This section defines the terms that are used in this specification and the general model for jobs in alphabetical order.
NOTE - Existing systems use conflicting terms, so these terms are drawn from the ISO 10175 Document Printing Application (DPA) standard [iso-dpa]. For example, PostScript systems use the term session for what is called a job in this specification and the term job to mean what is called a document in this specification. Accounting Application: The SNMP management application that copies job information to some more permanent medium so that another application can perform accounting on the data for Accountants, Asset Managers, and Capacity Planners use. Agent: The network entity that accepts SNMP requests from a monitor or accounting application and provides access to the instrumentation for managing jobs modeled by the management objects defined in the Job Monitoring MIB module for a server or a device. Attribute: A name, value-pair that specifies a job or document instruction, a status, or a condition of a job or a document that has been submitted to a server or device. A particular attribute NEED NOT be present in each job instance. In other words, attributes are present in a job instance only when there is a need to express the value, either because (1) the client supplied a value in the job submission protocol, (2) the document data contained an embedded attribute, or (3) the server or device supplied a default value. An agent MAY represent an attribute as an entry (row) in the Attribute table in this MIB in which entries are present only when necessary. Attributes are identified in this MIB by an enum. Client: The network entity that end users use to submit jobs to spoolers, servers, or printers and other devices, depending on the configuration, using any job submission protocol over a serial or parallel port to a directly-connected device or over the network to a networked-connected device. Device: A hardware entity that (1) interfaces to humans, such as a device that produces marks on paper or scans marks on paper to produce an electronic representation, (2) accesses digital media, such as CD-ROMs, or (3) interfaces electronically to another device, such as sends FAX data to another FAX device. Document: A sub-section within a job that contains print data and document instructions that apply to just the document. Document Instruction: An instruction specifying how to process the document. Document instructions MAY be passed in the job submission protocol separate from the actual document data, or MAY be embedded in the document data or a combination, depending on the job submission protocol and implementation.
End User: A user that uses a client to submit a print job. See "user". Impression: For a print job, an impression is the passage of the entire side of a sheet by the marker, whether or not any marks are made and independent of the number of passes that the side makes past the marker. Thus a four pass color process counts as a single impression, as does highlight color. Impression counters count all kinds: monochrome, highlight color, and full process color, while full color counters only count full color impressions, and high light color counters only count high light color impressions. One-sided processing involves one impression per sheet. Two-sided processing involves two impressions per sheet. If a two-sided document has an odd number of pages, the last sheet still counts as two impressions, if that sheet makes two passes through the marker or the marker marks on both sides of a sheet in a single pass. Two-up printing is the placement of two logical pages on one side of a sheet and so is still a single impression. See "page" and "sheet". NOTE - Since impressions include blank sides, it is suggested that accounting application implementers consider charging for sheets, rather than impressions, possibly using the value of the sides attribute to select different charges for one-sided versus two-sided printing, since some users may think that impressions don't include blank sides. Internal Collation: The production of the sheets for each document copy performed within the printing device by making multiple passes over either the source or an intermediate representation of the document. Job: A unit of work whose results are expected together without interjection of unrelated results. A job contains one or more documents. Job Accounting: The activity of a management application of accessing the MIB and recording what happens to the job during and after the processing of the job. Job Instruction: An instruction specifying how, when, or where the job is to be processed. Job instructions MAY be passed in the job submission protocol or MAY be embedded in the document data or a combination depending on the job submission protocol and implementation.
Job Monitoring (using SNMP): The activity of a management application of accessing the MIB and (1) identifying jobs in the job tables being processed by the server, printer or other devices, and (2) displaying information to the user about the processing of the job. Job Monitoring Application: The SNMP management application that End Users, and System Operators use to monitor jobs using SNMP. A monitor MAY be either a separate application or MAY be part of the client that also submits jobs. See "monitor". Job Set: A group of jobs that are queued and scheduled together according to a specified scheduling algorithm for a specified device or set of devices. For implementations that embed the SNMP agent in the device, the MIB job set normally represents all the jobs known to the device, so that the implementation only implements a single job set. If the SNMP agent is implemented in a server that controls one or more devices, each MIB job set represents a job queue for (1) a specific device or (2) set of devices, if the server uses a single queue to load balance between several devices. Each job set is disjoint; no job SHALL be represented in more than one MIB job set. Monitor: Short for Job Monitoring Application. Page: A page is a logical division of the original source document. Number up is the imposition of more than one page on a single side of a sheet. See "impression" and "sheet" and "two-up". Proxy: An agent that acts as a concentrator for one or more other agents by accepting SNMP operations on the behalf of one or more other agents, forwarding them on to those other agents, gathering responses from those other agents and returning them to the original requesting monitor. Queuing: The act of a device or server of ordering (queuing) the jobs for the purposes of scheduling the jobs to be processed. Printer: A device that puts marks on media. Server: A network entity that accepts jobs from clients and in turn submits the jobs to printers and other devices that may be directly connected to the server via a serial or parallel port or may be on the network. A server MAY be a printer supervisor control program, or a print spooler. Sheet: A sheet is a single instance of a medium, whether printing on one or both sides of the medium. See "impression" and "page".
SNMP Information Object: A name, value-pair that specifies an action, a status, or a condition in an SNMP MIB. Objects are identified in SNMP by an OBJECT IDENTIFIER. Spooler: A server that accepts jobs, spools the data, and decides when and on which printer to print the job. A spooler is a client to a printer or a printer supervisor, depending on implementation. Spooling: The act of a device or server of (1) accepting jobs and (2) writing the job's attributes and document data on to secondary storage. Stacked: When a media sheet is placed in an output bin of a device. Supervisor: A server that contains a control program that controls a printer or other device. A supervisor is a client to the printer or other device. System Operator: A user that uses a monitor to monitor the system and carries out tasks to keep the system running. System Administrator: A user that specifies policy for the system. Two-up: The placement of two pages on one side of a sheet so that each side or impressions counts as two pages. See "page" and "sheet". User: A person that uses a client or a monitor. See "end user".2.1 System Configurations for the Job Monitoring MIB
This section enumerates the three configurations in which the Job Monitoring MIB is intended to be used. To simplify the pictures, the devices are shown as printers. See section 1.1 entitled "Types of Information in the MIB". The diagram in the Printer MIB [print-mib] entitled: "One Printer's View of the Network" is assumed for this MIB as well. Please refer to that diagram to aid in understanding the following system configurations.2.1.1 Configuration 1 - client-printer
In the client-printer configuration 1, the client(s) submit jobs directly to the printer, either by some direct connect, or by network connection.
The job submitting client and/or monitoring application monitor jobs by communicating directly with an agent that is part of the printer. The agent in the printer SHALL keep the job in the Job Monitoring MIB as long as the job is in the printer, plus a defined time period after the job enters the completed state in which accounting programs can copy out the accounting data from the Job Monitoring MIB. all end-user ######## SNMP query +-------+ +--------+ ---- job submission |monitor| | client | +---#---+ +--#--+--+ # # | # ############ | # # | +==+===#=#=+==+ | | | agent | | | | +-------+ | | | PRINTER <--------+ | | Print Job Delivery Channel | | +=============+ Figure 2-1 - Configuration 1 - client-printer - agent in the printer The Job Monitoring MIB is designed to support the following relationships (not shown in Figure 2-1): 1. Multiple clients MAY submit jobs to a printer. 2. Multiple clients MAY monitor a printer. 3. Multiple monitors MAY monitor a printer. 4. A client MAY submit jobs to multiple printers. 5. A monitor MAY monitor multiple printers.2.1.2 Configuration 2 - client-server-printer - agent in the server
In the client-server-printer configuration 2, the client(s) submit jobs to an intermediate server by some network connection, not directly to the printer. While configuration 2 is included, the design center for this MIB is configurations 1 and 3. The job submitting client and/or monitoring application monitor jobs by communicating directly with: A Job Monitoring MIB agent that is part of the server (or a front for the server)
There is no SNMP Job Monitoring MIB agent in the printer in configuration 2, at least that the client or monitor are aware. In this configuration, the agent SHALL return the current values of the objects in the Job Monitoring MIB both for jobs the server keeps and jobs that the server has submitted to the printer. The Job Monitoring MIB agent obtains the required information from the printer by a method that is beyond the scope of this document. The agent in the server SHALL keep the job in the Job Monitoring MIB in the server as long as the job is in the printer, plus a defined time period after the job enters the completed state in which accounting programs can copy out the accounting data from the Job Monitoring MIB. all end-user +-------+ +----------+ |monitor| | client | ######## SNMP query +---+---# +---#----+-+ **** non-SNMP cntrl # # | ---- job submission # # | # # | #=====#=+==v==+ | agent | | +-------+ | | server | +----+-----+--+ control * | ********** | * | +========v====+ | | | | | | | | PRINTER <---------+ | | Print Job Delivery Channel | | +=============+ Figure 2-2 - Configuration 2 - client-server-printer - agent in the server The Job Monitoring MIB is designed to support the following relationships (not shown in Figure 2-2): 1. Multiple clients MAY submit jobs to a server. 2. Multiple clients MAY monitor a server. 3. Multiple monitors MAY monitor a server. 4. A client MAY submit jobs to multiple servers. 5. A monitor MAY monitor multiple servers. 6. Multiple servers MAY submit jobs to a printer. 7. Multiple servers MAY control a printer.
2.1.3 Configuration 3 - client-server-printer - client monitors printer agent and server
In the client-server-printer configuration 3, the client(s) submit jobs to an intermediate server by some network connection, not directly to the printer. That server does not contain a Job Monitoring MIB agent. The job submitting client and/or monitoring application monitor jobs by communicating directly with: 1. The server using some undefined protocol to monitor jobs in the server (that does not contain the Job Monitoring MIB) AND 2. A Job Monitoring MIB agent that is part of the printer to monitor jobs after the server passes the jobs to the printer. In such configurations, the server deletes its copy of the job from the server after submitting the job to the printer usually almost immediately (before the job does much processing, if any). In configuration 3, the agent (in the printer) SHALL keep the values of the objects in the Job Monitoring MIB that the agent implements updated for a job that the server has submitted to the printer. The agent SHALL obtain information about the jobs submitted to the printer from the server (either in the job submission protocol, in the document data, or by direct query of the server), in order to populate some of the objects the Job Monitoring MIB in the printer. The agent in the printer SHALL keep the job in the Job Monitoring MIB as long as the job is in the Printer, and longer in order to implement the completed state in which monitoring programs can copy out the accounting data from the Job Monitoring MIB.
all end-user +-------+ +----------+ |monitor| | client | ######## SNMP query +---+---* +---*----+-+ **** non-SNMP query # * * | ---- job submission # * * | # * * | # *=====v====v==+ # | | # | server | # | | # +----#-----+--+ # optional# | # ########## | # # | +==+=v===v=+==+ | | | agent | | | | +-------+ | | | PRINTER <---------+ | | Print Job Delivery Channel | | +=============+ Figure 2-3 - Configuration 3 - client-server-printer - client monitors printer agent and server The Job Monitoring MIB is designed to support the following relationships (not shown in Figure 2-3): 1. Multiple clients MAY submit jobs to a server. 2. Multiple clients MAY monitor a server. 3. Multiple monitors MAY monitor a server. 4. A client MAY submit jobs to multiple servers. 5. A monitor MAY monitor multiple servers. 6. Multiple servers MAY submit jobs to a printer. 7. Multiple servers MAY control a printer.3 Managed Object Usage
This section describes the usage of the objects in the MIB.3.1 Conformance Considerations
In order to achieve interoperability between job monitoring applications and job monitoring agents, this specification includes the conformance requirements for both monitoring applications and agents.
3.1.1 Conformance Terminology
This specification uses the verbs: "SHALL", "SHOULD", "MAY", and "NEED NOT" to specify conformance requirements according to RFC 2119 [RFC2119] as follows: "SHALL": indicates an action that the subject of the sentence must implement in order to claim conformance to this specification "MAY": indicates an action that the subject of the sentence does not have to implement in order to claim conformance to this specification, in other words that action is an implementation option "NEED NOT": indicates an action that the subject of the sentence does not have to implement in order to claim conformance to this specification. The verb "NEED NOT" is used instead of "may not", since "may not" sounds like a prohibition. "SHOULD": indicates an action that is recommended for the subject of the sentence to implement, but is not required, in order to claim conformance to this specification.3.1.2 Agent Conformance Requirements
A conforming agent: 1. SHALL implement all MANDATORY groups in this specification. 2. SHALL implement any attributes if (1) the server or device supports the functionality represented by the attribute and (2) the information is available to the agent. 3. SHOULD implement both forms of an attribute if it implements an attribute that permits a choice of INTEGER and OCTET STRING forms, since implementing both forms may help management applications by giving them a choice of representations, since the representation are equivalent. See the JmAttributeTypeTC textual-convention. NOTE - This MIB, like the Printer MIB, is written following the subset of SMIv2 that can be supported by SMIv1 and SNMPv1 implementations.
3.1.2.1 MIB II System Group objects
The Job Monitoring MIB agent SHALL implement all objects in the System Group of MIB-II [mib-II], whether the Printer MIB [print-mib] is implemented or not.3.1.2.2 MIB II Interface Group objects
The Job Monitoring MIB agent SHALL implement all objects in the Interfaces Group of MIB-II [mib-II], whether the Printer MIB [print- mib] is implemented or not.3.1.2.3 Printer MIB objects
If the agent is providing access to a device that is a printer, the agent SHALL implement all of the MANDATORY objects in the Printer MIB [print-mib] and all the objects in other MIBs that conformance to the Printer MIB requires, such as the Host Resources MIB [hr-mib]. If the agent is providing access to a server that controls one or more direct-connect or networked printers, the agent NEED NOT implement the Printer MIB and NEED NOT implement the Host Resources MIB.3.1.3 Job Monitoring Application Conformance Requirements
A conforming job monitoring application: 1. SHALL accept the full syntactic range for all objects in all MANDATORY groups and all MANDATORY attributes that are required to be implemented by an agent according to Section 3.1.2 and SHALL either present them to the user or ignore them. 2. SHALL accept the full syntactic range for all attributes, including enum and bit values specified in this specification and additional ones that may be registered with the PWG and SHALL either present them to the user or ignore them. In particular, a conforming job monitoring application SHALL not malfunction when receiving any standard or registered enum or bit values. See Section 3.7 entitled "IANA and PWG Registration Considerations". 3. SHALL NOT fail when operating with agents that materialize attributes after the job has been submitted, as opposed to when the job is submitted. 4. SHALL, if it supports a time attribute, accept either form of the time attribute, since agents are free to implement either time form.
3.2 The Job Tables and the Oldest Active and Newest Active Indexes
The jmJobTable and jmAttributeTable contain objects and attributes, respectively, for each job in a job set. These first two indexes are: 1. jmGeneralJobSetIndex - which job set 2. jmJobIndex - which job in the job set In order for a monitoring application to quickly find that active jobs (jobs in the pending, processing, or processingStopped states), the MIB contains two indexes: 1. jmGeneralOldestActiveJobIndex - the index of the active job that has been in the tables the longest. 2. jmGeneralNewestActiveJobIndex - the index of the active job that has been most recently added to the tables. The agent SHALL assign the next incremental value of jmJobIndex to the job, when a new job is accepted by the server or device to which the agent is providing access. If the incremented value of jmJobIndex would exceed the implementation-defined maximum value for jmJobIndex, the agent SHALL 'wrap' back to 1. An agent uses the resulting value of jmJobIndex for storing information in the jmJobTable and the jmAttributeTable about the job. It is recommended that the largest value for jmJobIndex be much larger than the maximum number of jobs that the implementation can contain at a single time, so as to minimize the premature re-use of a jmJobIndex value for a newer job while clients retain the same ' stale' value for an older job. It is recommended that agents that are providing access to servers/devices that already allocate job-identifiers for jobs as integers use the same integer value for the jmJobIndex. Then management applications using this MIB and applications using other protocols will see the same job identifiers for the same jobs. Agents providing access to systems that contain jobs with a job identifier of 0 SHALL map the job identifier value 0 to a jmJobIndex value that is one higher than the highest job identifier value that any job can have on that system. Then only job 0 will have a different job-identifier value than the job's jmJobIndex value. NOTE - If a server or device accepts jobs using multiple job submission protocols, it may be difficult for the agent to meet the recommendation to use the job-identifier values that the server or
device assigns as the jmJobIndex value, unless the server/device assigns job-identifiers for each of its job submission protocols from the same job-identifier number space. Each time a new job is accepted by the server or device that the agent is providing access to AND that job is to be 'active' (pending, processing, or processingStopped, but not pendingHeld), the agent SHALL copy the value of the job's jmJobIndex to the jmGeneralNewestActiveJobIndex object. If the new job is to be ' inactive' (pendingHeld state), the agent SHALL not change the value of jmGeneralNewestActiveJobIndex object (though the agent SHALL assign the next incremental jmJobIndex value to the job). When a job transitions from one of the 'active' job states (pending, processing, processingStopped) to one of the 'inactive' job states (pendingHeld, completed, canceled, or aborted), with a jmJobIndex value that matches the jmGeneralOldestActiveJobIndex object, the agent SHALL advance (or wrap) the value to the next oldest 'active' job, if any. See the JmJobStateTC textual-convention for a definition of the job states. Whenever a job transitions from one of the 'inactive' job states to one of the 'active' job states (from pendingHeld to pending or processing), the agent SHALL update the value of either the jmGeneralOldestActiveJobIndex or the jmGeneralNewestActiveJobIndex objects, or both, if the job's jmJobIndex value is outside the range between jmGeneralOldestActiveJobIndex and jmGeneralNewestActiveJobIndex. When all jobs become 'inactive', i.e., enter the pendingHeld, completed, canceled, or aborted states, the agent SHALL set the value of both the jmGeneralOldestActiveJobIndex and jmGeneralNewestActiveJobIndex objects to 0. NOTE - Applications that wish to efficiently access all of the active jobs MAY use jmGeneralOldestActiveJobIndex value to start with the oldest active job and continue until they reach the index value equal to jmGeneralNewestActiveJobIndex, skipping over any pendingHeld, completed, canceled, or aborted jobs that might intervene. If an application detects that the jmGeneralNewestActiveJobIndex is smaller than jmGeneralOldestActiveJobIndex, the job index has wrapped. In this case, the application SHALL reset the index to 1 when the end of the table is reached and continue the GetNext operations to find the rest of the active jobs.
NOTE - Applications detect the end of the jmAttributeTable table when the OID returned by the GetNext operation is an OID in a different MIB. There is no object in this MIB that specifies the maximum value for the jmJobIndex supported by the implementation. When the server or device is power-cycled, the agent SHALL remember the next jmJobIndex value to be assigned, so that new jobs are not assigned the same jmJobIndex as recent jobs before the power cycle.