WO1999021143A1

WO1999021143A1 - Method for security control of computer equipment and implementing system

Info

Publication number: WO1999021143A1
Application number: PCT/FR1998/002230
Authority: WO
Inventors: Pierre Mousel; Jean-Jacques Meddas; Jean-Paul Crouzillat
Original assignee: Simatel
Priority date: 1997-10-16
Filing date: 1998-10-16
Publication date: 1999-04-29
Also published as: EP1010153B1; FR2770013A1; EP1010153A1; FR2770013B1; ATE219267T1; DE69806022D1; AU9546298A

Abstract

The invention proposes to exploit the presence, in computerised distribution, of an oversized wiring termination relative to the network applicative requirements. By installing for each computer equipment to be controlled, an impedance loop on a connection left free, it is then possible to control simply and inexpensively the presence of said equipment. The method for security control of computerised equipment items (1) mounted on a pre-wiring connection system (2, 3) to computer networks consists in detecting and comparing impedance values of a line ending interface (9), installed on each element to be controlled (1), with a value located in a standard interval, then with a high reference value, higher than the standard interval, in centralising and recording data corresponding to the comparisons carried out in an adapted computerised structure (4), in displaying on ad hoc means (E) the states corresponding to the data and identifying events related to a connection, a disconnection and an intervention on each equipment to be controlled, and in triggering an adapted alarm in case of unauthorised manipulation.

Description

METHOD FOR MONITORING COMPUTER EQUIPMENT AND SYSTEM FOR IMPLEMENTING IT.

The present invention relates to the field of monitoring computer type equipment, such as terminals, in particular installed in a computer network. In parallel with the proliferation and development of computer networks (intranet, ethernet, toc in-ring etc.) which ensure the transmission of data between terminals through structured and standardized cabling systems in accordance with standards, the need to control the presence of this growing set of equipment has become clearer.

In order to combat the theft of such terminals, it has already been described, for example in US patents 4,224,483 or FR 2,649,269, monitoring methods which consist in periodically identifying the entire fleet constituting the same network. These methods require the establishment of autonomous and parallel surveillance systems. Such systems are complex and expensive because they require specific cabling, integration of an identifier in the equipment (transponders) and additional management means. In addition, network management systems do not make it possible to control the presence of computer equipment connected but not connected to the network.

In order to remedy these drawbacks, the invention proposes to exploit the presence, at the level of computer distribution, of oversized connectors in relation to the needs of the network application. Each piece of equipment indeed has plots of connection remained free, not connected to the local network adapter card to which the equipment possibly belongs. By setting up, for each computer equipment to be monitored, an impedant loop on a connection that remains free, it is then possible to control the presence of said equipment in a simple and inexpensive manner.

More specifically, the invention relates to a method for monitoring computer equipment mounted on a cabling system. This method consists in detecting and comparing impedance values of an end-of-line interface, installed on the outside of the equipment to be monitored jointly or on the inside of this equipment on the communication card, with a value located in a standard interval then at a high reference value, higher than the standard interval, to centralize and record the data corresponding to the comparisons carried out, to visualize the states corresponding to the data and identifying events relating to a connection, a disconnection and intervention on each piece of equipment to be monitored, and to trigger the appropriate alarm in the event of unauthorized handling. Advantageously, the alarm is accompanied by personalized instructions, for example relating to the type of equipment disconnected or to the local configuration.

User monitoring or maintenance inhibition for a predetermined period may be provided for mobile (portable) equipment or for any equipment. This inhibition corresponds to a planned event of disconnection or intervention on site, due to special circumstances (repair, maintenance, moving, etc.). If the disconnection is made within the time range information is then recorded as an event without triggering the alarm.

According to one embodiment, the variation in impedance of the end-of-line interface of each monitored device is detected by reference to a high impedance value, for example equal to twice the interface impedance value , taking into account its tolerance. A detected impedance value strictly greater, respectively less than or equal to this high reference value, signifies a disconnection, respectively an intervention by or on the monitored equipment.

In addition to the connection, disconnection / intervention states, authorized or not of the monitored equipment, the method of the invention according to a particular embodiment, also detects an unauthorized intervention state on line by detecting the low impedances corresponding to a setting short circuit of the line. This detection is done by studying the variations in impedance by reference to a low impedance value, for example to the interface impedance value taking into account its tolerance. The detection of this state corresponds to an unauthorized line intervention and triggers an alarm with an intervention instruction.

The records of the impedance variations of the method according to the invention allows _ traceability _, that is to say the constitution of a history of connections, disconnections and interventions carried out on the laptops and other equipment monitored.

The invention also relates to a system for implementing this method. Such a system comprises, as end-of-line interface, an impedant loop on a pair of pins available from an interface box to the computer equipment network adapter card, conventionally connected to the network by a patch cord. The presence of the loop is checked by a surveillance detector with analog / digital interface coupled to the loop using a specific patch cord, and which delivers a digital presence message by comparison with at least one value of impedance, from known logic components. These messages are processed to trigger information or alarm messages based on the messages received.

According to a particular embodiment, the surveillance detectors are grouped in central communication interface acquisition units on the network, the surveillance computer processing the information thus communicated.

In an exemplary embodiment, the presence messages are accompanied by personalized setpoint messages in the event of unauthorized disconnection, and the processor of the monitoring computer is informed of the authorized disconnections for the equipment concerned for a predetermined duration. In the latter case, the processor of the monitoring computer can record a data sequence containing the information identifying the user, identifying the equipment concerned and the duration of disconnection. The digital message of presence of this equipment, which also contains the identification sequence of the equipment, is then inhibited by a suitable subroutine of the processor for the predetermined duration.

To record the connection, disconnection and intervention states, a detection of variation in the impedance, by response to a high value, equal for example to twice the original impedance of the loop can be obtained with the surveillance detectors of the system according to the invention. In addition, an impedance of the loop lower than the original impedance value can also be detected by the monitoring detectors and recorded by the processor of the monitoring computer. This recording corresponds to a state of unauthorized intervention on the line. The processor translates these detections by displaying information concerning connection, disconnection or intervention events, by triggering alarms and / or instructions adapted to the site thus detected in the event of authorized interventions (disconnection of the equipment or intervention on the equipment or on line). Other characteristics and advantages of the invention will appear on reading the description which follows, relating to a detailed example of embodiment, accompanied by the appended figures which represent, respectively: FIG. 1, the organizational diagram of an example of monitoring system according to the invention;

FIG. 2, examples of display states of the monitor of the surveillance computer;

- Figures 3 and 4, two logical flowcharts of the main steps of two embodiments of the monitoring method according to the invention.

With reference to the organizational diagram illustrated in FIG. 1, a surveillance system according to the invention comprises: - DTE terminals (initials of Data Processing Terminal Equipment) under surveillance such as terminal I;

A pre-wired architecture comprising a terminal socket per terminal, which is an RJ 45 type socket referenced 10 or a capillary module of distribution 2 (for at least two terminals) connected to the terminal by a bus; for example an Ethernet bus 8, of type 10 base T is used in the case of the monitoring computer 4 of the monitoring system (see below) and of the monitored DTE terminal 1;

- a local area network (LAN) architecture, comprising link rings 3 between floor distributors (not shown) coupled to resource modules of the network application 6, coupled on the one hand to the capillary modules 2 and to the terminals 1 and, on the other hand, to the hub nodes 7 of the network architecture; each terminal can be connected to the network by connection of an internal network adapter card (for example Ethernet 10 Base T), of an interface box, all connected to a patch cord K of the network application;

- an architecture of the surveillance system according to the invention, using an impedant loop B on a pair of available pads P _j P ₂ in the security interface box set up for each terminal under surveillance 1 (see enlarged part PA in the figure 1); loop B is an end-of-line interface provided with a contact M for uncoupling the interface box and the equipment to be monitored; it is connected via a patch cord K 'to an analog / digital monitoring detector 11 via a capillary module 2; these detectors 11 are grouped into groups of 31 in central acquisition units 12; these units transmit information to a surveillance computer 4 via a communication bus 13 to a communication interface 14, an RS 485 / RS 232 in the example of embodiment, via a ring road 3 and its capillary module 2. This PA security interface box includes a connector K, K 'of the RJ45 type, of which four terminals K are connected to the network and of which two other terminals K' P ^, P ₂ make the loop B. The interface box can be made at inside or outside of the equipment to be monitored.

In operation, the surveillance computer 4 displays on a monitor E the states of the terminals under surveillance. The computer processor manages a monitoring algorithm whose execution in computer form is within the reach of those skilled in the art to translate the information provided by the central acquisition units by a clear message which appears on the monitor E, and which relates to the connection, disconnection or intervention states relating to each terminal under surveillance. The algorithm contains an inhibition soubroutine in order to discriminate disconnections and authorized interventions from unauthorized actions. Each detection interface 11 performs a dual function: a state change input function, - presence, opening or short-circuit of the loop -, and a communication function to its central acquisition unit 12 with acknowledgment of this communication.

The monitoring processor acknowledges each central unit 12 of the messages received, the units then acknowledging the monitoring interfaces concerned of the reception of these messages. Examples of displaying states I to VI of each monitored item of equipment are shown in FIG. 2. States I, II and V refer to events corresponding, respectively, to connection, disconnection and intervention information authorized. . States III, IV and VI refer to alarms corresponding, respectively, to disconnections, interventions on line or on equipment, not authorized. The additional information provided (outlet, office, geographic location, technical room and user) is the same in the case of events or alarms. The alarms trigger specific instructions on the nature of the identified violation (intervention on line or on equipment, disconnection) and on the geographical location of the equipment concerned.

More precisely, when an infraction is carried out, the detector detects this event and the interface translates it by a digital alarm message transmitted to the processor of the surveillance computer 4 by the acquisition unit concerned. This event thus causes an alarm rise corresponding to states III, IV or VI by indicating the configuration adopted by the client user of the network or of the equipment in question. In the case where the disconnection is authorized by information pre-recorded in the processor, the alarm reporting by the central processing unit concerned is inhibited for this connection for a predetermined period of time, and the event is announced as such on the monitor. In the exemplary embodiment, the prerecorded information consists of a data sequence containing

- information identifying the user, the equipment concerned and the planned operation (moving, repair, maintenance, changing cards, etc.) in the form of passwords,

- as well as the duration of disconnection.

The digital message of presence of this equipment transmitted by the central unit concerned, which also contains the sequence of identification of the equipment, is then inhibited by the monitoring algorithm for the predetermined time.

In FIG. 3, the main steps of a first embodiment of the monitoring method according to the invention are illustrated in the form of a logical flow diagram for processing the data of the monitoring architecture by the managed monitoring algorithm by the monitoring computer. These impedance variation data of the end-of-line interface are supplied by the monitoring interface of each device monitored, a monitoring interface being for example based on the detection of the monitoring detector described above. These data are processed with reference to critical impedance values, in order to classify the variations of the detected impedances, according to predetermined states of the equipment concerned: connection, disconnection and intervention, and according to pre-entered authorization data. The data from the monitoring interface is first compared to a standard value at the first logic state 21. The presence of the connection of the monitored equipment is reflected by an impedance value from the end of line interface IB in the range R +/- T (%), R being the standard value and T (%) being equal to its relative tolerance (compared to the value of R). For example, for an impedant loop such as loop 9, R is equal to 1 kW and T (%) is 10%. The display 22 of the surveillance monitor then corresponds to the connection state I (FIG. 2). When a variation in impedance is measured by the monitoring interface according to the recording 23, a logic comparison terminal 24 controls the classification of the states of authorized disconnection II and of unauthorized disconnection III (FIG. 2). In In the example of embodiment, the variation is composed at values greater than 2R + T (%) (states II and III) at terminal 24, at values of the interval 2R + T (%).

If the measured impedance I B is less than 2R + T (%) (in%), the state of the equipment monitored is a state of intervention on the site. Depending on the existence or absence of a maintenance inhibition command 32 entered via the local network (abbreviated to LAN), the intervention recorded is respectively of authorized or unauthorized type, corresponding to the states V and VI (FIG. 2) viewed respectively at 33 and 34 by the monitor of the surveillance computer.

In the case of an unauthorized intervention, the instructions set are displayed and the local and general alarms triggered at 35. If the measured impedance is greater than 2R + T (%), the state of the equipment monitored is a disconnection state. Depending on the existence or absence of an inhibition command originating from the LAN and supplied by the user of the monitored equipment or of the computer maintenance, the disconnection is respectively of authorized or unauthorized type, corresponding to states II and III (figure 2) displayed in 26 and 27. In the case of an unauthorized disconnection, the setpoints are displayed and the local and general alarms are triggered in 28, as predefined by the manager.

According to a particular embodiment illustrated in FIG. 4 of the method illustrated in FIG. 3, an additional logic comparison terminal 29 makes it possible to define an unauthorized intervention state on the line (state IV of FIG. 2). When the impedance IB is less than 2R + T%, the data is compared with R - T (%) at terminal 29. If then the impedance IB is greater than R - T (%), the intervention states V and VI are detected in accordance with FIG. 3. An impedance IB is less than R - T (%) is indicative of a short circuit operated on the equipment . The corresponding state is state IV of unauthorized line intervention (Figure 2).

Such a state is displayed at 30 on the flow diagram of FIG. 4, and triggers the local and general setpoints and alarms adapted at 31. In all cases of display of states II to VI, a return to a state of start 20, of the unconnected link type and corresponding to an impedance of infinite value for the end-of-line interface loops the flow diagram represented. Such a return is in fact followed by the interrogation step on the connection state I.

The invention is not limited to the examples described and shown. It is for example possible to distribute the data coming from the central acquisition units or the surveillance detectors on different processors and / or on different display monitors as a function of the location of the monitored equipment, for example on equipment located close to '' disconnected equipment, in order to obtain local information and thus allow more effective intervention. Furthermore, high or lower impedance reference values may vary depending on the architectures concerned. The invention has been described using an impedance loop B which has two impedances 1- _^ and I ₂ ; however, the invention can be implemented with a loop in which the impedance I-_ is replaced by an active electronic circuit which produces for example an electronic identification label with a code. When the contact M is closed (interface box removed), the electronic circuit is short-circuited, which is detected by the central acquisition unit 12 via the surveillance detector 11. When the contact M is open (interface box not removed), the electronic circuit transmits on the pads P ₁ and P ₂ , the serial code to the central acquisition unit 12 in the form of variations in impedance, which makes it possible to identify the box. When the link 8 is cut, the central acquisition unit 12 detects an impedance of infinite value, which is interpreted as a disconnection of the equipment with respect to the network.

This electronic tag can be inhibited by the central acquisition unit 12 during an authorized disconnection so as not to be detected by monitoring equipment capable of reading these tags.

Claims

1. A method of monitoring computer equipment (1) mounted on a prewiring system (2, 3) for connection to computer networks, characterized in that it consists in detecting and comparing impedance values of an interface end of line (9), installed on each piece of equipment to be monitored, at a value located in a standard interval, then at a high reference value, greater than the standard interval, to centralize and record the data corresponding to the comparisons carried out, to view the states corresponding to the data and identifying events relating to a connection, disconnection and intervention on each device to be monitored, and to trigger the appropriate alarm in the event of unauthorized manipulation.

2. Method according to claim 1, characterized in that a monitoring inhibition command for a predetermined period is provided for mobile equipment and any equipment on which authorized manipulation is carried out, the disconnection information then being detected, centralized and recorded as an event without triggering an alarm.

3. Method according to claim I or 2, characterized in that the data for comparison with the high impedance value is coupled to the inhibition command when the impedance value of the end of line interface is, respectively , higher or lower than the high reference value, identifying the disconnection states (II, III) authorized or not authorized, respectively intervention states (V, VI) authorized or not authorized.

4. Method according to one of the preceding claims, characterized in that a state unauthorized intervention on line (IV) is identified when the impedance value of the end-of-line interface, compared to a lower reference value, after being detected as lower than the high reference value, is detected as lower than this lower reference value.

5. Monitoring system for implementing the method according to any one of claims 1 to 3, characterized in that it comprises, at the output of each piece of equipment to be monitored (1) equipped with a pre-wired capillary module ( 2), at least one free pin (PI-P2) for connection to this module, in which is arranged an impedant loop (9) whose presence is verified by a surveillance detector with analog / digital interface (11) which compares the impedance value of the loop (9) at the standard interval and at the high value, and which delivers a digital message processed by the processor of a monitoring computer (4) for viewing screens (22, 26, 27 , 33, 34), corresponding to connection, disconnection and intervention states on the equipment, authorized or not according to inhibition command entries originating from the network and centralized by the monitoring computer (4), and to trigger messages from alarm based on messages received.

6. System for implementing the method according to claim 4 characterized in that, in addition, the monitoring detector (11) compares the impedance value of the loop (9) with the lower reference value when this value d impedance is detected at a value lower than the high reference value to display (30) a short-circuit state (IV).

7. System according to claims 5 or 6, characterized in that the high reference value is equal to twice the standard value at least one standard interval and the lower reference value is equal to the lower value of the standard interval.

8. System according to claim 7, characterized in that the detection interfaces (11) are grouped within central acquisition units (12) which are coupled to the surveillance computer (4), each detection interface (11) providing a function for entering changes in the state of the loop and a communication function to its central acquisition unit (12).

9. System according to one of claims 7 or 8, characterized in that the processor of the monitoring computer (4) is informed of the authorized disconnections for the equipment concerned for a predetermined period by recording a sequence of data containing user identification information, identification of the equipment concerned and the duration of disconnection, the digital message of the presence of this equipment, which also contains the equipment identification sequence, then being inhibited by a suitable subroutine of the processor for the predetermined duration.

10. Monitoring system according to any one of claims 7 to 9, characterized in that the data coming from the central acquisition units (12) are distributed on different processors and / or on different display monitors depending on the location monitored equipment.

11. terminal monitoring system (1) according to claim 10, comprising

- a pre-wired architecture having a capillary module (2) per terminal, distribution bypasses (3) and at least two free wiring pins (10 ') of the capillary module of a monitoring computer (4),

A network application architecture coupled to the capillary modules (2) of the terminals (1) via the ring roads (3), and

- a surveillance architecture using the electric loop (9) on each free socket (10) of the pins of the capillary modules (2) of the terminals (1) under surveillance, each capillary module being connected to a surveillance detector with analog / digital interface (11), the central acquisition units (12) which group together the detectors (it) transmit information to the surveillance computer (4) via a bus (13) to a communication interface (14).

12. System according to any one of the preceding claims 5 to 11, characterized in that the impedant loop (9) comprises two impedances (II, 12) of determined values.

13. System according to any one of the preceding claims 5 to 11, characterized in that the impedant loop (9) comprises an active electronic circuit which produces an electronic identification label comprising a code which is detected by the surveillance detector ( 11) when contact M is open.