S 2.234 The design of Internet PCs

Initiation responsibility: IT Security Officer, Head of IT

Implementation responsibility: Head of IT, IT Security Officer

After having made the decision to provide one or several Internet PCs for the utilisation of Internet offers and services, a concept regarding the specific implementation should be drawn up. This concept should define the functional requirements, security requirements, required regulations, competences, as well as specifications regarding the technical implementation and utilisation.

It is recommendable to at least take into consideration the following sub-aspects when drawing up the concept. Depending on the present general organisational conditions, it may be required to add further items to the concept. Information regarding this can be found in the modules S 3.1 Security gateway (firewall) and S 5.4 Web server.

Functional requirements

At first, it should be defined which services offered on the Internet are to be used, e.g. World Wide Web (WWW), email, news, or instant messaging. This has substantial effects on the software to be installed and the required security safeguards.

In order to be able to select an appropriate Internet service provider (ISP) and expedient connection technology, the required bandwidths and response times should also be defined for the individual Internet services.

In order to obtain criteria for the installation sites of the Internet PCs, the concept should then document the extent of the expected user traffic and the requirements present with regard to the spatial proximity of the Internet PC to the employee.

Moreover, it should be defined how data from the Internet, e.g. downloaded files, is to be handled and whether this data may be processed further on other systems or has to be archived, for example. Data exchange between Internet PC and local network requires additional security safeguards and regulations.

Security requirements

Regarding the security requirements, the concept should define whether the information retrieved from the Internet or sent to other computers on the Internet must be protected against unauthorised reading or unauthorised modification.

Moreover, the concept must document whether data worthy of protection must be stored for longer periods of time to the Internet PC. This is particularly relevant if the Internet PC is also used for email services.

Regarding the accountability and the protection against unauthorised use, it should be defined whether users must authenticate on the Internet PC before they are allowed to use the Internet access.

The application concept should also include statements regarding the availability requirements. Therefore, it must be defined whether a longer failure of the Internet PC is tolerable or whether alternative solutions must be established for this case.

Required regulations

Regarding the utilisation of the Internet PC, existing regulations must be adapted or re-defined. This also particularly includes the security concept and the user guidelines (see also S 2.235 Guidelines for the use of Internet PCs). However, depending on the location, the use of an Internet PC may also have effects on existing site access regulations, for example.

Competences

Internet PCs also need to be administered and maintained by trained personnel. Therefore, the application concept should define which employees and/or roles are responsible for administrating and operating the Internet PC and who must be notified in the event of a failure of the Internet PC or if signs of a security incident are detected.

Since the usage profile and the application environment of Internet PCs may change quickly, the concept must be updated. The corresponding responsibilities should be documented.

Specifications regarding the technical implementation (hardware)

The concept should define how many Internet PCs are used and whether these are to be networked with each other and equipped with a joint Internet connection. In this case, the components to be used for networking should also be defined.

Moreover, the hardware equipment of the Internet PCs should be defined. For example, this includes the hardware platform, drives, interfaces, and peripheral devices.

If data backup is required for the Internet PC, the concept should define the media or interfaces used to this end.

Specifications regarding the technical implementation (software)

In order to make administration easier, all Internet PCs should be equipped as identically as possible. Therefore, the software equipment should be defined as much as possible in the concept.

The operating system used should be defined in the application concept in any case. If user authentication is required, only operating systems with effective user separation should be used, e.g. Windows NT/2000 or Linux. Windows 9x/ME are inappropriate in this case.

Moreover, it should be documented which client programs are to be used for the Internet services. In many cases, at least a WWW browser and an email client are required. Further examples include news clients and instant messaging programs.

In order to be able to meet the security requirements, additional security tools often need to be installed, e.g. in order to provide protection against computer viruses, for data backup, or for encryption. The concept should define the products which may be used to this end.

Specifications regarding the technical implementation (Internet connection)

The application concept should include detailed specifications regarding the technical implementation of the Internet connection in order to be able to meet the requirements for the bandwidth, response times, and availability (see also S 5.92 Secure connection to the Internet of Internet PCs). On the one hand, this includes the question as to which Internet service provider (ISP) is to be used for Internet connection (see also S 2.176 Selection of a suitable Internet service provider).

On the other hand, the access technology, e.g. ISDN or DSL, to be used for the Internet connection and the interface of the Internet PC, e.g. ISDN card or network card, to be used for this must also be defined. Depending on the access technology used, specific programs or hardware components may be necessary, e.g. DSL modem and/or router.

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