Learn More
This paper focuses on the traffic composition in a real GPRS/UMTS network. We present results from two datasets covering two one-week measurement periods, in December 2004 and November 2005. We show how users and traffic split between access technologies (GPRS and UMTS) and services, and present an analysis of the per-user activity at the PDP-context level.(More)
In this paper we present some observations about TCP RTT as captured in the live traffic of an operational GPRS/UMTS network. RTT samples are extracted from traces collected by passive monitoring the Gn interfaces of one of the major providers in Austria, EU. We compare results for GPRS and UMTS, and expose some methodological issues involved in performing(More)
—In this paper we present a road traffic estimation system built on top of the cellular network infrastructure. Based on the concept that many road users are also customers of a cellular operator, we show that specific road conditions map to certain signaling patterns in the cellular core network. In order to estimate the road traffic, signaling is(More)
We consider the optimization of the Core Network section of a mobile cellular network. While we focus on GPRS the proposed method can be applied to UMTS as well. The problem is to find an optimal assignment of PCUs (Packet Control Units, a module of the BSC) to SGSNs based on measured data. Two concurrent optimization goals apply: balance the number(More)
A 3G network is a magnificently complex object embedded in a highly heterogeneous and ever-changing usage environment. It combines the functional complexity of the wireless cellular paradigm with the protocol dynamics of TCP=IP networks. Understanding such an environment is more urgent and at the same time more difficult than for legacy 2G networks.(More)
INTRODUCTION Bipolar disorder (BD) is a chronic psychiatric disease which can take most different and unpredictable courses. It is accompanied by unspecific brainstructural changes and cognitive decline. The neurobiological underpinnings of these processes are still unclear. Emerging evidence suggests that tryptophan catabolites (TRYCATs), which involve all(More)
  • 1