127 research outputs found

    How to Undo Things with Codes: New Writing Mechanisms and the Un/archivable Dis/appearing text

    Get PDF
    The discourses of criticism are being transformed at the same time that our writing mechanisms are undergoing a major change. Reflecting on the relationship between our writing tools and our perceptions and taking programmability and interactivity as the main characteristics of new writing media, this essay attempts an approach to how that which is new in scriptural techniques, that is to say, programmability and interactivity, are undoing our perception of such notions as the archive and embodiment. The two works which are here commented contain the conditions of unwriting their written trace; the interactor who makes the text appear paradoxically also causes its disappearance by acts of destruction or dispersion. In the case of AGRIPPA (A Book of The Dead), William Gibson reserves for the reader the role of the destructor of the text through an extreme gesture of interaction which destines the work to erasure and calls for the retrieval of a text that contains the conditions of its own death. In the case of Garry Hill‘s Writing Corpora, the body‘s acts are created of, create and are turned against writing, they embody and disperse the writing traces, while the body experiences the shift from inscription to embodiment

    2.5K-Graphs: from Sampling to Generation

    Get PDF
    Understanding network structure and having access to realistic graphs plays a central role in computer and social networks research. In this paper, we propose a complete, and practical methodology for generating graphs that resemble a real graph of interest. The metrics of the original topology we target to match are the joint degree distribution (JDD) and the degree-dependent average clustering coefficient (cˉ(k)\bar{c}(k)). We start by developing efficient estimators for these two metrics based on a node sample collected via either independence sampling or random walks. Then, we process the output of the estimators to ensure that the target properties are realizable. Finally, we propose an efficient algorithm for generating topologies that have the exact target JDD and a cˉ(k)\bar{c}(k) close to the target. Extensive simulations using real-life graphs show that the graphs generated by our methodology are similar to the original graph with respect to, not only the two target metrics, but also a wide range of other topological metrics; furthermore, our generator is order of magnitudes faster than state-of-the-art techniques

    Towards Unbiased BFS Sampling

    Full text link
    Breadth First Search (BFS) is a widely used approach for sampling large unknown Internet topologies. Its main advantage over random walks and other exploration techniques is that a BFS sample is a plausible graph on its own, and therefore we can study its topological characteristics. However, it has been empirically observed that incomplete BFS is biased toward high-degree nodes, which may strongly affect the measurements. In this paper, we first analytically quantify the degree bias of BFS sampling. In particular, we calculate the node degree distribution expected to be observed by BFS as a function of the fraction f of covered nodes, in a random graph RG(pk) with an arbitrary degree distribution pk. We also show that, for RG(pk), all commonly used graph traversal techniques (BFS, DFS, Forest Fire, Snowball Sampling, RDS) suffer from exactly the same bias. Next, based on our theoretical analysis, we propose a practical BFS-bias correction procedure. It takes as input a collected BFS sample together with its fraction f. Even though RG(pk) does not capture many graph properties common in real-life graphs (such as assortativity), our RG(pk)-based correction technique performs well on a broad range of Internet topologies and on two large BFS samples of Facebook and Orkut networks. Finally, we consider and evaluate a family of alternative correction procedures, and demonstrate that, although they are unbiased for an arbitrary topology, their large variance makes them far less effective than the RG(pk)-based technique.Comment: BFS, RDS, graph traversal, sampling bias correctio

    PhishDef: URL Names Say It All

    Full text link
    Phishing is an increasingly sophisticated method to steal personal user information using sites that pretend to be legitimate. In this paper, we take the following steps to identify phishing URLs. First, we carefully select lexical features of the URLs that are resistant to obfuscation techniques used by attackers. Second, we evaluate the classification accuracy when using only lexical features, both automatically and hand-selected, vs. when using additional features. We show that lexical features are sufficient for all practical purposes. Third, we thoroughly compare several classification algorithms, and we propose to use an online method (AROW) that is able to overcome noisy training data. Based on the insights gained from our analysis, we propose PhishDef, a phishing detection system that uses only URL names and combines the above three elements. PhishDef is a highly accurate method (when compared to state-of-the-art approaches over real datasets), lightweight (thus appropriate for online and client-side deployment), proactive (based on online classification rather than blacklists), and resilient to training data inaccuracies (thus enabling the use of large noisy training data).Comment: 9 pages, submitted to IEEE INFOCOM 201
    • …
    corecore