The Fixed Networks Group (FNG) at the LKN deals with a large variety of topics, alltogether aiming at

Multiperiod Planning for Optical Networks:Planning optical networks in advance is a necessity in order to provide cost efficiency. In multiperiod planning also the operation time horizon of a network is taken into account. Especially for long term operated networks, like core networks, during the operation time several planning parameters can change: Equipment costs decrease, demand requests change and technology develops. These uncertainties are taken into account by various multiperiod planning approaches in order to obtain not only cost efficient but also flexible and robust network solutions.

Next Generation automotive IT-Architectures: Complexity of vehicular information- and communication systems rises more and more in the past years. In modern luxury cars, over 80 control units connected with 10 and more sub-networks must work together to enable actual driving assistance and comfort functions. We do research on new networking technologies for cost optimization and complexity reduction, adapted from commercial of-the-shelf products. Besides medium access, packet scheduling and network management, also node positioning and cabling are considered.

Future Internet: The BMBF funded G-Lab project aims at developing architectures for the future internet. More specific, different concepts of layering and clustering of functions should be researched. Because of the increasing number of devices and their mobility new addressing and routing schemes have to be developed. The new architecture shall be capable of heterogeneous networks from wireless connections with less bitrates to fiber connections with extreme high bitrates. Furthermore, the interaction and composition of different network services into a global service oriented architecture shall be researched.

Network Management for Carrier Grade Ethernet: Today network operators update their network configuration with manual parameter tuning. A single configuration task-installing/reconfiguring a system, or provisioning a service-typically involves a large number of activities fragmented among multiple network elements. A change may cause configuration inconsistencies resulting in failures or inefficiencies and undoing changes to recover an operational state is often very difficult. Hence, an autonomic management architecture should be developed which is able to detect and correct network failures and which can reduce the manual configuration tasks.

Peer-to-Peer (P2P) Networking: A completely decentralized and self-organizing system -- as opposed to the traditional Client-Server paradigm that can be found in today's Internet. P2P networks provide a high scalability and reliability as the network lacks a single point of failure. Besides, they are able to utilize existing resources which would lie idle otherwise. But we also find new challenges and research areas when engineering P2P-based applications, e.g. to ensure system security, provide quality of service or introduce network management features.

Fault location in optical networks: The impact of a single failure in optical networks is enormous due to the huge amount of information which can be transmitted though optical fiber. Hence, fast and efficient fault location is required and even in more complex scenarios where alarms may be missing, alarms may be irrelevant or more than one simultaneous failure may occur. We propose an algorithm able to cope with this complex scenario. The impact of reliability on the efficiency of this algorithm is being evaluated.

Techno-economic studies: The competitive environment in the telecommunications sector, the difficult worldwide economical situation, the fast technological development and the new service and network requirements have pushed techno-economic studies to be one of the most important decision factors for all the telecommunication players. The Total Cost Ownership (TCO) has to be reduced by decreasing both, OpEx and CapEx, as much as possible. First, the network processes such as network installation and maintenance have to be modeled in detail so that the cost key factors are identified and the sensitivity of some parameters is evaluated. A TCO tool is being implemented so that the cost assessment of the processes can be done.