This work presents the integration of Ethernet over ATM. The main topics are:1. Setting up an environment consisting of an ATM Switch and 3 PCs equipped with net-work interface cards. The cards are driven with both, LAN Emulation (LANE) and Clas-sical IP over ATM (CLIP) using Windows95 and Linux as operating systems.2. Carrying out performance tests.3. Writing a documentation about LANE to be used in education and handed over to future students.

LANE enables LANs to communicate on Layer 2 of the ISO/OSI reference model, the media access control (MAC), over ATM-networks. Despite of the star-wired ATM network all char-acteristics of a shared media will remain. This can be achieved by several servers in the ATM-switches.CLIP allows IP-applications to use ATM networks in providing them an IP-interface. How-ever this method does not provide broadcast services, what is typical for shared media LANs. Therefore address resolution is provided by a ATMARP-sever.

At the beginning we had to solve some installation problems with the ATM network interface cards and the ATM-switch software. Finally we could make work LANE and CLIP in an Windows 95 environment. All measurement were taken with the performance measuring tool TTCPW and an ATM-Analyser. The measurements showed us the effect of different buffer-sizes and maximum transmission unit (MTU) on the performance. The results are discussed in the work.

The next step was the implementation of the ATM-network interface card with Linux. The published kernel did not function properly. The cause for the malfunctioning during the sig-nalling process lies in an disturbed signalling channel. We could measure the initialisation process of the signalling channel and clearly determine the causes for the sudden interrup-tions.

The Internet industry belongs to the fastest moving, shortest living and most future-oriented industries of our times. This circumstance sets the Internet service providers under severe pressure. In order to keep up with the speed of development they have to implement auto-mation mechanisms. Based on this situation the idea for a system was born which enables larger providers and their customers to configure Internet services through the Internet in a heterogeneous server environment.

The type of problem covered by our final project was to integrate previous semester projects into a single system. The main goal was to realise a prototype which automatically processes the customers Internet needs into configurations for DNS, WWW and email servers.

During our previous semester project we had analysed and specified the basic system behaviour, which had to be revised for this project. Furthermore the subsystems had to be redesigned.Due to the high complexity and extent of the whole system several different technologies had to be applied, like LDAP, RMI, ODBC or the Windows-Registry to name a few of them.

During the final project our attention was mainly directed to a clean, high level object-oriented design and to take into account the latest software design methods, like Booch and design patterns. Therefore the analysis and design phase took place against the background of fully object-oriented development. Thanks to the resulting superior model and our in-depth knowledge of Java programming the system could be implemented efficiently within a short period of time and as a result more than 56.000 lines of code have been written.

Several clients for service administration, a server that stores the configuration into a database and agents which configure the Internet servers have been implemented.

Thanks to strong commitment the objective of the final project has been fully achieved.

This final project came into live as part of the "the blue carrier" project. "tbc", an integrated software solution for Internet Service Providers is ment to be an advanced system for customer administration. The idea is to cut down the cost for administrating the ISP's customer accounts. With the "tbc" software the customers can completely administrate their Websites themselves which saves the ISP a lot of time and reduces confusion resulting from communication problems. All this together makes it an advanced and reliable system and even frees the customers from the tiring helplines.

Customers, of course, have to pay a fee for the requested services. Therefore a flexible billing solution is needed. A system that automatically processes charging requests through the Internet.

Today charging through the Internet is only possible with credit cards. Therefore a system is needed that checks the creditworthiness of credit cards in realtime as soon as a customer intends to buy services from the "tbc". The credit card companies have agreed on a unified system called CAR (Credit Card Authorising Request system) which exactly handles this. The communication between dealers (ISP's) and the CAR is based on the ISDN-technology. This way it is possible to grant customers access to the services immediately.

Knowing that a credit card is creditworthy is definitely not enough. There must be a possibility to charge the credit cards, as well. For this the credit card companies have agreed on a second system called CDS (Credit card Data Submission system). This system allows every dealer which accepts credit cards to submit a collection of charging records to every credit card company on a periodically basis.

This work is a part of the project "Access server". This server must be able to keep running several telephone lines at the same time. Beside it is desirable that both analog, as well as digital connections are possible. A ISDN board, which accesses the software interface CA-PI, makes only zwo telephone lines available per board. Furtermore ports and IRQs of a PC are limited so that the amount of telephone lines are fast at boundaries. Natural Micro Sy-stems (NMS) offers boards for running in a PC, which make up to 80 analog lines availa-ble, as well as ISDN, E1, T1 and much more. The application of this hardware is thus ob-vious.

My work consisted now of checking exactly the hard- and software of NMS and documen-ting my realizations. I wrote different demo programs, so that the application of the diffe-rent services and their power became clearly.

In addition a middleware EasyCTI should be developed so that the two sides (CAPI and NMS) get a uniform interface. The target was that if you want to develop an application you shouldn't take any more consideration for the underlying hardware (CAPI or NMS based), because the distinction is now made below the application layer. The possibility to establish a telephone connection via CAPI over ISDN is further desirable, since this soluti-on is by far cheaper if only a few telephone lines are necessary, as if one would use NMS systems.

Tunnelling in the access area is a very current topic. Today Internet is an economical medium to transfer data across the world. It is not only used for email but also for business purposes. As the Internet is a very unsafe area with absolutely no security mechanism, it is an easy game for spies whether it concerns home banking or industrial contracts.Our dissertation is heading exactly in this direction. It is our task to connect a LAN via a local internet provider to a service provider anywhere in the world. To avoid data espionage during the transfer, all data packets need to be encrypted. Every packet that reaches the router in the customer LAN is encrypted and then sent to its destination - the service provider - where a second router decrypts the packet and forwards it to its final destination within the local network. Obviously the two routers must use the same key.Because there are usually no global IP addresses in a company LAN, the router also has to translate these into globally unique addresses. This also offers the possibility to have more hosts in a LAN than IP addresses assigned to by your ISP. A global IP-address will be assigned dynamically by the Network Address Translation whenever a host tries to open a connection to the internet. In addition to modifying the IP address, NAT must recalculate the IP checksum and the TCP checksum.With our software, the Internet Provider can be anywhere of the world.

Gateways interconnect networks (e.g. the public telephone network with the internal H.323 network). Associated with it is a Gatekeeper which says how connections are established. Therefore it uses a database which contains the desired connection properties.

The connection properties are stored on different database systems, depending upon infrastructure already existing. The universal data base binding makes it possible to access and query different databases over a "standardised" interface. As user database I used the MS Exchange server and as customer database I used MS Access.

In a company different licenses can be assigned (user A may receive fax, user B requires a call to be forwarded on its Natel, etc.). These licenses have to be checked before a connection is established. Such a license check is performed by using the universal database binding.

The project IMAP-4-VOICE is part of the overall project "Access Server" which implements internet- and telecommunication services.In the subproject IMAP_4_VOICE an answering machine has been developed, which makes it possible for a user to access messages stored on the mail server. E-mails can be read out to the user. E-mails with a voice-attachment can be played back directly. In case of an e-mail with a fax-attachment, the input information and the sender can be queried.Within the areas mailserver-access over IMAP and Text-to-Speech we had neither a previous project nor knowledge from lessons which we could build up. Concerning communication over ISDN, a module was available to us.To the user a menu had to be supplied, which reacts on inputs of the telephone keyboard. Out of that, the necessity for a control module, with sophisticated internal structure resulted.The implementation of the IMAP protocol took several efforts because additionally the topic of communication over TCP/IP had to be compiled.The handling of the text-to-speech-engine of Microsoft, and the conversion of the output data represented a large challenge.We set ourselves the ambitious target, to develop the IMAP-4-VOICE-project in such a way that it can several users at the same time, and so we were confronted with the problems of parallel processes.Our work succeeded partly only toward the end of the available time. Finally we've succeeded to develop a program which makes the required services available to one user. Just the demo-version does not run stable jet.In our work we were confronted with different up-to-date technologies. The interaction of several future-pointing technologies made the diploma-work to an exciting project.