Knowledge Base

Title Authors Last Update Category
SuperDemo 2003 MFA

SuperDemo 2003 was the worlds most advanced and comprehensive live test of multiple MPLS services operating concurrently across a multi-vendor MPLS network. The MPLS/FR Alliance SuperDemo included 14 different companies showcasing MPLS services and features such as VPLS, ATM/FR/Ethernet over MPLS, BGP MPLS VPNs and Fast re-route.

June 9, 2003 White Papers
IEEE 802.11 TGe - QoS Enhancements (D6.0) Chris Polanec

Overview of Quality of Service (QoS) Enhancements for the MAC based on TGe draft 6.0.

September 18, 2014 Tutorials
Presentation on the 10GEC Bob Noseworthy

Presented at the 10Gigabit Ethernet User Conference, Nov 1 2002

November 5, 2002 Tutorials
An ITU-T G.994.1 Protocol Analysis Tool For ADSL Matthew Langlois (UNH-IOL), Dr. Michael Carter, Dr. William Lenharth, and Scott Valcourt

One of the most commonly deployed DSL variants is ADSL. Despite this fact, deployment of new robust and reliable ADSL services is increasingly difficult due, in part, to the physical limitations of the copper telephone system infrastructure, and also in part to the lack of useful ADSL network debugging tools. ADSL service providers and technicians currently lack a device capable of decoding physical layer signaling and displaying actual physical layer parameters and statistics associated with a live ADSL connection, independent of the end stations. Similar devices used in other network technologies are often referred to as protocol analyzers. The intent of this paper is to illustrate how Matlab [1], in conjunction with a DSP or a PC, can be used to create an effective ADSL handshaking protocol analyzer based on ITU-T G.994.1 (G.hs) [2]. G.hs conformance is critical in establishing a successful ITU-T G.992.1 (G.dmt) [3] based ADSL connection.

November 4, 2002 White Papers
Radio Frequency Interference and Capacity Reduction in DSL Padmabala Venugopal (UNH-IOL), Michael J. Carter, Scott A. Valcourt

The issue of radio frequency interference in Digital Subscriber Line (DSL) networks is of particular concern in urban areas with many strong radio sources nearby. This paper investigates in detail the mechanisms underlying the capacity reduction due to the presence of radio frequency signals from Amplitude Modulated (AM) broadcast stations in an ADSL network. An ADSL system, channel, and radio frequency interference noise were simulated in MATLAB. The capacity reduction due to different Radio Frequency (RF) ingress conditions was studied. Spectral Spreading of the RF interferer, as suggested by Harris et al [1], is a primary cause of capacity reduction, but only at long loop lengths where the signal to Gaussian noise ratio is very low.

November 4, 2002 White Papers
VDSL MCM Simulation Tim Clark (UNH-IOL)

An introduction to MCM for VDSL.

October 2, 2002 Tutorials
VDSL Modulation Schemes: MCM vs. SCM Tim Clark (UNH-IOL)

This presentation provides an overview and comparison of the two proposed VDSL modulation schemes.

October 2, 2002 Tutorials
Radio Frequency Interference in DSL and Capacity Reduction Padmabala Venugopal

The issue of radio frequency interference in Digital Subscriber Line (DSL) networks is of particular concern in urban areas with many strong radio sources nearby. Prior work by Harris et al showed drastic decreases in DSL link capacity with a narrowband AM interferer. The purpose of this thesis was to investigate in more detail the mechanisms underlying the capacity reduction observed by Harris. In this thesis, an ADSL system, channel, and radio frequency interference noise were simulated in MATLAB. The capacity reduction due to different RF ingress conditions was studied. It was found that a narrowband interferer does not cause a drastic decrease in capacity if time and frequency domain equalizers are employed in the receiver. Contrary to Harris?s suggestions that spectral spreading of the interferer is the primary cause of capacity reduction, it is shown in this thesis that such spreading is a secondary effect and that the unequalized channel is the predominant source of capacity reduction.

April 23, 2002 Theses
A G.hs Handshaking Protocol Analyzer For ADSL Matthew Langlois

A protocol analyzer is a device that non-intrusively monitors bi-directional communications on a link, demodulates the physical layer signals, and captures the raw binary data for subsequent state and timing analysis. There are no commercial products currently available that perform this function for ADSL link initialization procedures. In this project, a MATLAB application was developed that enables capture (via a digital sampling oscilloscope) and protocol analysis of the first segment, known as handshaking, of the ADSL link initialization procedure. The protocols of interest are ITU-T G.994.1 (G.hs), which defines the activation and handshaking procedures used by complaint ADSL equipment, and ITU-T G.992.1 (G.dmt), which defines the physical layer requirements of ADSL equipment utilizing the Discrete Multi-Tone (DMT) line code.

December 14, 2001 Theses
10 Gigabit Ethernet Clause 48 Tutorial Vinod Venkatavaradan

Clause 48 overview

December 12, 2001 Tutorials