144,950 research outputs found

    Electronic swallowing intervention package to support swallowing function in patients with head and neck cancer: development and feasibility study

    Get PDF
    Background: Many patients undergoing treatment for head and neck cancer (HNC) experience significant swallowing difficulties, and there is some evidence that swallowing exercises may improve outcomes, including quality of life. This feasibility study developed an evidence-based, practical Swallowing Intervention Package (SiP) for patients undergoing chemo-radiotherapy (CRT) for HNC. As part of the study, an electronic version of SiP (e-SiP) was concurrently developed to support patients to self-manage during treatment. This paper reports on the e-SiP component of this work. Objective: To develop and conduct preliminary evaluation of an electronic support system (e-SiP) for patients undergoing CRT for head and neck cancer. Methods: The study involved health professionals and patients who were undergoing CRT for head and neck cancer. The scoping stage of e-SiP development involved investigated the potential usefulness of e-SiP, exploring how e-SiP would look and feel and what content would be appropriate to provide. Patient and carer focus groups and a health professionals’ consensus day were used as a means of data gathering around potential e-SiP content. A repeat focus group looked at an outline version of e-SIP and informed the next stage of its development around requirements for tool. This was followed by further development and a testing stage of e-SiP involved the coding of a prototype which was then evaluated using a series of steering group meetings, semi-structured interviews with both patients and health care professionals, and analysis of e-SiP log data. Results: Feedback from focus groups and health professional interviews was very positive and it was felt e-SiP use would support and encourage patients in conducting their swallowing exercises. However, of the ten patients offered e-SIP, only two opted to use it. For these patients, aspects of the e-SIP application were considered useful, in particular the ease of keeping a diary of exercises performed. Interviews with users and non-users suggested significant barriers to its use. Most significantly the lack of flexibility of platform on which e-SiP could be accessed appeared a dominant factor in deterring e-SiP use. Conclusions: Results suggest a need for further research to be conducted around the implementation of e-SiP. This involves evaluating how e-SiP can be better integrated into usual care, and through patient training and staff engagement, can be seen as a beneficial tool to help support patients in conducting swallowing exercises

    ALEX: Improving SIP Support in Systems with Multiple Network Addresses

    Get PDF
    The successful and increasingly adopted session initiation protocol (SIP) does not adequately support hosts with multiple network addresses, such as dual-stack (IPv4-IPv6) or IPv6 multi-homed devices. This paper presents the Address List Extension (ALEX) to SIP that adds effective support to systems with multiple addresses, such as dual-stack hosts or multi-homed IPv6 hosts. ALEX enables IPv6 transport to be used for SIP messages, as well as for communication sessions between SIP user agents (UAs), whenever possible and without compromising compatibility with ALEX-unaware UAs and SIP servers

    A new security architecture for SIP based P2P computer networks

    Get PDF
    Many applications are transferred from C/S (Client/Server) mode to P2P (Peer-to-Peer) mode such as VoIP (Voice over IP). This paper presents a new security architecture, i.e. a trustworthy authentication algorithm of peers, for Session Initialize Protocol (SIP) based P2P computer networks. A mechanism for node authentication using a cryptographic primitive called one-way accumulator is proposed to secure the P2P SIP computer networks. It leverages the distributed nature of P2P to allow for distributed resource discovery and rendezvous in a SIP network, thus eliminating (or at least reducing) the need for centralized servers. The distributed node authentication algorithm is established for the P2P SIP computer networks. The corresponding protocol has been implemented in our P2P SIP experiment platform successfully. The performance study has verified the proposed distributed node authentication algorithm for SIP based P2P computer networks

    Telephony Denial of Service Defense at Data Plane (TDoSD@DP)

    Get PDF
    The Session Initiation Protocol (SIP) is an application-layer control protocol used to establish and terminate calls that are deployed globally. A flood of SIP INVITE packets sent by an attacker causes a Telephony Denial of Service (TDoS) incident, during which legitimate users are unable to use telephony services. Legacy TDoS defense is typically implemented as network appliances and not sufficiently deployed to enable early detection. To make TDoS defense more widely deployed and yet affordable, this paper presents TDoSD@DP where TDoS detection and mitigation is programmed at the data plane so that it can be enabled on every switch port and therefore serves as distributed SIP sensors. With this approach, the damage is isolated at a particular switch and bandwidth saved by not sending attack packets further upstream. Experiments have been performed to track the SIP state machine and to limit the number of active SIP session per port. The results show that TDoSD@DP was able to detect and mitigate ongoing INVITE flood attack, protecting the SIP server, and limiting the damage to a local switch. Bringing the TDoS defense function to the data plane provides a novel data plane application that operates at the SIP protocol and a novel approach for TDoS defense implementation.Final Accepted Versio

    E−H Bond Activation Reactions (E = H, C, Si, Ge) at Ruthenium: Terminal Phosphides, Silylenes, and Germylenes

    Get PDF
    The placement of a strongly trans-influencing ligand on a ruthenium center opposite an anchoring silyl group of the tetradentate tripodal tris(phosphino)silyl ligand, [SiP^(Ph)_3]^− ([SiP^(Ph)_3]^− = tris(2-(diphenylphosphino)phenyl)silyl), has been explored. Installation of alkyl or terminal phosphide ligands trans to the anchoring silyl group affords the complexes [SiPPh3]RuR (R = Me (2), CH_2Ph (4), PPh_2 (5), P^iPr_2 (6)). Complexes 2, 4, and 5 are thermally unstable. Complexes 2 and 4 decay to the cyclometalated complex [SiP^(Ph)_2P′^(Ph)]Ru (3), whereas complex 5 decays to the cyclometalated phosphine adduct [SiP^(Ph)_2P′^(Ph)]Ru(PHPh_2) (7). Complex 3 is found to effect E−H (E = H, C, Si, Ge) bond activation of substrates such as secondary silanes and germanes to yield the structurally unusual silylene complexes [SiP^(Ph)_3]Ru(H)(SiRR′) (R = R′ = Ph (10a), R = Ph R′ = Me (10b)) and the germylene complex [SiP^(Ph)_3]Ru(H)(GeR_2) (R = Ph) (11) via double E−H activation transformations. Both theory and experiments suggest electrophilic character at the silylene moiety. Reaction of 3 with catecholborane, in contrast to silanes and germanes, results in insertion of the B−H unit into the M−C bond of the cyclometalated species to yield the borate complex [SiP^(Ph)_2P^(Ph)-B(cat)]Ru(μ-H) (14). Complex 3 also reacts with bis(catecholato)diboron to yield a similar complex, [SiP^(Ph)_2P^(C6H3B(cat))-B(cat)]Ru(μ-H) (15), with selective borylation of an ortho C−H bond

    Session Initiation Protocol Attacks and Challenges

    Full text link
    In recent years, Session Initiation Protocol (SIP) has become widely used in current internet protocols. It is a text-based protocol much like Hyper Text Transport Protocol (HTTP) and Simple Mail Transport Protocol (SMTP). SIP is a strong enough signaling protocol on the internet for establishing, maintaining, and terminating session. In this paper the areas of security and attacks in SIP are discussed. We consider attacks from diverse related perspectives. The authentication schemes are compared, the representative existing solutions are highlighted, and several remaining research challenges are identified. Finally, the taxonomy of SIP threat will be presented
    corecore