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Network Working Group                                         A. BressenRequest for Comments: 2321                      Cohesive Network SystemsCategory: Informational                                     1 April 1998RITA -- The Reliable Internetwork Troubleshooting AgentStatus 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 (1998).  All Rights Reserved.Abstract   A Description of the usage of Nondeterministic Troubleshooting and   Diagnostic Methodologies as applied to today's complex   nondeterministic networks and environments.1. Introduction   Increasingly, IETF efforts have been devoted to aiding network   management, troubleshooting, and diagnosis. Results have included   SNMP, cflowd, and RMON, and ongoing projects at the time of this   writing include Universal Logging Protocol and Distributed   Management.  These tools work well within the horizon of   deterministic situations in which the configuration of the network or   relevant components is known or can be relatively easily determined.   They do not well address many problems that are related to the   complex internetworks we have today, such as:     o  Networks where the root bridge for a world-wide bridged        network is suboptimally located, such as under the desk of a        secretary who kicks off her shoes when she arrives in the        morning.     o  Networks where a hub is located adjacent to a monitor that        emits disruptive RF when displaying certain graphics.     o  Networks where an ISP and several of their customers use        network 10.0.0.0 internally and do not hide RIP broadcasts from        one another.     o  Networks where gateways are data-sensitive     o  Networks where vendors inadvertently ship units with        duplicate MAC addresses to the same end-user or where all users        have a tool for changing MAC addresses.Bressen                      Informational                      [Page 1]

RFC 2321                          RITA                      1 April 1998   In this document we introduce a new hardware-based tool for diagnosis   and repair of network related hardware and software problems. This   tool is best suited to addressing nondeterministic problems such as   those described above. This tool has broad areas of application at   all levels of the OSI model; in addition to uses in the physical,   network, transport and application layers, it has been used to   successfully address problems at the political and religious layers   as well. RITA, the Reliable Internet Troubleshooting Agent, was   developed initially at The Leftbank Operation (now known as Cohesive   Network Systems, New England Division) based on a hardware platform   supplied by Archie McPhee (Reference [1]). A typical RITA unit is   depicted in Figure 1.         comb      neck             body                    feet          |         |                |                       |          v         v                V                       V           ,^/'/,           ,______________________.         ,         i'  '  /          /                       =========<-        / <o>   `---------/                        \         `      .;__.  ,__,--------.                         /         ,         / ,/ vv          \                        =========<-        '-'                `-----------------------'         `         ^     ^                                     ^         |     |                                     |        beak  wattles                               legs                                 Figure 1.2. Specification   A typical RITA is 51.25 cm long and yellow-orange in color.  Either   natural or artificial substances may be used for construction.  RITA   has very flexible characteristics, and thus can interoperate within   fairly broad parameters.  Unlike most other tools described in   forthcoming RFC's, RITA does not require any IANA namespace   management.  It is not anticipated that versions will be   incompatible, thus no versioning field is present. Interoperability   testing may be conducted at a future meeting of the IETF.3. Diagnostic Usage:   RITA may be applied in two diagnostic fashions, however only one of   these methods, described below in 3.1, has been refined to a state   such that we feel comfortable publishing the methodology.Bressen                      Informational                      [Page 2]

RFC 2321                          RITA                      1 April 1998   3.1   The first method provides a broad-spectrum evaluation of   quality of the entity tested, and is thus known as the BS eval test.   This method can be used with great success on both deterministic and   non-deterministic problems.  Testing is performed by placing the RITA   unit on top of a suspect piece of hardware, or, in the case of   software, placing the unit on a packaged copy of the program, or hard   copy of the source code.   If the RITA does not get up and fly away, the hardware or software   being tested is misconfigured, fubar, or broken as designed. While   this method does identify all equipment and software as sub-optimal,   Sturgeon's Law (see reference [5]) indicates that at least 90% of   these results are accurate, and it is felt that a maximum 10% false   positive result is within acceptable parameters.   3.2 The second method involves applications of traditional techniques   of haruspication (see reference [3]) and to date has been practiced   with much greater success using implements other than RITA. The   absence of entrails in the RITA unit may contribute to this; future   design enhancements may address this issue by the addition of   artificial giblets.   An alternative approach that has been discarded involved cleromantic   principles (see reference [3]), and was known as "flipping the bird".4. Corrective Usage:   Corrective usage of RITA is most successful in dealing with the most   difficult class of networking problems: those that seem to exhibit   sporadic, non-deterministic behavior.   RITA units enhance normal corrective measures of these problems,   methods such as rebooting, reseating of components and connectors,   changing tabs to spaces or vice-versa in configuration files, blaming   third-party vendors, and use of ballistic implements to effect   wholesale displacement of systems and software, to at least 100% of   their normal efficacy.    Specific Problem Methodologies:     o  Physical Layer: Wave RITA unit towards malfunctioning        components.     o  Network Layer: Wave RITA unit towards malfunctioning        components.     o  Transport Layer: Wave RITA unit towards malfunctioning        components.Bressen                      Informational                      [Page 3]

RFC 2321                          RITA                      1 April 1998     o  Application Layer: Strike product vendor representative        (or programmer, if available) with RITA, preferably on the top        of the skull, while shouting, "Read The Fine RFC's comma darn        it!"     o  Political Layer: Strike advocates of disruptive or        obstructive policies with RITA, preferably on the top of the        skull. In extreme cases insertion of RITA into bodily apertures        may become necessary. WARNING: subsequent failure to remove RITA        may cause further problems.     o  Religious Layer: Strike advocates of disruptive or        obstructive religions, and their vendor representatives, with        RITA, preferably on the top of the skull. In extreme cases, the        RITA may be used as a phlactory, funerary urn, or endcap for        bus-and-tag cables.5. Further Work   A RITA MIB is under development.  This may require adding interface   technology and hardware to RITA; a prototype is depicted in Figure 2.         comb      neck             body                    feet          |         |                |                       |          v         v                V                       V           ,^/'/,           ,______________________.         ,         i'  '  /          /                       =========<-        / <o>   `---------/                        \_____________m      .;__.  ,__,--------.                         /         ,         / ,/ vv          \                        =========<-        '-'                `-----------------------'         `         ^     ^                                     ^          ^         |     |                                     |          |        beak  wattles                               legs       ethernet                                 Figure 2.   There has been to date no investigation of the possible use of RITA   to implementRFC 1149.   Additionally, this tool has been used with some success for dealing   with non-network problems, particularly in the debugging of SCSI bus   malfunctions.Bressen                      Informational                      [Page 4]

RFC 2321                          RITA                      1 April 19986. Security Considerations   The RITA will only have serious impact on system security facilities   if it is filled with lead shot. It does however, increase the   personal security of system administrators; few network toughs are   willing to face down a sysadmin armed with a RITA and a confident   demeanor.7. Citations and References   [1] Postel, J., and J. Reynolds, "Instructions to RFC Authors",RFC2223, October 1997.   [2] McPhee, A.,http://www.mcphee.com   [3]http://www.clix.net/5thworld/no-osphere/3e/manteia.html   [4] Waitzman, D., "Transmission of IP Datagrams on Avian Carriers"RFC 1149, April 1990.   [5] Raymond, E. (editor), "The New Hacker's Dictionary" 2nd ed., MIT   Press, September 1993.  ISBN 0-262-18154-18. Acknowledgments   Initial Development of RITA, Editing, and excellent leather jacket   provided by Bob Antia, first reading by John "cgull" Hood,   illustrations done using equipment provided by Elizabeth Goodman and   Gerry Goodnough.9. Author's Address   Andrew K. Bressen   72 Endicott Street   Somerville, MA   Phone: 617-776-2373   EMail: bressen@leftbank.com, bressen@cohesive.com, bressen@mirror.toBressen                      Informational                      [Page 5]

RFC 2321                          RITA                      1 April 199810.  Full Copyright Statement   Copyright (C) The Internet Society (1998).  All Rights Reserved.   This document and translations of it may be copied and furnished to   others, and derivative works that comment on or otherwise explain it   or assist in its implementation may be prepared, copied, published   and distributed, in whole or in part, without restriction of any   kind, provided that the above copyright notice and this paragraph are   included on all such copies and derivative works.  However, this   document itself may not be modified in any way, such as by removing   the copyright notice or references to the Internet Society or other   Internet organizations, except as needed for the purpose of   developing Internet standards in which case the procedures for   copyrights defined in the Internet Standards process must be   followed, or as required to translate it into languages other than   English.   The limited permissions granted above are perpetual and will not be   revoked by the Internet Society or its successors or assigns.   This document and the information contained herein is provided on an   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.Bressen                      Informational                      [Page 6]