The trend towards value-added Internet services causes network providers to deploy new network based quality-of-service and security services. Today, however, the customer has only limited means of controlling the service delivery. For example the network security guaranteed by virtual private network providers cannot be checked with a traditional static approach. This paper presents a novel ap...

Some networks require communication between an interior and exterior portion of a Virtual Private Network (VPN) or through a concatenation of such networks resulting in a nested VPN, but have sensitivities about what information is communicated across the boundary, especially while providing quality of service to communications with different precedence. This note seeks to outline the issues an...

This paper describes an architecture for the management of QoS-enabled virtual private networks (VPNs) over the Internet. The architecture focuses on two important issues of VPNs: security and Quality-of-Service (QoS). The security achieved in VPNs is based on IPSec tunnels, while QoS can be supported by mechanisms as proposed by the Differentiated Services currently being defined by the IETF. ...

The liberalisation of the telecommunications industry has resulted in a proliferation of new services and services providers. This is particularly the case in the rapidly expanding IP-based services market. Providers include Internet Service Providers (ISPs), Virtual Private Network (VPN), communication (backbone operators), and application service providers. The final service set delivered to ...

We study dual job incentives with a focus on public-service physicians referring patients to their private practices. We call this moonlighting. Not all physicians moonlight; we introduce a group of dedicated doctors who in the base models behave nonstrategically in the public system. Allowing moonlighting can always enhance aggregate welfare. The equilibrium care quality in the public system m...

In Part I we introduced a working definition of the term "Virtual Private Network" (VPN), and discussed the motivations behind the adoption of such networks. We outlined a framework for describing the various forms of VPNs, and then examined numerous network-layer VPN structures, in particular, that of controlled route leakage and tunnelling techniques. We begin Part II with examining other net...

In this paper, we propose and implementVirtual Network Service (VNS), a value-added network service for deploying virtual private networks (VPN) in a managed wide area IP network. The key feature of VNS is its capability of providing a customer with a VPN that is customizable with management capabilities and performance properties comparable to a dedicated physical network. In addition, VNS ens...

Low yield of maize continues to affect the livelihood of smallholder farmers in the Zabzugu-Tatale area despite the introduction of a high yielding Obatanpa maize variety. The study used a cross-sectional survey design with 240 randomly sampled household heads growing maize to examine determinants of adoption of Obatampa varieties (IMVs) by farmers in the Zabzugu-Tatale area in the Northern Reg...