1. TANGO TANGO ALTERNATE NETWORK GRAPH ORGANIZER Olof Hellqvist Zak Blacher

2. Agenda Introduction Net-X System eXtensions OLSRd Overview Channel Changer (CHACHA) Tango o Overview o Server o Protocol o Client Demo Future work Thanks / Questions

3. Introduction Project description: Our assignment was to build a centralized channel assignment framework for wireless mesh networks that interacted with the current distributed channel assignment plugin for olsr CHACHA

4. Net-X System eXtensions Net-X is a Linux-based software framework for multi-channel/multi-radio wireless mesh networks Consist of o A routing layer o A channel abstraction layer o A modified Network interface card (NIC) driver Layer 2.5

5. OLSRd Overview Implements Optimized Link State Routing Protocol Deployed on large scale ad-hoc networks o i.e. mesh networks o NOT for sensor networks Proactive Protocol - distributes routing information in advance.

6. CHAnnel CHAnger Distributed algorithm for assigning channel for the fixed interface. Replaces the HelloServer in the Optimized Link State Routing Protocol. The HelloServer balance the use of the channels for the fixed interfaces on the nodes in the mesh network. Broadcasts channel information to all one- and two- hop neighbours.

7. TANGO Overview Tango Alternate Network Graph Organizer Centralized Channel Assignment Framework For Wireless Mesh Networks

8. TANGO Server Extendable C++ implementation Reads and santity checks current configuration stored in libconfig configuration syntax.

9. TANGO Server configuration file config.cfg: version = "1.0"; tango = ({ ip = "192.168.30.7"; channel="40"; }, { ip = "192.168.30.21"; channel="64"; }, { ip = "192.168.30.22"; channel="44"; }); ip = "192.168.31.200"; port = 50000; ###eof Tango servers utilizes libconfig => configuration file is written in libconfig syntax

10. TANGO Protocol TCP based clear text protocol Clients pull the there current fixed channel The server will return either the new fixed channel or -1 depending on if the node exist in the current configuration

11. TANGO Client Extension of CHACHA (replaced least_used_channel) Periodically updates the channel for the fixed interface. (polling)

12. DEMO

13. Future work Expand tango server with routing algorithm (they can either generate configuration files or be embedded in the server). Replace the TCP communication with olsr- messages Add feedback information from the client in order to make more a intelligent routing intelligent channel choice depending on the nodes environment. Expand the configuration options of the server (e.g. channels different standards).

14. for listening

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