Virtual Private Network System Research Articles

BUILDING A LINUX-BASED VPN SERVER USING POINT TO POINT TUNNELING PROTOCOL (PPTP)

Virtual Private Network (VPN) technology has an important role in today's world of communication, VPNs are able to create local networks using facilities. Because a corporate VPN can make connecting information easy and secure. But nowadays, VPNs are gaining popularity for personal use due to the increasing number of interactions that require users to surf the web. On a VPN system that uses the Point to Point Tunneling Tradition (PPTP) method that we created, we use a server from Linux that will connect to Windows as a user. So that clients or windows can connect to the web using a VPN server from linux.
 

Construction of a VPN System for Remote Programming and Monitoring of Environmental Parameters for Serving Plant Production in Greenhouses

This article introduces a virtual private network (VPN) system deployed in a 70m2 operator station and greenhouse at Vietnam National University of Agriculture. The VPN system was not limited by geographical distance and allowed for remote monitoring of environmental parameters, viz. light (10-16000lux), soil moisture (20-100%), temperature (20-60oC), and ambient humidity (30-90%) with tolerances of ± 5% of the set/measured values. The signals from the sensor system were recorded with a sampling time of 6 seconds. The designed interface made it easy for Vietnamese users. The system was initially established, and tested successfully with Gerbera in the greenhouse. The VPN system allowed for remote programming, stable operation, and no loss of data during the signal collecting process, and allowed users to fully and quickly react when the system crashed or when the user needed to upgrade or maintain the greenhouse system.

All-optical VPN utilizing DSP-based digital orthogonal filters access for PONs

Utilizing digital filtering-enabled signal multiplexing and de-multiplexing, a cost-effective all-optical virtual private network (VPN) system is proposed, for the first time to our best knowledge, in digital filter multiple access passive optical networks (DFMA-PONs). Based on the DFMA technology, the proposed system can be easily designed to meet the requirements of next generation network’s flexibility, elasticity, adaptability and compatibility. Through dynamic digital filter allocation and recycling, the proposed all-optical VPN system can provide dynamic establishments and cancellations of multiple VPN communications with arbitrary traffic volumes. More importantly, due to the employment of DFMA technology, the system is not limited to a fixed signal format and different signal formats such as pulse amplitude modulation (PAM), quadrature amplitude modulation (QAM) and orthogonal frequency division multiplexing (OFDM) can be used. Moreover, one transceiver is sufficient to simultaneously transmit upstream (US)/VPN data to optical line terminal (OLT) or other VPN optical network units (ONUs), thus leading to great reduction in network constructions and operation expenditures. The proposed all-optical VPN system is demonstrated with the transceiver incorporating the formats of QAM and OFDM, which can be made transparent to downstream (DS), US and VPN communications. The bit error rates (BERs) of DS, US and VPN for OFDM signals are below the forward-error-correction (FEC) limit of 3.8×10−3 when the received optical powers are about −16.8 dBm, −14.5 dBm and −15.7 dBm, respectively.

All-Optical Virtual Private Network in OFDM-PON Using Microwave Photonic Filter

We propose and demonstrate a novel all-optical virtual private network (VPN) using a microwave photonic filter, which enables inter-communications among optical network units in a passive optical network system. In our scheme, an optical coupler based recirculating delay line is used at optical line terminal as an optical subsystem to implement a microwave photonic-bandpass filter (MP-BPF). The periodic passbands of an MP-BPF are used to transmit VPN signal, whereas stopbands are used for conventional upstream transmission. The proposed system has two critical issues, optical phase-induced intensity noise in the MP-BPF and Rayleigh back-scattering interference by a single-fiber loop back link. To overcome the issues, an RF clipping tone based spectrum-broadening technique is applied to uplink transmitter. The proposed all-optical VPN system is tolerant to wavelength of VPN optical carrier, and enables multi-VPN data transmission using multi-passbands of MP-BPF.

Geographically Secured SSL-VPN Using GPS

are moving towards an era where location information will be necessary for access control. The use of location information can be used for enhancing the security of an application, for critical applications, such as the military. A formal model for location-based access control is needed that increases the security of the application and ensures that the location information cannot be exploited to cause harm. In this paper, we show how the SSL VPN model can be extended to incorporate the notion of location. We show how this location information can be used to determine whether a subject has access to a given object. A novel improved VPN (Virtual Private Network) system based on geo-secured SSL (Secure Socket Layer) protocol is proposed to overwhelm the defects of traditional SSL VPN. It enhances current security applications granting access to sensible information and privileges to execute orders only to entities that are in a trusted location. This system not only authenticates authorized user but also the location of the user

Qualitative and quantitative assessment of video transmitted by DVTS (digital video transport system) in surgical telemedicine

Real-time video pictures can be transmitted inexpensively via a broadband connection using the DVTS (digital video transport system). However, the degradation of video pictures transmitted by DVTS has not been sufficiently evaluated. We examined the application of DVTS to remote consultation by using images of laparoscopic and endoscopic surgeries. A subjective assessment by the double stimulus continuous quality scale (DSCQS) method of the transmitted video pictures was carried out by eight doctors. Three of the four video recordings were assessed as being transmitted with no degradation in quality. None of the doctors noticed any degradation in the images due to encryption by the VPN (virtual private network) system. We also used an automatic picture quality assessment system to make an objective assessment of the same images. The objective DSCQS values were similar to the subjective ones. We conclude that although the quality of video pictures transmitted by the DVTS was slightly reduced, they were useful for clinical purposes. Encryption with a VPN did not degrade image quality.

A network-based VPN architecture using virtual routing

A network-based Virtual Private Network (VPN) architecture by using fundamental routing mechanism is proposed. This network is a virtual overlay network based on the relay of IP-in-IP tunneling of virtual routing modules. The packet format employs the encapsulation of IPSec ESP (Encapsulating Security Payload), an impact path code and an extended DS (Differentiated Services) code to support multi-path routing and QoS. Comparing with other models of VPN, this network system can be deployed in the current network with little investment, and it is easy to implement. The simulation result shows its performance is better than the traditional VPN system of black box mode.