In this paper we investigate the acknowledgment procedures used at radio link control level of General Packet Radio Service (GPRS), where GPRS is a new GSM service designed for packet switched data transmission over GSM network. An introduction to the Radio Link Control and Medium Access Control

power control problem can be reduced to finding a vector p of users' transmitter powers satisfying p I(p) where the jth constraint p j I j (p) describes the interference that user j must overcome to achieve an acceptable connection. This work unifies results found for these systems

the discussion of interference temperature as a new metric for the quantification and management of interference, the paper addresses three fundamental cognitive tasks. 1) Radio-scene analysis. 2) Channel-state estimation and predictive modeling. 3) Transmit-power control and dynamic spectrum management

This paper anal yzes the causes of packetl oss in a 38-node urban mul ti-hop 802.11b network. The patterns and causes oflv# are important in the design of routing and errorcorrection proto colv as wel as in networkplqq"(v The paper makes the fol l owing observations. The distribution of inter-nodel oss rates is rel'RfivD' uniform over the wh ol range oflv$ rates; there is no clq$ threshol separating "in range" and "out of range." Mostls ks have relj tivel stabl el oss rates from one second to the next, though a smal l minority have very burstyl osses at that time scal e. Sign al to-noise ratio and distance have lv tl e predictive val e forl oss rate. Thel arge number of lv ks with intermediate l oss rates is probabl y due to mul ti-path fading rather than attenuation or interference. The phenomena discussed here are al l wel l -known. The contributions of this paper are an understanding of their rel ative importance, of how they interact, and of the impl ications for MAC and routing protocol design.

Abstract not found

This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC 2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as ‘‘work in progress.’’ The list of current Internet-Drafts can be accessed at

significantly limited the performance, flexibility, and functionality of applications. The exokernel architecture removes these limitations by allowing untrusted software to implement traditional operating system abstractions entirely at application-level. We have implemented a prototype exokernel-based system

the communication path, while still providing full protection. The model presented by U-Net allows for the construction of protocols at user level whose performance is only limited by the capabilities of network. The architecture is extremely flexible in the sense that traditional protocols like TCP and UDP

This paper proposes S-MAC, a medium access control (MAC) protocol designed for wireless sensor networks. Wireless sensor networks use battery-operated computing and sensing devices. A network of these devices will collaborate for a common application such as environmental monitoring. We expect

This paper proposes a mechanism for equation-based congestion control for unicast traffic. Most best-effort traffic in the current Internet is well-served by the dominant transport protocol, TCP. However, traffic such as best-effort unicast streaming multimedia could find use for a TCP