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RFC1297

  1. RFC 1297
Network Working Group                                         D. Johnson
Request for Comments: 1297                           Merit Network, Inc.
                                                            January 1992


             NOC Internal Integrated Trouble Ticket System
                   Functional Specification Wishlist
                        ("NOC TT REQUIREMENTS")

Status of the Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard.  Distribution of this memo is
   unlimited.

Abstract

   Professional quality handling of network problems requires some kind
   of problem tracking system, herein referred to as a "trouble ticket"
   system.  A basic trouble ticket system acts like a hospital chart,
   coordinating the work of multiple people who may need to work on the
   problem.

   Once the basic trouble ticket system is in place, however, there are
   many extensions that can aid Network Operations efficiency.
   Information in the tickets can be used to produce statistical
   reports.  Operator efficiency and accuracy may be increased by
   automating trouble ticket entry with information from the network
   Alert system.  The Alert system may be used to monitor trouble ticket
   progress.  Trouble tickets may be also used to communicate network
   health information between NOCs, to telcom vendors, and to other
   internal sales and engineering audiences.

   This document explores competing uses, architectures, and desirable
   features of integrated internal trouble ticket systems for Network
   and other Operations Centers.

Introduction

   This RFC describes general functions of a Trouble Ticket system that
   could be designed for Network Operations Centers.  The document is
   being distributed to members of the Internet community in order to
   stimulate discussions of new production-oriented operator-level
   application tools for network operations.  Hopefully, this will
   result both in more ideas for improving NOC performance, and in more
   available tools that incorporate those ideas.





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PURPOSES OF A NOC TROUBLE TICKET SYSTEM

   A good Network Operations Trouble Ticket System should serve many
   purposes:

      1) SHORT-TERM MEMORY AND COMMUNICATION ("Hospital Chart").  The
      primary purpose of the trouble ticket system is to act as short-
      term memory about specific problems for the NOC as a whole.  In a
      multi-operator or multi-shift NOC, calls and problem updates come
      in without regard to who worked last on a particular problem.
      Problems extend over shifts, and problems may be addressed by
      several different operators on the same shift.  The trouble ticket
      (like a hospital chart) provides a complete history of the
      problem, so that any operator can come up to speed on a problem
      and take the next appropriate step without having to consult with
      other operators who are working on something else, or have gone
      home, or are on vacation.  In single-room NOCs, an operator may
      ask out loud if someone else knows about or is working on a
      problem, but the system should allow for more formal communication
      as well.

      2) SCHEDULING and WORK ASSIGNMENT.  NOCs typically work with many
      simultaneous problems with different priorities.  An on-line
      trouble ticket system can provide real time (or even constantly
      displayed and updated) lists of open problems, sorted by priority.
      This would allow operators to sort their work at the beginning of
      a shift, and to pick their next task during the shift.  It also
      would allow supervisors and operators to keep track of the current
      NOC workload, and to call in and assign additional staff as
      appropriate.

      It may be useful to allow current priorities of tickets change
      according to time of day, or in response to timer alerts.

      3) REFERRALS AND DISPATCHING.  If the trouble ticket system is
      thoroughly enough integrated with a mail system, or if the system
      is used by Network Engineers as well as Network Operators, then
      some problems can be dispatched simply by placing the appropriate
      Engineer or Operator name in an "assigned to" field of the trouble
      ticket.

      4) ALARM CLOCK.  Typically, most of the time a trouble ticket is
      open, it is waiting for something to happen.  There should almost
      always be a timer associated with every wait.  If a ticket is
      referred to a phone company, there will be an escalation time
      before which the phone company is supposed to call back with an
      update on the problem.  For tickets referred to remote site
      personnel, there may be other more arbitrary timeouts such as



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      "Monday morning".  Tickets referred to local engineers or
      programmers should also have timeouts ("Check in a couple of days
      if you don't hear back from me").  A good trouble ticket system
      will allow a timeout to be set for each ticket.  This alarm will
      generate an alert for that ticket at the appropriate time.
      Preferably, the system should allow text to be attached to that
      timer with a shorthand message about what the alert involves
      ("Remind Site: TT xxx") (The full story can always be found by
      checking the trouble ticket).  These alerts should feed into the
      NOC's standard alert system.

      The Alarm Clock can also assist (or enforce!) administrative
      escalation.  An escalation timer could automatically be set based
      on the type of network, severity of the problem, and the time the
      outage occurred.

      5) OVERSIGHT BY ENGINEERS AND CUSTOMER/SITE REPRESENTATIVES.  NOCs
      frequently operate more than one network, or at least have people
      (engineers, customer representatives, etc) who are responsible for
      subsets of the total network.  For these individual
      representatives, summaries of trouble tickets can be filtered by
      network or by node, and delivered electronically to the various
      engineers or site representatives.  Each of these reports includes
      a summary of the previous day's trouble tickets for those sites, a
      listing of older trouble tickets still open, and a section listing
      recurrent problems.  These reports allow the site reps to keep
      aware the current outages and trends for their particular sites.
      The trouble ticket system also allows network access to the the
      details of individual trouble tickets, so those receiving the
      general reports can get more detail on any of their problems by
      referencing the trouble ticket number.

      6) STATISTICAL ANALYSIS.  The fixed-form fields of trouble tickets
      allow categorizations of tickets, which are useful for analyzing
      equipment and NOC performance.  These include, Mean Time Between
      Failure and Mean Time to Repair reports for specific equipment.
      The fields may also be of use for generating statistical quality
      control reports, which allow deteriorating equipment to be
      detected and serviced before it fails completely.  Ticket
      breakdowns by network a NOC costs to be apportioned appropriately,
      and help in developing staffing and funding models.  A good
      trouble ticket system should make this statistical information in
      a format suitable for spreadsheets and graphics programs.

      7) FILTERING CURRENT ALERTS.  It would be possible to use network
      status information from the trouble ticket system to filter the
      alerts that are displayed on the alert system.  For instance, if
      node XXX is known to be down because the trouble ticket is



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      currently open on it, the alert display for that node could
      automatically be acknowledged.  Trouble tickets could potentially
      contain much further information useful for expert system analysis
      of current network alert information.

      8) ACCOUNTABILITY ("CYA"), FACILITATING CUSTOMER FOLLOW-THROUGH,
      AND NOC IMAGE).  Keeping user-complaint tickets facilities the
      kind of follow through with end-users that generates happy clients
      (and good NOC image) for normal trouble-fixing situations.  But
      also, by their nature, NOCs deal with crises; they occasionally
      find themselves with major outages, and angry users or
      administrators.  The trouble ticket system documents the NOC's
      (and the rest of the organization's) efforts to solve problems in
      case of complaints.

FIXED FIELDS, FREE-FORM FIELDS, and TT CONFIGURATION

   Information in trouble tickets can be placed in either fixed or
   freeform fields.  Fixed fields have the advantage that they can be
   used more easily for searches.  A series of fixed fields also acts as
   a template, either encouraging or requiring the operators to fill in
   certain standard data.  Fixed fields can facilitate data verification
   (e.g., making sure an entered name is in an attached contacts
   database, or verifying that a phone number consists of ten numeric
   characters).  Fixed fields are also appropriate for data that is
   automatically entered by the system, such as the operator's login id,
   the name of the node that was clicked on if the trouble ticket is
   opened via an alert tool, or names and phone numbers that are
   automatically entered into the ticket based on other entries (e.g.,
   filling in a contact name and phone based on a machine name).

   Unfortunately, fixed fields work best where the problem-debugging
   environment is uniform, well-understood, and stable; that is, trouble
   tickets work best when their fields are well tailored to the specific
   problem at hand.  It is easy to set up a large number of fields (or
   even required fields) that are irrelevant to a given problem; this
   slows down and confuses the operators.  Adding structure and validity
   checking to a field tends to make the data more consistent and
   reliable, but it also tends to force the operators into longer
   procedures like menus to get the get the data accepted by the system.
   It also forces there to be more maintenance on those verification
   systems (adding new entries as they become new legal options), and in
   some ways it reduces the accuracy of the system by forcing operators
   to choose "canned" or authorized responses that may not always
   represent the situation accurately.  Where statistical operational
   reports are a primary purpose of the trouble ticket system, several
   fixed fields may be appropriate.  If the primary intent of the system
   is to keep notes for individual problems and to facilitate



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   communication between operators, then fixed fields may tend to be a
   hindrance.  One reasonable guideline would be that fixed fields are
   used ONLY where they are automatically filled in by the larger
   system, or where the information in that field is explicitly used in
   a report or standard search procedure.

   Because of this close relationship between the structure of the
   ticket and the problem to be solved, it is very very useful to be
   able to define different ticket types for different classes of
   problems.  This becomes even more true for those many NOCs whose
   staff are responsible for other types of operations: mainframe
   operations, workstation administration, help desk functions, or any
   of the other real-time response functions.  Network operations to
   justify the expense of an operations center.  This kind of operation
   makes economic sense, and is becoming more prevalent.  In these kinds
   of situations it is vital that the same tools that are used for
   network operations also be available for the other operations.  This
   means that the trouble ticket configurations need to be modifiable by
   local staff.  Commercial RDBMS forms builder and report generator
   packages and "fourth-generation languages" offer a good start at
   this, although it is sometimes difficult to integrate full trouble
   ticket functionality through these systems.

TROUBLE TICKET STRUCTURE

   1) HEADERS.  Inevitably, a trouble ticket begins with a number of
   fixed fields.  These generally include:

      Time and Date of problem start.
      Initials or signon of the operator opening the ticket.
      Severity of the problem  (possibly separating the "customer
      severity" and the "NOC priority", since these could be different).
      A one-line description of the problem for use in reports.

   There can be many other fixed fields for specific purposes.  There
   may also be different kinds of tickets for different problems, where
   the ticket format differs mainly in fixed fields.  These include:

      Who reported the problem?  (Name, organization, phone,
                                                      email address)
      Machine(s) involved.
      Network involved (for multi-network NOCs).
      User's machine address.
      Destination machine address.
      Next Action.
      Time and date for alarm on this ticket.
      Who should the ticket be dispatched to?
      Ticket "owner" (one person designated to be responsible overall).



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   2) INCIDENT UPDATES.  The main body of trouble tickets is usually a
   series of freeform text fields.  Optimally, each of these fields is
   automatically marked with the time and date of the update, and with
   the signon of the operator making the update.  Since updates are
   frequently recorded sometime after the problem is fixed, however, it
   is useful to allow the operators to override the current time stamp
   with the time the update was actually made.  (In some
   implementations, both times will be kept internally).

   The first incident update usually is a description of the problem.
   Since the exact nature of the problem is usually not known when the
   ticket is first opened, this description may be complex and
   imprecise.  For problems that are reported by electronic mail, it is
   useful to be able to paste the original message in the ticket,
   particularly if it contains cryptic or extensive information (such as
   a user's traceroute output).  At least one such arbitrarily-long
   freeform field seems necessary to contain this kind of output,
   although it is better to allow arbitrarily long messages at any stage
   (e.g., so future complex messages can also be archived in the
   ticket).

   Subsequent update fields may be as simple as "Called site;  no
   answer".  Some systems allow these kinds of updates to be coded in
   fixed fields; most use freeform text.

   There should always be an indication of what the next action for this
   ticket ought to be.  Again, this may be implemented as a special
   fixed field, or by convention of using the last line of text.

   Advanced systems may also need a facility to allocate the amount of
   time a ticket is open between multiple sources.  A serious NOC will
   want to use its trouble ticket system to statistically track its
   performance on responding to problems. (e.g., Mean Time Between
   Failure and Mean Time To Repair reports).  Frequently, though,
   repairs are stopped at the customer's request.  ("It's not that
   important a machine and I don't feel like coming in--can you defer it
   until Monday Morning?").  In these cases the ticket needs to remain
   open, but there needs to be a notation that the ticket is now in
   "customer time" rather than "NOC time".  The durations of "customer
   time" need to be excluded from MTBF and MTTR reports.  Complicated
   repairs could move back and forth between "NOC time" "customer time"
   repeatedly.  This probably implies that each Incident Update may have
   a time and date of status change, and that these status changes can
   be read and aggregated by by reporting programs.

   3) RESOLUTION DATA.  Once a problem is resolved, it is useful to
   summarize the problem for future statistical analysis.  The following
   fields have been found to be useful:



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      - Time and Date of resulation (for outage duration).
      - Durations (can be calculated from time of resolution and
        incident report "customer/NOC time" stamps).
      - Resolution (one line of description of what happened, for
        reports).
      - Key component affected (for MTBF and similar reports).
      - Checked By -- a field for supervisors to sign off on ticket
        review.
      - Escalated to -- for reports on how many problems require
        non-NOC help.
      - Temp - a database field that can be used to store temporary
        "check marks" while making statistical investigations.

USER, TROUBLE, and ENGINEERING Ticket System(s)

   The primary level of an Network Operations trouble ticket is the
   "problem" or "trouble": a single malfunctioning piece of hardware or
   software that breaks at some time, has various efforts to fix it, and
   eventually is fixed at some given time.

   The primary level of an Network Information Center ticket, however,
   might well be the "user complaint".  A single network failure might
   well produce a large number of individual user phone calls and hence
   "user complaint" tickets.  A NIC may want to use tickets to track
   each one of these calls, e.g., to make sure each user is informed and
   satisfied about the eventual resolution of the single hardware
   problem.

   In addition, NOCs (or Engineering Staffs) may want to track
   systematic problems.  The staff may know, for instance, that a
   particular router is old and fragile, or that a particular section of
   their network doesn't have enough redundancy.  It may be useful to
   open an "Engineering Ticket" on these known problems, providing a
   place to record history and notes about the problem, for use in
   further engineering or funding discussions.

   Even further "Meta" tickets could be described, having to do with
   such issues as whether the current trouble ticket fields, reports,
   and operation procedures were sufficient to handle current problems.

   It would be very convenient to be able to build all of these systems
   on the same platform, and to allow each type of ticket to easily
   reference other types.  Multiple "user complaint" tickets, then,
   might might explicitly point to a single "trouble" ticket.  Multiple
   trouble tickets representing independent failures would then point to
   a single "engineering" ticket, which described the systematic
   problem.  Multiple engineering tickets could point to a single "meta"
   ticket, if appropriate.



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ASSISTED ENTRY AND DATA VERIFICATION

   Data (particularly in fixed fields) is only useful for searching if
   it is entered in consistent formats.  A trouble ticket system needs
   to help operators fill these fields with the correct format of
   information.  This can be done using assisted entry (menus of
   acceptable choices), verification routines which check against
   internal lists or external databases (see next section), or other
   computer checking.

   Some database systems allow a customized "help" screen to be
   associated with each field, helping new (and experienced) operators
   by making context-sensitive trouble ticket system documentation
   available at every field.

   Very complicated help or operator-guidance systems can be built out
   of Expert System technology.  This could be as simple as help
   screens, or help screens with database information inserted (e.g.,
   site contact names and phone numbers).  Or it could involve hints to
   the operator, based on current network conditions.  Or it might even
   ask the operator to run tests and to type in the results.  (See
   EXPERT SYSTEMS, below).

INTEGRATION

   To be maximally efficient and useful, a Trouble Ticket system needs
   to integrate well with most of the rest of the NOC tools.  These
   include:

      1) OPERATOR WINDOW ENVIRONMENT.  A NOC Operator needs access to
      many pieces of information simultaneously, and therefore is well
      served by a good windowing environment.  The Trouble Ticket system
      needs to run within this larger windowing system, so that the
      operator can debug, consult databases, use Email, field alerts,
      and keep an eye out for other emergencies while working on a
      trouble ticket.  It is also useful to be able to run two trouble
      ticket sessions simultaneously, for example, to allow an operator
      to search for related tickets while he is in the middle of
      updating another ticket.  Cut and Paste between these various
      screens is mandatory, to allow easy recording of technical details
      in the trouble tickets.

      2) ALERT MONITORING SYSTEM.  Trouble tickets are often opened in
      response to machine alerts; it ought to be easy to open a trouble
      ticket directly from the alert tool.  When a ticket is opened this
      way, information about the alert and the machine involved ought to
      be automatically filled into the ticket.  (There are various
      opinions about whether trouble tickets ought to be opened



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      automatically without operator intervention.  This operator's
      opinion is that an operator acknowledgement should be required,
      but this point is debated enough that designers of a new system
      probably should support either option).

      The Alarm Clock feature of the trouble ticket system also
      generates alerts.  These alerts ought to feed gracefully into the
      Alert Monitor system, so that the operators will get all of their
      alerts from one place.

      3) DATABASE CONNECTIONS.  A good trouble ticketing system will
      query NOC databases to automatically fill out trouble ticket
      fields where possible.  This can be used for:

      - Filling out Network Operator information (e.g., phone number)
        based on the NetOp's signon id.
      - Filling in contact information based on machine name.
      - Filling in circuit numbers based on link description.
      - Filling in alarm clock or escalation time fields based on the
        machine or link name and on time of day.
      - Filling in machine serial numbers based on configuration database.

      4) MACHINE QUERYABLE INFORMATION.  It could also be possible for a
      trouble ticket system to make standard queries of the network
      itself when a trouble ticket is opened: e.g., the system could
      request and store current machine configurations whenever a ticket
      was opened for that machine.  On some systems, hardware serial
      numbers are obtainable by software query directly to the machine.

      5) ELECTRONIC MAIL.  Problem notification often comes via
      electronic mail; it must be possible to easily open a ticket and
      include the original mail message within the ticket as part of the
      initial problem description.  When extremely technical messages
      come in from network engineers, it is useful to allow those
      messages to be included verbatim, rather than forcing less
      technical network operators to rephrase the messages or to force
      them into predefined formats.  Later update messages should also
      be easily includable.  Possibly: tickets could be opened
      automatically for mail messages to certain mailboxes.  A response
      system saying "Your request has been received and assigned ticket
      number ####" might be desirable.

      Information within trouble tickets must also be easily available
      (possibly just via the windowing system) for inclusion in Email
      messages to engineers and others.

      Scheduled (e.g., daily) reports must also be easily generated into
      the Email system.



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      6) DISPATCHING AND NOTIFICATION SYSTEMS.  An important real-time
      aspect of Network Operations is notifying users, technical
      contacts, and administrators of various classes of problems.  The
      rules for who gets notified of what can be very arbitrary and
      complex, and can involve electronic mail, notices in computer
      conferences, automatic beeper pages, and synthesized voice
      announcements.  It would be good for a trouble ticket system to
      provide for automatic (or operator initiated) notification of the
      appropriate channels for the current ticket (based on network,
      machine, severity of problem, duration of the problem, escalation
      guidelines, etc).

      Databases associated with the trouble ticket system may also have
      lists of specific people to contact about outages for particular
      machines.  These "who to inform" lists can facilitate customized
      notification messages directly from the trouble ticket system.

      It may also be possible to dispatch experts directly from the
      trouble tickets system.  IBM's ECCO system allows allows customers
      to directly dispatch Service Engineers from machine interactions.
      Many NOCs also use computer hooked to modems to automatically page
      engineers.  This kind of dispatching should be available from
      within the trouble ticket system (along with an automatic note
      into the trouble ticket that the engineer has been dispatched).

      7) OTHER TROUBLE TICKET SYSTEMS.  When the NOC generates a trouble
      ticket, it often immediately calls up a telco or another Internet
      NOC, who proceed to open their own ticket.  The Internet
      Engineering Task Force User Connectivity Working Group is also
      proposing a national trouble ticket tracking system, which would
      need updating from individual NOC trouble ticket systems.  A
      state-of-the-art trouble ticket system could have provisions for
      transferring tickets and ticket information in and out of other
      such systems.

      8) NETWORK ACCESS.  Some older trouble ticket systems assumed that
      anyone with a need to access the information would obtain a signon
      and learn to use that system.  The range of people with a need for
      trouble ticket information is now too great to allow this
      assumption.  A good system now needs to be able to support network
      query for tickets and summary reports, as well as Email delivery
      of scheduled reports.

      9) SUBROUTINE INTERFACE.  To allow for ad-hoc and currently
      unanticipated needs, the trouble ticket system needs to support a
      full-function set of subroutine calls.  These subroutines will
      allow construction of further trouble ticket functionality not yet
      specified.



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      10) EXPERT SYSTEMS.  Network debugging is a very promising area
      for expert system and artificial intelligence applications.  But
      such an algorithm should require access to the alert monitoring
      system, configuration and change control systems, to the network
      itself, and also to the information in the trouble ticket system.
      A good future system then needs to make this information available
      (probably via the subroutine interface mentioned above), and to
      also allow the Network Operators to invoke the artificially
      intelligent debugging from within a trouble ticket (including its
      output as part of the ticket dialogue).

      11) GRAPHICS/REPORT Capability.  Statistical and graphical
      displays about trouble ticket data need to be compatible with
      tools used to generate reports, news letters, etc.

OTHER CONSIDERATIONS:

      1) INTERACTIVE SPEED.  The system must be fast enough to be used
      interactively.  NetOps need to answer questions over the phone in
      real time; good answers cannot be given if every query takes a
      couple of minutes.  More importantly, the NetOps need the trouble
      ticket system in order to get information necessary to fix the
      network.  If looking for old or currently-open tickets takes more
      than a few seconds, it won't be done.  If updates take very long
      to make, then updates won't be recorded, or they will be recorded
      long after the event (with corresponding loss of accuracy).  (Our
      Operators have asked for a single-line "update this ticket with
      this message" utility that would let them avoid even retrieving
      the ticket for simple updates!)  Any time spent waiting reduces
      NetOp productivity and Network reliability.

      2) BACKUPS AND RELIABILITY.  The trouble ticket system is
      absolutely crucial to both immediate and long-term operation of
      the NOC.  Good systems could back up all data several times an
      hour to an auxiliary processor.  That processor should be
      accessible for immediate use in case of failure of the primary
      system.

      3) HISTORY AND ARCHIVING.  A trouble ticket system is a
      constantly-growing database system.  Old tickets need to be
      removed from the system at some interval (a year?  several years?)
      and archived.  These archives should also be restorable for long-
      term history processing.

      4) PRIVACY AND SECURITY.  The ability to enter, append, and modify
      tickets should be controlled by id and password.  Permissions
      should be specifiable on a per-field basis.  General read access
      to tickets (or portions of tickets) also needs to be restricted,



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      or else NetOps will be reluctant to be full and candid in their
      reporting.

UTILITY

   There are quite a few ideas in this "Wishlist".  Ultimately, what an
   Operations Center needs is a totally integrated set of tools which
   completely model all of its activities, and which integrates cleanly
   with all backup, peer, and vendor NOCs.  It is hard to imagine that
   this whole system could come out of a shrinkwrapped box, even without
   the local configuration.  But most of these facilities do exist, now,
   in some system.  Hopefully, this document will foster an ongoing
   discussion of ways in which NOC operator-level tools are used in real
   operations, and will encourage systems implementors and vendors to
   bring some of this functionality to the aid of real operations.  It
   might even inspire current Operations Centers to add useful features
   to their current operations.

Security Considerations

   This paper does not pose specific new security issues.  The systems
   described herein would be host database applications, however, or
   even distributed host database applications.  All of the normal
   security considerations for that kind of system would apply.
   Multiple classes of user access need to be specified for classes of
   ticket data.  Possible security threats include disclosure of network
   information, disclosure of confidential material (e.g., circuit
   numbers or home phone numbers), and denial of service to the Network
   Operations Center leading to degradation of network service.

Author's Address

   Dale S. Johnson
   Merit NOC
   1075 Beal Avenue
   Ann Arbor, MI 48109-2112

   Phone:  (313) 936-2270

   Email:  dsj@merit.edu

   Discussion/comments may be sent to noc-tt-req@merit.edu.  The list
   is maintained by noc-tt-req-request@merit.edu.








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  1. RFC 1297