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Systemhouse Mobach bv - Networks

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Networks can hardly be missed nowadays in data processing environments. Often security, stability, reliability and scalability are areas where not enough resources are dedicated to. Perhaps because of the high costs of the recources needed. Among these resources are also education.

For the creation of networks a good knowledge of all protocols in use in all relevant protocol layers is needed Our research concentrates on Internet Protocolls, not because that might be the best protocols invented but it are the most used protocols in heterogeneous environments. Good study books in this area are :

  • TCP/IP Network Administration by Craig Hunt, O'Reilly & Associates
  • TCP/IP Illustrated volume 1, 2 en 3 by W. Richard Stevens, Addison-Wesley

Our primary focus areas are security, stability, reliability and scalability. UNIX and the Free Software operating systems OpenBSD and GNU/Linux are well suited for our purposes because of the open development model, the use of international open standards and the open discussion and repair in case of security vulnerabilities. Security problems don't disappear when you close your eyes, put your head in the sand or keeps them secret.

The fact that Free Software like OpenBSD and GNU/Linux is ported to many different platforms offers the choice of the hardware needed for a task. That offers opportunities regarding stability and scalability. As a matter of fact the differences between pc's and mainframes are still valid.

Security is not a permanent status, it's a process. In that process permanent attention must be paid to all security related areas like log analysis, monitoring, software maintenance and testing. While building secured systems and networks is a cumbersom process it's not the end but just the start of that process.

Multi Purpose Network Device.

One of the products resulting from our research is the Multi Purpose Network Device, in short the MPND. The hardware consists of at least the following components supported by GNU/Linux :

  • a motherboard with CPU, supporting components for bus management and some I/O chips,
  • RAM memory,
  • flash memory or a Disk On Chip (DOC),
  • a network adapter (NIC)
  • facilities to add an additional adapter for ethernet / ISDN / V.35 etc.
  • optional connectors for keyboard and monitor.
This description shows that it an embedded device. No hard disk, no floppy unit, no CD unit are present. The usual network environment however doesn't require a real-time operating system, so the common versions of GNU/Linux can be used.

Except for the small amount of flash memory the system described here is a plain simple general purpose computer with GNU/Linux. No wonder that the next functionalities are available :

  • routing,
  • bridging,
  • firewalling,
  • traffic shaping,
  • Network Address Translation,
  • Masquerading,
  • Transparante proxy (rinetd, uredir),
  • DNS (bind, ens),
  • and so on.
Theoretically Sendmail is also possible but we didn't test it ;-).

in case someone wants the sources of the software packages mentioned, you can have them. We don't offer ftp service because bandwidth is very expensive here. We can of course send you ens on floppy and the original SuSE Linux distribution, which contains all these sources. That is however quite expensive because of processing and shipping costs. You better get the sources from :

  Last change at 2010-12-17 by Fred Mobach <> Copyright © 2002 Fred Mobach  
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