MultiNet: connecting to multiple IEEE 802.11 networks using a single wireless card

Abstract

There are a nuniher of scenarios where it is desirable to have a wireless device connect to multiple networks simullaneowly. Currently, this i5 possible only hy using multiple wireleqs network cards in the device. Unfortunately, using nwltiple wireless cards causes excessive energy drain and consequent reduction of lifetime in hattery operated devices. In this paper, we prnpose a software hased approach, called MultiNet, that facilitates simultaneous connections to multiple networks hy virtualizini a single wireless card. The wireless card is virtualized hy : introducing an intermediate layer helow IP. which continuously switches the card acrms multiple networks. Tlie~ goal o f the switching algorithm is to he transparent to the user who see5 her machine as heing connected to multiple networks. We preent the design, implenientation, and perforninnce of the MnltiNet system. We analyze and evaluate hnWring and sritching algorithnis in terms of delay and energy consumption. Our system is agnostic of the upper layer protocols, and works well over popular IEEE !3002.11 wireless LAN cards. IXTRODUCTIONThere are several papers that articulate the. benefits of virtudimion 141. [71. [151. However. to the hest of our knowledge. the benefits of virtualizing a wireless card has been overlooked. In this paper. we propose MultiNet. a new virtualization architecture that absuacts'a single wireless LAN (WLAN) card to appear as multiple virtual cards to the user. MultiNet allows these virtual cards to be simultaneously connected to physically different wireless networks. We describe our architecture in detail and then present a buffering protocol and two switching algorithms that give good performance for many common applications. such as telnet. ftp. file sharing Our. research is motivated by several compelling~scenarios that are enabled with the above functionality. These scenarios include: increased connectivity for end users; increased range of the wireless network: bridging between infrastructure and ad hoc wireless networks. and painless secure access to sensitive resources. We discuss these in detail in Section 11.To enable these scenarios with current technology. one has to use a single WLAN card for each desired network. However. this is costly. cumbersome. and consumes energy resources that are often limited. An alternative to using more hardware -and web downloads.-. .. is to use MultiNet and its accompanying protocols. MultiNet requires changes to the data link or device driver layer o f the networking stack. It creates and manages multiple network stacks and maintains the associated state information for each network that the card is connected to. Simultaneous connectivity over all networks is achieved by switching the card hetween the desired networks and activating the corresponding stack.An advantage of this architecture is that it allows applications and protocols like TCP/IP to work without any changes.In this paper we make the following four research contributions:. We present a new architecture for virtualizi...

PS-Net : Personalized Secure Wi-Fi Networks

“…초 기에 사용되던 WEP(Wired Equivalent Privacy) 기술 에 보안 취약성이 발견되어 WPA(Wi-Fi Protected Access)가 개발되었고 다시 WPA2로 발전되었다 [5,6] . [7] .…”

Optimal File Splitting for Wireless Networks with Concurrent Access

“…Various approaches have appeared to exploit multiple transmission paths in parallel. For example by using multi-element antennas, as adopted by the IEEE802.11n draft [4] standard, at the physical layer or by switching datagrams at the link layer [3,8], and also by using multiple TCP sessions in parallel to a file-server [20]. In the latter case each available network transports part of the requested data in a separate TCP session.…”

How to Effectively Use Multiple Channels in Wireless Mesh Networks

“…Chandra et al [14] study the concept of switching delay between multiple channels using only one 802.11 NIC through a software-based approach. They observe a delay of 3.9 seconds when switching from an infrastructure network to an ad hoc network and a delay of 2.8 seconds when switching from an ad hoc network to an infrastructure network.…”

“…Besides, the experiments in [14] and [30] are carried out with the use of laptops, while in our experiment, wireless routers, which have different software and hardware from laptops, are used because this is the case in WMNs.…”