Impact of denial of service solutions on network quality of service

The Internet has become a universal communication network tool. It has evolved from a platform that supports best-effort traffic to one that now carries different traffic types including those involving continuous media with quality of service (QoS) requirements. As more services are delivered over the Internet, we face increasing risk to their availability given that malicious attacks on those Internet services continue to increase. Several networks have witnessed denial of service (DoS) and distributed denial of service (DDoS) attacks over the past few years which have disrupted QoS of network services, thereby violating the Service Level Agreement (SLA) between the client and the Internet Service Provider (ISP). Hence DoS or DDoS attacks are major threats to network QoS. In this paper we survey techniques and solutions that have been deployed to thwart DoS and DDoS attacks and we evaluate them in terms of their impact on network QoS for Internet services. We also present vulnerabilities that can be exploited for QoS protocols and also affect QoS if exploited. In addition, we also highlight challenges that still need to be addressed to achieve end-to-end QoS with recently proposed DoS/DDoS solutions. © 2010 John Wiley & Sons, Ltd.

Clinical characteristics of patients with epilepsy in a specialist neuropsychiatry service

Neuropsychiatry services provide specialist input into the assessment and management of behavioral symptoms associated with a range of neurological conditions, including epilepsy. Despite the centrality of epilepsy to neuropsychiatry and the recent expansion of neuropsychiatry service provision, little is known about the clinical characteristics of patients with epilepsy who are routinely seen by a specialist neuropsychiatry service. This retrospective study filled this gap by retrospectively evaluating a naturalistic series of 60 consecutive patients with epilepsy referred to and assessed within a neuropsychiatry setting. Fifty-two patients (86.7%) had active epilepsy and were under the ongoing care of the referring neurologist for seizure management. The majority of patients (N = 42; 70.0%) had a diagnosis of localization-related epilepsy, with temporal lobe epilepsy as the most common epilepsy type (N = 37; 61.7%). Following clinical assessment, 39 patients (65.0%) fulfilled formal diagnostic criteria for at least one psychiatric disorder; nonepileptic attack disorder (N = 37; 61.7%), major depression (N = 23; 38.3%), and generalized anxiety disorder (N = 16; 26.7%) were the most commonly diagnosed comorbidities. The clinical characteristics of patients seen in specialist neuropsychiatry settings are in line with the results from previous studies in neurology clinics in terms of both epilepsy and psychiatric comorbidity. Our findings confirm the need for the development and implementation of structured care pathways for the neuropsychiatric aspects of epilepsy, with focus on comorbid nonepileptic attacks and affective and anxiety symptoms. This is of particular importance in consideration of the impact of behavioral symptoms on patients' health-related quality of life.