In Tabu algorithm, we initialize by randomly assigning the channels to links. The channel for each link is selected randomly from the set of K available channels. This assignment is done without taking radio constraints into account. Then we try to improve the assignment in each iteration. For this, we prepare r new assignments; each being different from the original by one link channel assignment. These r assignments are then compared to find the one that reduces the interference the most. This assignment is then chosen as the next base case from which r different assignments are prepared. To escape the local minima, the assignment chosen between the r may have greater interference than the original base case. We terminate the algorithm when we cannot find any improvement in the best case (saved separately from the base case) for the |E| number of iterations. To speed up things, we maintain a Tabu list of limited size in which we guard the solution selected from the r assignment in each iteration. Before calculating a new solution, we check if this solution is already present in the Tabu list. If it is, then we don't need to select the same solution again. When the first phase terminates, we have a channel assignment that minimizes the interference. But this assignment does not respect the radio constraint that must be followed at each node. We now apply a procedure which makes this assignment respect the constraints of limited radios at each node. Here we first select a node with maximum violations, i.e. a node that uses the maximum number of channels and has the maximum connections. In case of a tie, we randomly select the node. Then we select two channels being used by the node and merge the two channels into one channel. The channels are selected such that their merging causes the minimum of interference increase. Since the nodes may be using the same channel to connect with other nodes as well, which may be connected to other nodes and so on, hence the merging of channels is propagated to all connected nodes in the network using the channels. Thus a merge iteration, decreases the conflict for all nodes in the network and does not
cause any conflict increase at any node. We continue suchmerge operations until no node in the assignment violates the radio constraints. From the above description it is clear that the Tabu algorithm unlike random or clica is not a one pass algorithm. Also, the computational time of tabu algorithm is large as we have to prepare r solutions (we have taken r = V/2; where V is the number of vertices in the reachability graph) and calculate the total interference of each solution, from which one is selected in each iteration. Also, we have a minimum of |E| = Vc iterations (|E|=number of links in the network).
http://168forums.com/index.php?action=profile;u=35802
http://apocalyptotuesday.com/profile.php?mode=viewprofile&u=115166
http://bobesman.6.forumer.com/profile.php?mode=viewprofile&u=112772
http://edutekne.com.ar/foro1/profile.php?mode=viewprofile&u=25228
http://foro.fochesatosport.com/index.php?topic=25225.new#new
http://forum.daplugin.com/index.php?action=profile;u=68431
http://forum.kampuszede.com/profile.php?mode=viewprofile&u=5276
http://forum.pokemon.no/profile.php?id=70806
http://forum.spanesi.com/index.php?action=profile;u=24956
http://heroesinthesky-forum.gamigo.de/member.php?u=31004
http://hidoshi.com/forum/index.php?action=profile;u=102529
http://hochampcar.com/smf/index.php?action=profile;u=83795
http://ispyfletch.com/forum/index.php?action=profile;u=24741
http://jackd.notumco.ws/profile.php?mode=viewprofile&u=45535
http://jerrytomson.com/index.php?showtopic=38677
http://make-money-blogging-tips.blogthistothebank.com/index.php?action=profile;u=17493
http://neighborvillage.net/index.php?topic=165598.new#new
http://oralnerveinjuries.com/forum/index.php?topic=11523.new#new
http://rp-asylum.com/index.php?action=profile;u=21303
http://s2rgroup.com/simplemachinesforum/index.php?action=profile;u=28797
http://soflaneighborhoods.com/index.php?topic=519698.new#new
http://technoportsolutions.com/forum/profile.php?mode=viewprofile&u=71837
http://untc.cv/forum/index.php?action=profile;u=21316
http://www.advhive.com/forum/index.php?action=profile;u=35938
http://www.cine-web.com/smf/index.php?topic=50214.new#new
http://www.cumberlandraiders.com/forum/index.php?action=profile;u=74610
http://www.diariolainfo.com/foro/index.php?action=profile;u=26123
http://www.diportima.com/foro/index.php?action=profile;u=62602
http://www.exotically.com/profile.php?mode=viewprofile&u=138904
http://www.fordj.com.pl/profile.php?mode=viewprofile&u=48001
http://www.freereviewscript.com/forum/index.php?action=profile;u=12794
http://www.hi-qc.com/board/index.php?topic=171754.new#new
http://www.opinionconsumidor.es/index.php/topic,15445.new.html#new
http://www.seriestugas.com/index.php?action=profile;u=42795
http://www.thaipropertytalk.com/index.php?action=profile;u=17245
http://www.torgeir-bjelland.com/forum/index.php?action=profile;u=19586
