A Review on Sensor Network Issues and Robotics <s> Security Issues in Mobile Ad Hoc Sensor Networks <s> Security in mobile ad hoc networks is difficult to achieve, notably because of the vulnerability of wireless links, the limited physical protection of nodes, the dynamically changing topology, the absence of a certification authority, and the lack of a centralized monitoring or management point. Earlier studies on mobile ad hoc networks (MANETs) aimed at proposing protocols for some fundamental problems, such as routing, and tried to cope with the challenges imposed by the new environment. These protocols, however, fully trust all nodes and do not consider the security aspect. They are consequently vulnerable to attacks and misbehavior. More recent studies focused on security problems in MANETs, and proposed mechanisms to secure protocols and applications. This article surveys these studies. It presents and discusses several security problems along with the currently proposed solutions (as of July 2005) at different network layers of MANETs. Security issues involved in this article include routing and data forwarding, medium access, key management and intrusion detection systems (IDSs). This survey also includes an overview of security in a particular type of MANET, namely, wireless sensor networks (WSNs). <s> BIB001 </s> A Review on Sensor Network Issues and Robotics <s> Security Issues in Mobile Ad Hoc Sensor Networks <s> Wireless Sensor Networks (WSNs) are used in many applications in military, ecological, and health-related areas. These applications often include the monitoring of sensitive information such as enemy movement on the battlefield or the location of personnel in a building. Security is therefore important in WSNs. However, WSNs suffer from many constraints, including low computation capability, small memory, limited energy resources, susceptibility to physical capture, and the use of insecure wireless communication channels. These constraints make security in WSNs a challenge. In this article we present a survey of security issues in WSNs. First we outline the constraints, security requirements, and attacks with their corresponding countermeasures in WSNs. We then present a holistic view of security issues. These issues are classified into five categories: cryptography, key management, secure routing, secure data aggregation, and intrusion detection. Along the way we highlight the advantages and disadvantages of various WSN security protocols and further compare and evaluate these protocols based on each of these five categories. We also point out the open research issues in each subarea and conclude with possible future research directions on security in WSNs. <s> BIB002
Because of the vulnerability of wireless links, nodes limited physical protection, nonexistence of certification authority, and lack of management point or a centralized monitoring, it is difficult to achieve security in mobile ad hoc networks BIB001 . Sensor networks have many applications: they are used in ecological, military, and health related areas. These applications often examine some sensitive information such as location detection or enemy movement on the battlefields. Therefore security is very important in WSN. WSN has many limitations such as small memory, limited energy resources, and use of insecure channels in communication; these problems make security in WSN a challenge BIB002 . Designing the security schemes of wireless sensor networks is not an easy task; sensor networks have many constraints compared to computer networks  . The main objective of the security service in WSN is to protect the valuable information and resources from misbehavior and attacks; requirements in wireless sensor network security include availability, authorization, confidentiality, authentication, integrity, nonrepudiation, and freshness. Attacks in WSN can be categorized as follows: attacks on network availability: these are often referred to as DOS (denial of service attacks); these attacks can target any layer of a sensor network. Attacks on secrecy and authentication include packet replay attacks, eavesdropping, or spoofing of attacks. There are also stealthy attacks against service integrity. In this type of attack the motive of the attacker is to make network accept false data value. Security threats and issues in WSN can be classified into two categories: active and passive attacks  .