A Secure and Anonymous Cooperative Sensing Protocol for Cognitive Radio Networks

Spectrum is an essential resource for the provision of mobile services. In order to control and delimit its use, governmental agencies set up regulatory policies. Unfortunately, such policies have led to a deficiency of spectrum as only few frequency bands are left unlicensed, and these are used for the majority of new emerging wireless applications. One promising way to alleviate the spectrum shortage problem is adopting a spectrum sharing paradigm in which frequency bands are used opportunistically. Cognitive radio is the key technology to enable this shift of paradigm.Cognitive radio networks are self-organized systems in which devices cooperate to use those spectrum ranges that are not occupied by licensed users. They carry out spectrum sensing in order to detect vacant channels that can be used for communication. Even though spectrum sensing is an active area of research, an important issue remains unsolved: the secure authentication of sensing reports. Not providing security enables the input of false data in the system thus empowering false results. This paper presents a distributed protocol based on wireless physical layer security, symmetric cryptography and one-way functions that allows determining a final sensing decision from multiple sources in a quick and secure way, as well as it preserves users¿ privacy.

Experimental evaluation of anonymous protocols under the JXTA middleware

JXTA is a peer-to-peer (P2P) middleware whichhas undergone successive iterations through its 10 years of history, slowly incorporating a security baseline that may cater to different applications and services. However, in order to appeal to a broader set of secure scenarios, it would be interesting to take into consideration more advanced capabilities, such as anonymity.There are several proposals on anonymous protocols that can be applied in the context of a P2P network, but it is necessary to be able to choose the right one given each application¿s needs. In this paper, we provide an experimental evaluation of two relevant protocols, each one belonging to a different category of approaches to anonymity: unimessage and split message. Webase our analysis on two scenarios, with stable and non-stable peers, and three metrics: round trip-time (RTT), node processing time and reliability.

An Ethic of Connectedness: Book Review of The Connected Self: The Ethics and Governance of the Genetic Individual

Compte-rendu / Review

Commonplace book of Benjamin Penhallow, 1721-1724

This leather-bound volume contains excerpts copied by Benjamin Penhallow from books he read while he was a student at Harvard in the 1720s. The volume contains extracts from two texts: Johanis Henrici Alstedii's (John Henry Alsted / Johann Heinrich Alsted) Geometria Domini, and the anonymous text "The Legacy of a dying Father; bequeath'd to his Beloved Children, or Sundry Directions in Order unto a well Regulated Conversation," from 1724 (originally published in 1693-4). The last page of text in the volume contains the hymn "The Sacred Content of Praise" first published in 1734, and added after Penhallow's death.

Inventory of Silver Plate, Belonging to Harvard College, and in the Keeping of the President, 1886 December 8

Black and white composition book sent to the Harvard College Library containing a typed "copy of notes made in the spring of 1886" by John H. Buck. Includes historical information, and physical descriptions and valuations of the Great Salt, the Stoughton Cup, the Browne Cup, and the christening basin acquired with the donation of Oliver Wendell, as well as notes on other gifts of silver.

The book of Elizabethan verse,

Issued also as the first in a series of four volumes to cover British poetry from the publication of Tottel's miscellany, 1557; the other volumes being The book of restoration verse, The book of Georgian verse, and The book of Victorian verse (not yet published?)

The study-book of mediæval architecture and art; being a series of working drawings of the principal monuments of the middle ages. Whereof the plans, sections, and details are drawn to uniform scales.

Mode of access: Internet.

One hundred and seventy-six historic and artistic book-bindings dating from the fifteenth century to the present time pictured by etchings, artotypes, and lithographs after the originals selected from the library of Robert Hoe ...

"The edition consists of two hundred copies only, all printed upon imperial Japanese paper."

The book of orders of knighthood and decorations of honour of all nations, comprising a historical account of each order, military, naval, and civil, from the earliest to the present time, with lists of the knights and companions of each British order ...

Plate 1 missing.

The Chinese rug book,

Each plate accompanied by leaf with descriptive letterpress.

The book makers of old Birmingham: authors, printers, and book sellers,

One plate printed on both sides.

The butterfly book; a popular guide to a knowledge of the butterflies of North America,

Each plate accompanied by guard sheet with descriptive letterpress.

A book of trout flies; containing a list of the most important American stream insects & their imitations,

Edited by Dr. Spieth. cf. Pref.

A book of porcelain, fine examples in the Victoria & Albert museum,

Each plate accompanied by leaf with descriptive letterpress.

Disegni del Mantegna.

An additional plate is a photograph from a plate in the British Museum copy.