The power consumption of wireless access networks will become an important issue in the coming years. In this paper the power consumption of base stations for mobile WiMAX, fixed WiMAX and UMTS is modelled. This power consumption is evaluated in relation to the coverage. For a physical bit rate of 2 Mbps, a power consumption of approximately 5600 W and a range of 1 km is obtained with UMTS. Fix...

During the design of ABR tra c management at the ATM Forum, we performed several analyses to ensure that the ABR service will operate e ciently over satellite links. In the cases where the performance was unacceptable, we suggested modi cations to the tra c management speci cations. This paper describes one such issue related to the count of missing resource management cells (Crm) parameter of ...

In a SONET/SDH network the frame alignment is an important function. This paper presents a component that realizes it and the section layer functionality in a SONET/SDH network. The user can choose between STS-1/STM-0 at 51.48 Mbps or STS-3/STM-1 at 154.44 Mbps operation. There are some components to do frame alignment [1] but here we present a new component with a wider range of functions. The...

Bandwidth-intensive applications compete directly with the operating system’s network stack for CPU cycles. This is particularly true when the stack performs security protocols such as IPsec; the additional load of complex cryptographic transforms overwhelms modern CPUs when data rates exceed 100 Mbps. This paper describes a network-processing accelerator which overcomes these bottlenecks by of...

The Brazilian government intends to use the Digital TV technology as a vehicle of digital inclusion on underserved communities. The wireless ad hoc network is a low-cost, scalable and easy solution to implement the return channel. This work analyzes the performance of an ad hoc return channel using the wireless IEEE 802.11 technology in different Brazilian geographical scenarios. The results sh...

While bandwidth for previous IP backbone networks deployed by Internet Service Providers typically has been limited to 34 Mbps, current and future IP networks provide bandwidth ranging from 155 Mbps to 2.4 Gbps. Thus, it is important to investigate the impact of emerging network technologies on the performance of cooperative Web caching protocols. In this paper, we present a comprehensive perfo...

With the recent media attention on UWB and the announcements of 22 UWB based Wireless-USB (W-USB) products being certified by the WiMedia Alliance, the time has come to evaluate this exciting new wireless technology and see if it has delivered on the promise of transporting hundreds of megabits per second and superior QoS. This test was organized under the aegis of EE Times and our plan was to ...

282 Abstract—IPv4 address space will run out in the next two years. Therefore, it is necessary to deploy the new version of the Internet Protocol (IPv6) which dramatically expands the address space. One important issue for IPv6 to gain acceptance, is its end-to-end performance. For this reason, it is important to offer the Internet community some tools to compare IPv4 and IPv6 performance. In t...

Classifying network flows into applications is a fundamental requirement for network administrators. Administrators used to classify network applications by examining transport layer port numbers or application level signatures. However, emerging network applications often send encrypted traffic with randomized port numbers. This makes it challenging to detect and manage network applications. I...

In this work, we have conducted experiments to evaluate QoS of VoIP applications over the WiBro network. In order to capture the baseline performance of the WiBro network we measure and analyze the characteristics of delay and throughput under stationary and mobile scenarios. Then we evaluate QoS of VoIP applications using the E–Model of ITU–T G.107. Our measurements show that the achievable ma...