In many communication system implementations, such as M-ary PSK and FSK modems, DMT for ADSL, as well as carrier and clock synchronization, the efficient conversion from rectangular to polar coordinates is essential. In this paper, we present a novel architecture for a circuit that computes the angle, as well as the magnitude, of a polar-form representation of a complex number, given the real a...

To overcome quality of experience degradation due to the saturation of the uplink of ADSL lines, we propose in this paper the Shortest Queue First (SQF) queuing discipline to sort packets out of the buffer associated with the uplink of a home gateway. SQF is a flow aware queuing discipline which consists of serving those flows creating the less backlog in the buffer. We show experimental result...

the various flavors of Asymmetric DSL (ADSL), which are limited to 1.104 or 2.208 MHz, and are designed for operation over relatively long loops. VDSL is particularly vulnerable to crosstalk for both the downstream and the upstream transmission directions; its data rate performance is typically limited by Far-End-Crosstalk (FEXT). This means that in practical deployments, where multiple pairs a...

This reaction is analogous to the aspartase reaction and to the enzymic condensation of arginine and fumaric acid (2). In this paper a more detailed characterization of the adenylosuccinase reaction and the product of the reaction, adenylosuccinic acid, is reported. A synthesis of the aglycone of adenylosuccinic acid, 6-succinoaminopurine, from aspartic acid and 6chloropurine, which confirms th...

As the broadband information highway being constructed, many multimedia applications will be realized. Nowadays, customers desired not only purely high-speed Internet access, but also versatile interactive multimedia applications. This article illustrates a multimedia-on-demand (MOD) system that can be provided by incumbent telcos. It provides both multicast and unicast streaming services, incl...

This document presents Shortest Queue First (SQF) packet scheduling algorithm, as a solution to improve Internet access on ADSL links. This queuing policy provides implicit service differentiation, avoiding the need of packet marking and resource reservation associated to usual Quality of Service (QoS) architectures like Differentiated Services (DiffServ) and Integrated Services (IntServ). SQF ...

The lack of widely available broadband internet access available in all parts of Germany was the main motivation to build community mesh networks to share ADSL lines. As many are unable to easily obtain an ADSL line, we built a wireless mesh network covering our two home villages. Singe we began, we have included 60 households running their own 802.11 wireless routers based on commodity hardwar...

We study functionally correct TCP connections – normal set-up, data transfer and tear-down – that experience lower than normal performance in terms of delay and throughput. Several factors, including packet loss or application behavior, may lead to such abnormal performance. We present a methodology to detect TCP connections with such abnormal performance from packet traces recorded at a single...

This memo is a digest of the user network interface specification of NTT Communications’ dual stack ADSL access service, which provide a IPv6/IPv4 dual stack services to home users. In order to simplify user setup, these services have a mechanism to configure IPv6 specific parameters automatically. The memo focuses on two basic parameters: the prefix assigned to the user and the addresses of IP...

Analysis is done on the inter-carrier interference (ICI) that caused by multi-carrier communication system frequency offset. The application model of DFT/IDFT in ADSL access network is analyzed further; the hardware detection and software analysis scheme of the system are proposed for the accessing network. Experiments have proved that monitoring system can filter the network data flow and carr...