Technical evaluation—TS300 terminal security device

Technical evaluation—TS300 terminal security device

Vol. 10, No. 9, Page 4 departmental networks. BIS Applied Systems Ltd was contracted to review network suppliers’ of reported incidents involving d...

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10, No. 9, Page 4

departmental networks. BIS Applied Systems Ltd was contracted to review network suppliers’

of reported incidents involving damage to files, sabotage and unauthorized data interception.”

security proposals and to advise on policy and implementation. As part of this, BIS has produced guidelines for departments’ use of the GDN. Departments wil be able to add on

In all, it accounted dollar losses.

additional security measures, such as encryption, for particularfy sensitive applications. The GDN will use Open Systems lnterconection Standards and the X.25 protocol. Opposition Members of Parliament are worried that if anyone is given access to all the files on the network, they will be able to call up unprecedented amounts of data about an individual person. Mr Eric Howe, the UK Data Protection Registrar, wants the Government Departments involved to make it clear under what condition personal data might be exchanged over the network. The concern is that once a network of this size is set up, the potential is there to exchange information. There are also fears about the possible breaches of privacy or damage which could take place if unauthorfzed users break into the network. As we reported in the June 1988 issue of CFSB, UK Members of Parliament have published a report warning that Government departments need to do more to fight computer crime.

for no more than 0.1% of

The Bureau was also critical of the media’s treatment of computer ‘viruses’. This coverage, it said, had an hysterical tone induced by the writers’ ignorance of what they were attempting to describe. Among the main perpetrators of computer fraud were programmers; management was responsible for about 2% of computer abuse but the financial loss was disproportionately serious, accounting for some 37%. Frank Rees, Melbourne Australia

TECHNICAL EVALUATION - TS300 TERMINAL SECURITY DEVICE Developer, manufacturer and vendor:- Time and Data Systems International Ltd, Crestworth House, Sterte Avenue, Poole, Dorset BH15 2AL, UK; tel: 0202-666222. Availability:Any RS-232 line from a termainal or computer operating at speeds of up to 9600 bps.

INCREASE IN AUSTRALIAN COMPUTER ABUSE According to a report by the Melbournebased Computer Abuse Research Bureau, there has been a marked increase in computer abuse in Australia. The Bureau has identified more than A$1 million losses through computer abuse in the first quarter of this year. This compares with an average of A$1 million per year over the last decade. Over 60% of the losses were due to computer fraud, and the Bureau identified theft of equipment as another growing source of concern. In contrast, hacking is an over-dramatized form of computer abuse, attracting a greatly disproportionate amount of publicity in the Australian media. The report notes: “The number of reported cases of abuse from hackers has remained low, as has the number

COMPUTER FRAUD 81 SECURITY BULLETIN

Cost:- Well under f500 per unit depending on volume and the cabling involved. Badges are under f2.00 each (in quantity). A perennial problem in computer security is to constrain the availability of computer facilities to those people who are authorized to have access to the computer in question. This problem is so all-pervading within the computer industry that a survey of the currently available ‘solutions’ would expand to fill a complete book. This month’s technical evaluation is about just such a product. Many (most?) remote computer systems are ultimately accessed via RS-232 lines. By this I mean that no matter what method is used to connect to a remote computer (dial-up line, leased line, permanent connection etc.), there is a good chance that the final connection to the terminal, or computer with terminal emulation

0 1988 Elsevier Science Publishers Ltd., England. /88/$0.00 + 2.20 No part of this publication may be reproduced, stored in a retrieval system, or transmitted by any form or by any means, electronic, mechanical, photocopying. recording or otherwise, without the prior permission of the publishers (Readers in the U.S.A.-please see special regulations listed on back cover.]

Vol. 10, No. 9, Page 5 software, will be an RS-232 line. 25way D-type connectors appear on many different types of equipment as evidence of this. The TS300 terminal security device discussed in this article is installed in such a communications line. Its function is to prevent communications between the terminal and the host computer unless the user has correctly proved his identity. This is done by inserting a badge (called a Microcard, see later) into the card reader on the TS300. The Microcard must remain within the TS300 for the RS-232 line to remain active. Each TS300 comprises a slim box designed to sit underneath a terminal. Apart from artwork there is nothing visible on the front panel of the TS300 except a slot into which the Microcard is inserted, and a small LED next to the slot which is used as an indicator. Each Microcard has the same dimensions as a credit card, but there is no magnetic stripe attached. Although it looks black, a Microcard is transparent to infra-red light. Up to 64 bits of information can be encoded on the card in a form rather like the bar-codes used by modern supermarket check-outs. The coding method used is proprietary. Whenever a Microcard is inserted into the slot on the front panel, this information is read from the Microcard, and verified against information stored on battery-backed RAM within the TS300. The security manager can decide which users are allowed to use each particular TS300. He programs the TS300 by means of a set of ‘Mastercards’, whose special significance is recognized by the TS300. This has the useful consequence that the front panel of the TS300 is not cluttered by a keypad and display. Users should find it fairly intuitive to use. After all, faced with owning a card, and a slot on a box in front of you, what else can you do apart from putting the card in the slot? If the TS300 does not accept a user, a normally open 5pole relay within the TS300 prevents data passing through. For the technically-minded, this relay disconnects TX, RX, RTS, CTS and DTR, thus effectively preventing data transmission. Users cannot remove the cables to the TS300 as they are terminated inside the case.

COMPUTER FRAUD & SECURITY BULLETIN

The case of the TS300 is tamper-resistant to the extent that if an attempt is made to open it, all information held within the internal battery-backed RAM is erased. Unless this alarm is triggered, the contents of the battery-backed RAM are preserved for up to one month when power is not applied, and indefinitely while power is applied. Although I have no space to go into detail within this short article, the TS300 has two main modes of operation - hardware mode and software mode. In hardware mode, a remote TS300 does the user verification for itself, and does not communicate with the host. In software mode, the host computer can carry out a dialogue with the TS300. There is a challenge and response facility (to help circumvent the cables being bypassed), and an audit log can be generated at the host. The extra facilities offered by the software mode need software on the host computer to operate. Such software is inevitably specific to the particular host computer. The security manager can therefore decide for himself which mode to use, the simple-to-install but easier-to-circumvent hardware mode, or the better controls offered by the software mode. The Microcards supplied with a TS300 are crucial to the security provided by the TS300. When cards are made, unique IDS are assigned to each card by the manufacturer, and permanently but invisibly added to each Microcard. Any desired artwork, photographs, and signatures can be added to the card before lamination. I can personally confirm that the manufacturers are well equipped to produce logos and artwork. Conclusions The TS300 is essentially an intelligent security switch. A user is only allowed access to computers via the RS-232 line connected through the TS300 if he possesses the correct badge (Microcard) to persuade the TS300 that he genuinely should be using the terminal. The Microcards seem to be more difficult to forge than credit cards (which can be easily copied given a card read/write mechanism), and are very cheap to purchase (see above).

a 1988 Elsevier Science Publishers Ltd., England. /88/$0.00 + 2.20 No part of this publication may be reproduced, stored in a retrieval system, or transmitted by any form or by any means, electronic, mechanical, photocopying, recording or otherwise. without the prior permission of the publishers. (Readers in the U.S.A. - please see special regulations listed on back cover.)

Vol. 10, No. 9, Page 6 Each TS300 comes with a comprehensive 48-page manual which explains both the hardware and software very clearly. It suffers from not having an index, so you have to dig around to find a particular topic. While learning about the TS300 for this article, I was shown around the factory, and was impressed by the manufacturing facilities (which are approved to BS5750 Parts 1,2 and 3). In summary, the TS300 works well, is well made, and offers good value for the price charged. If anyone were making a determined attack on a system secured by the TS300, then it has to be accepted that the attack could succeed. The cables could be bypassed unless the challenge and response software is running on the host computer. Without the protection offered by an encryption algorithm, an intruder’s hardware could pose as a TS300, and the TS300 could simply be removed. I could go on. Having said all this, I accept that these attacks need specialist knowledge, the manufacturers make no extravagant claims for the benefits that installation of a TS300 can offer, and, assuming that the environment you are trying to protect does not require the highest levels of security, you could do worse.

processes. The Australian inverter loses only about 2 to 3%. Its inventor, Mr John Piechnick, has worked in the radio section of Australia’s Royal Flying Doctor Service, specializing in power storage systems for pedal radios and, similarly, with survey and mining equipment in Australia’s remote areas. It was the problems power surges caused him in this work which provided the spur to Mr Piechnick’s invention. In a recent demonstration he used a reflex inverter to produce a constant supply of electricity to a sensitive computer while a heavy air-conditioner and arc welding equipment were switched on. The director of the Adelaide Innovation Centre in South Australia, Mr John Taylor, said the system has applications wherever equipment depended on a reliable and uninterruptable supply of electrical current. A company, Power Reflex Proprietary Ltd, has been established to make and market the inverter. Its chairman, Mr David Zundel, said one of the A$60 000 devices had already been installed at the headquarters of the Flinders Ranges National Park in South Australia. Frank Rees Melbourne Australia

Keith Jackson

AUSTRALIAN INVENTION PROTECTS COMPUTERS FROM POWER SURGES At the flick of a switch an Australianinvented reflex inverter guarantees a steady flow of electrical current and protects computers from power surges. The computer-controlled device is a reservoir for electrical energy, which it can absorb from power mains or generators and release at a required steady voltage. This protects the computer from the serious damage that can result from power surges. The trouble with other inverters on the international market is that they lose about 15% of power during the storage and inversion

COMPUTER FRAUD & SECURITY BULLETIN

PHYSICAL SECURITY - THE KEY TO PROTECTING COMPUTER SYSTEMS On Monday 23 May 1988 the Six o’Clock TV News from the British Broadcasting Company was interrupted by women protesting at proposed new laws affecting lesbians. They had bypassed the building security with the greatest of ease. According to their spokeswoman, they had cased the Television Centre about a month previously and “couldn’t believe how easy it was to get in”. At that time the spokeswoman had attached herself to a party of visitors and had then separated from the group and “wandered around until she discovered the sixth floor TV studio”. On her return visit, she simply told the receptionist they had come to see someone

0 1988 Elsevier Science Publishers Ltd., England. /tW$O.OO + 2.20 No part of this publication may be reproduced, stored in a retrieval system, or transmitted by any form or by any means. electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the publishers. (Readers in the U.S.A. -please see special regulations listed on back cover.)