Mobile IP: state of the art report

Due to roaming, a mobile device may change its network attachment each time it moves to a new link. This might cause a disruption for the Internet data packets that have to reach the mobile node. Mobile IP is a protocol, developed by the Mobile IP Internet Engineering Task Force (IETF) working group, that is able to inform the network about this change in network attachment such that the Internet data packets will be delivered in a seamless way to the new point of attachment. This document presents current developments and research activities in the Mobile IP area

Securing Handover in Wireless IP Networks

In wireless and mobile networks, handover is a complex process that involves multiple layers of protocol and security executions. With the growing popularity of real time communication services such as Voice of IP, a great challenge faced by handover nowadays comes from the impact of security implementations that can cause performance degradation especially for mobile devices with limited resources. Given the existing networks with heterogeneous wireless access technologies, one essential research question that needs be addressed is how to achieve a balance between security and performance during the handover. The variations of security policy and agreement among different services and network vendors make the topic challenging even more, due to the involvement of commercial and social factors. In order to understand the problems and challenges in this field, we study the properties of handover as well as state of the art security schemes to assist handover in wireless IP networks. Based on our analysis, we define a two-phase model to identify the key procedures of handover security in wireless and mobile networks. Through the model we analyze the performance impact from existing security schemes in terms of handover completion time, throughput, and Quality of Services (QoS). As our endeavor of seeking a balance between handover security and performance, we propose the local administrative domain as a security enhanced localized domain to promote the handover performance. To evaluate the performance improvement in local administrative domain, we implement the security protocols adopted by our proposal in the ns-2 simulation environment and analyze the measurement results based on our simulation test

Managing Access Control in Virtual Private Networks

Virtual Private Network technology allows remote network users to benefit from resources on a private network as if their host machines actually resided on the network. However, each resource on a network may also have its own access control policies, which may be completely unrelated to network access. Thus users� access to a network (even by VPN technology) does not guarantee their access to the sought resources. With the introduction of more complicated access privileges, such as delegated access, it is conceivable for a scenario to arise where a user can access a network remotely (because of direct permissions from the network administrator or by delegated permission) but cannot access any resources on the network. There is, therefore, a need for a network access control mechanism that understands the privileges of each remote network user on one hand, and the access control policies of various network resources on the other hand, and so can aid a remote user in accessing these resources based on the user\u27s privileges. This research presents a software solution in the form of a centralized access control framework called an Access Control Service (ACS), that can grant remote users network presence and simultaneously aid them in accessing various network resources with varying access control policies. At the same time, the ACS provides a centralized framework for administrators to manage access to their resources. The ACS achieves these objectives using VPN technology, network address translation and by proxying various authentication protocols on behalf of remote users

WI-FI ALLIANCE HOTSPOT 2.0 SPECIFICATION BASED NETWORK DISCOVERY, SELECTION, AUTHENTICATION, DEPLOYMENT AND FUNCTIONALITY TESTS.

The demand for high mobile data transmission has been dramatically enlarged since there is a significant increase at the number of mobile communication devices that capable of providing high data rates. It is clearly observed that even the next generation cellular networks are not able to respond to this demand to provide the required level of mobile data transmission capacity. Although, WLAN responses to this demand by providing upwards of 600 Mbps data rates it is not convenient in terms of cellular like mobility and requires user intervention anytime of reconnection to a hotspot. Therefore, the need for a new technology took place and IEEE has introduced a new amendment to IEEE 802.11 standards family which is called as IEEE 802.11u. Based on IEEE 802.11u amendment, WFA developed WFA Hotspot 2.0 Specification and started to certify the Wi-Fi devices under Passpoint certification program. This new technology developed to provide Wi-Fi capable devices simply identify, select and associate to a Hotspot without any user intervention in a highly secure manner. As Hotspot 2.0 Specification is quite new in the market it has been a challenging work to reach some academic papers; however, IEEE 802.11u standard, Internet sources, white papers published by different companies/organizations and discussions with telecommunication experts have made this master thesis to achieve its goals. This thesis work provides a great resource for the network operators to have a great understanding of the Hotspot 2.0 Specification in terms of theory, network element requirements and deployment by providing a good understanding of the system functionality. In this paper, a comprehensive theoretical background that addresses to WLAN technology, Passpoint elements, and IEEE 802.11u based network discovery, selection and authentication is provided. Besides, Hotspot 2.0 network deployment scenarios with network core element requirements are designed and Passpoint functionality tests are performed under different scenarios by describing a comprehensive setup for the testing.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Greenpass RADIUS Tools for Delegated Authorization in Wireless Networks

Dartmouth\u27s Greenpass project extends how public key cryptography can be used to secure the wireless LAN with a RADIUS (Remote Authentication Dial In User Service) server that is responsible for handling authentication requests from clients (called supplicants in the 802.1x authentication model). This thesis describes the design and implementation of the authentication process of Greenpass, specifically what decisions are made in determining who is granted access and how a small modification of already existing protocols can be used to provide guest access in a way that better reflects how delegation of authority works in the real world. Greenpass takes advantage of the existing PKI to authenticate local Dartmouth users via X.509 identity certificates using EAP-TLS. We use the flexibility of SPKI/SDSI (Simple Public Key Infrastructure/Simple Distributed Security Infrastructure) authorization certificates to distribute the responsibility of delegating access to guests to certain authorized delegators, avoiding some of the necessary steps and paperwork associated with having a large centralized entity responsible for the entire institution. This thesis also discusses how our solution can be adapted to support different methods of guest delegation and investigates the possibility of eliminating the cumbersome central entity and administrative overhead traditionally associated with public key cryptography

Simultaneous multi-access in heterogeneous mobile networks

The exponential growth of the number of multihomed mobile devices is changing the way how we connect to the Internet. Unfortunately, it is not yet easily possible to a multihomed device to be simultaneously connected to the network through multiple links. This work enhances the network access of multihomed devices. This enhancement is achieved by using simultaneously all of the mobile devices interfaces, and by individually routing each data flow through the most adequate technology. The proposed solution is only deployed at the network core and it does not depend on the mobile devices, i.e., it’s transparent to the mobile devices. This work gives the necessary tools to reuse the already deployed technologies like WiFi or 3G/LTE. Moreover, it is also possible to extend the network by using femtocells which support multi access technologies. This work is also integrated with IEEE 802.21 standard to improve the handover mechanisms in the network. Additionally, we also propose an integration with a broker that can manage all the data flows individually. The proposed solution improves the quality of service of the users while not overloading the operator infrastructure. Evaluation results, obtained from the developed prototype, evidence that the overhead for using the proposed solution is very small when compared to the advantages.O crescimento exponencial do número de equipamentos móveis com múltiplas tecnologias de acesso à rede está a mudar a maneira como nos ligamos à Internet. Infelizmente, ainda não é possível usar simultaneamente todas as interfaces de rede de um equipamento móvel. Este trabalho melhora o acesso à rede a partir de dispositivos móveis com múltiplas interfaces de rede. Para alcançar esta melhoria todas as interfaces de rede dos dispositivos móveis podem ser usadas simultaneamente, e os fluxos de tráfego são encaminhados individualmente através da tecnologia mais conveniente. A solução proposta apenas é instalada na rede core, ou seja, é transparente para os equipamentos móveis. Este trabalho desenvolveu as ferramentas necessárias para reutilizar as tecnologias existentes que já estão disponíveis em larga escala, como o WiFi ou o 3G/LTE. É também possível usar femto-­células com suporte a múltiplas tecnologias de acesso para expandir mais rapidamente a rede. Este trabalho criou também uma integração com a norma IEEE 802.21 para melhorar os processos de handover. Adicionalmente propomos a integração com um broker externo para uma melhor gestão dos fluxos de tráfego. A solução proposta melhora a qualidade de serviço dos utilizadores sem sobrecarregar a infra-­estrutura do operador. Os resultados obtidos a partir dos testes realizados ao protótipo desenvolvido mostram que o impacto na performance ao usar esta solução é extremamente reduzido quando comparado com as suas vantagens

Non-repudiation Service Implementation Using Host Identity Protocol

New types of service usages emerge every day in the Internet. Service usage could be Wireless Local Area Network (WLAN) usage or watching a streamed movie. Many of these services are commercial, so payment is often involved in the service usage, which increases the risk of fraud or other misbehaviour in the interaction. To enhance the secu-rity of both service providers and service users, improvements are needed to the existing procedures. The non-repudiable service usage procedure was developed as part of the TIVIT Future Internet SHOK -project. In this model, the service user and the service provider are bound to the actual service usage with certificates. The charging of the service usage is done using hash chains which are bound to the certificates. Now the service user pays only for the service he or she gets. Time or traffic based charging scheme can be used in the service usage. Evidence is gathered from the service usage to help solve possible conflicts afterwards. An actual implementation based on this model was made using Host Identity Protocol for Linux and RADIUS protocol. RADIUS protocol was used to gather the created evidence of the service usage. The implementation was developed for Linux using C-language. The goal of the implementation was to evaluate the concept in actual use. Performance of the implementation was measured with various real use scenarios to evaluate the feasibility of the implementation. Results indicated that the performance of the model is sufficient to serve several simultaneous users. However, the architecture of Host Identity Protocol for Linux caused some performance issues in the implementation

Non-repudiation Service Implementation Using Host Identity Protocol

New types of service usages emerge every day in the Internet. Service usage could be Wireless Local Area Network (WLAN) usage or watching a streamed movie. Many of these services are commercial, so payment is often involved in the service usage, which increases the risk of fraud or other misbehaviour in the interaction. To enhance the secu-rity of both service providers and service users, improvements are needed to the existing procedures. The non-repudiable service usage procedure was developed as part of the TIVIT Future Internet SHOK -project. In this model, the service user and the service provider are bound to the actual service usage with certificates. The charging of the service usage is done using hash chains which are bound to the certificates. Now the service user pays only for the service he or she gets. Time or traffic based charging scheme can be used in the service usage. Evidence is gathered from the service usage to help solve possible conflicts afterwards. An actual implementation based on this model was made using Host Identity Protocol for Linux and RADIUS protocol. RADIUS protocol was used to gather the created evidence of the service usage. The implementation was developed for Linux using C-language. The goal of the implementation was to evaluate the concept in actual use. Performance of the implementation was measured with various real use scenarios to evaluate the feasibility of the implementation. Results indicated that the performance of the model is sufficient to serve several simultaneous users. However, the architecture of Host Identity Protocol for Linux caused some performance issues in the implementation

Greenpass Client Tools for Delegated Authorization in Wireless Networks

Dartmouth\u27s Greenpass project seeks to provide strong access control to a wireless network while simultaneously providing flexible guest access; to do so, it augments the Wi-Fi Alliance\u27s existing WPA standard, which offers sufficiently strong user authentication and access control, with authorization based on SPKI certificates. SPKI allows certain local users to delegate network access to guests by issuing certificates that state, in essence, he should get access because I said it\u27s okay. The Greenpass RADIUS server described in Kim\u27s thesis [55] performs an authorization check based on such statements so that guests can obtain network access without requiring a busy network administrator to set up new accounts in a centralized database. To our knowledge, Greenpass is the first working delegation-based solution to Wi-Fi access control. My thesis describes the Greenpass client tools, which allow a guest to introduce himself to a delegator and allow the delegator to issue a new SPKI certificate to the guest. The guest does not need custom client software to introduce himself or to connect to the Wi-Fi network. The guest and delegator communicate using a set of Web applications. The guest obtains a temporary key pair and X.509 certificate if needed, then sends his public key value to a Web server we provide. The delegator looks up her guest\u27s public key and runs a Java applet that lets her verify her guests\u27 identity using visual hashing and issue a new SPKI certificate to him. The guest\u27s new certificate chain is stored as an HTTP cookie to enable him to push it to an authorization server at a later time. I also describe how Greenpass can be extended to control access to a virtual private network (VPN) and suggest several interesting future research and development directions that could build on this work.My thesis describes the Greenpass client tools, which allow a guest to introduce himself to a delegator and allow the delegator to issue a new SPKI certificate to the guest. The guest does not need custom client software to introduce himself or to connect to the Wi-Fi network. The guest and delegator communicate using a set of Web applications. The guest obtains a temporary key pair and X.509 certificate if needed, then sends his public key value to a Web server we provide. The delegator looks up her guest\u27s public key and runs a Java applet that lets her verify her guests\u27 identity using visual hashing and issue a new SPKI certificate to him. The guest\u27s new certificate chain is stored as an HTTP cookie to enable him to push it to an authorization server at a later time. I also describe how Greenpass can be extended to control access to a virtual private network (VPN) and suggest several interesting future research and development directions that could build on this work