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Roberto Riggio edited this page May 8, 2016 · 13 revisions

WING - Wireless Mesh Network for Next-Generation Internet

WING started as a 3 years research project on Wireless Mesh Networks, sponsored by the Italian Ministry of University and Research and led by CREATE-NET and Technion. The project aimed at fostering the scientific cooperation between CREATE-NET and the Technion through the creation of a top-level international research team in the area of algorithms and protocols for wireless networking, able to stay at the forefront of technological and scientific research through the integration of the different competences owned by the two proposing institutions.

Part of the developed software is built on top of Roofnet, an experimental 802.11b/g mesh network developed by the MIT CSAIL. WING extends the original project by adding support for multiple radio interfaces, WCETT routing metric, and autonomic channel assignment. All the developed software modules have been released under a BSD License and are made fully available to the research community.

The following picture sketches the overall wireless mesh router architecture.

Architecture

As it can be seen from the picture, the node supports multiple backhauling technologies (Wired, WiFi, and UMTS). The software can seamlessly switch from one backhaul link the the other. However, due to the use of Network Address Translation (NAT) techniques at the mesh gateway, existing connections exploiting statefull protocols, such as TCP, are terminated when the backhaul link is switched. Routing software is implemented using the Click modular router.

Using Wing

  • Downloads: all the software released by the Wing-Project
  • OpenWRT: How to build and run WING on an embedded platform using OpenWRT.
  • Desktop: How to build and run Wing on a generic Linux machine (e.g. your laptop). You will need a set a PCs each of them equipped with a WiFi card supported by the madwifi driver.

Research directions

  • Adaptive traffic aggregation: A packet concatenation scheme capable of boosting the voice capacity of the network.

  • Opportunistic scheduling: An opportunistic scheduler addressing the IEEE 802.11 performance anomaly.

  • QoS Provisioning: A DiffServ framework providing soft QoS bounds over wireless mesh networks.

  • TBMGA: Tree-Based Routing in Multi-Gateway-Association based Wireless Mesh Networks.

  • Channel-assignment: An interference and traffic aware channel assignment (ITACA) scheme.

  • Power Consumption: A Distributed Energy Consumption Monitor for Wireless Networks.

  • Publications: Papers describing the achieved results.

Features

Multi-radio support

Multiple radio interfaces support delivers improved spatial reuse and enhanced system throughput. An interference and traffic aware channel assignment algorithm is used in order to dynamically assign the operating frequencies.

Auto-configuration

WING nodes can automatically detect if they are relays or gateways. The node auto-configures itself as gateway if an IP address can be obtained using DHCP over one the supported uplink backends. Currently the following uplink technologies are supported:

  • Wired, Ethernet. The eth0 interface is the default uplink technology used by the WING nodes. Power-over-Ethernet is supported for streamlined outdoor deployment.

  • Wireless, IEEE 802.11. In dual radio setups the second wireless interface can be configured in client mode and used to implement a three tiers architecture. Some manual intervention may be required in order to configured the network SSID and the WPA/WEP key.

  • Wireless, UMTS. On boards equipped with a UMTS/CDMA modem a 3G network can be used as uplink technology. At the moment only the Huawei E169 UMTS Modem (USB interface) is supported. Some manual configuration may be required in order to configure the provider specific parameters.

Three-tiers architecture

Internet connectivity is provided by the Mesh Gateways using either wired or wireless links. This is useful in three-tiers architectures where the gateways are connected to a bandwidth aggregation point using point-to-multipoint wireless links, Currently supported technologies are: WiFi, WiMax, and UMTS.

QoS Support

WING implements several QoS enhancements aimed at improving the voice capacity of the system and at providing performance isolation among competing flows in noisy environments. Traffic differentiation is provided by means of a multi-queue system based on the DiffServ framework. The Per-Hop Behavior (PHB) must be specified by the source by encoding a 6-bit value—called the Differentiated Services Code Point (DSCP)—into the 8-bit Differentiated Services (DS) field of the IP packet header. The following treatment is then applied by the mesh routers:

DSCP (decimal) PHB Weights Description Applications
0 Default 1 opportunistic link scheduling Any
10 AF21 2 Traffic aggregation and opportunistic link scheduling (non delay-sensitive) Streaming
34 AF41 4 Traffic aggregation and opportunistic link scheduling (delay sensitive) VoIP

Scenarios

  • Increased coverage in outdoor WiMAX networks. An hybrid WiMAX/Wi-Fi mesh architecture can decrease the number of WiMAX base stations needed to obtain good coverage.

  • Reduced dead zones in Enterprise Indoor Wi-Fi networks. A hybrid WiMAX/WiFi mesh architecture can provide ubiquitous indoor coverage for office/business environments.

  • Embedded CPE. WING imposes no additional hardware/software requirements on the client-side, making it possible to leverage the entire WiFi installed base. In dual-interface setups, the second wireless interface can be configured to serve a standard WiFi Access Point providing end-user with Internet connectivity.

  • Fast provisioning. The self-configuring mesh backhaul allows for drop-in network coverage only when/where needed. In case of a fully outdoor deployment, no additional equipment needs to be installed on the end-user side. WING is an excellent plug-in solution in existing and less reliable WiFi deployments.

  • Embedded VoIP service. WING supports out of the box VoIP functionalities that can be exploited by the end-users using any VoIP client (mobile handsets with WiFi capabilities are also supported, e.g., Nokia E-Series, RIM Blackberry, and Apples iPhone).