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:

• 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.
• Networks where a hub is located adjacent to a monitor that emits disruptive RF when displaying certain graphics.
• 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.
• Networks where gateways are data-sensitive
• 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.

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.