A Distance Vector Routing Algorithm in Java Printing QR Code in Java A Distance Vector Routing Algorithm 422 A Distance Vector Routing AlgorithmGenerating QR Code In JavaUsing Barcode creator for Java Control to generate, create Quick Response Code image in Java applications.While the LS algorithm is an algorithm using global information, the distance vector (DV) algorithm is iterative, asynchronous, and distributed It is distributed in that each node receives some information from one or more of its directly attached neighbors, performs aMaking Barcode In JavaUsing Barcode generation for Java Control to generate, create barcode image in Java applications.file:///D|/Downloads/Livros/computa o/Computer%20Netown%20Approach%20Featuring%20the%20Internet/algorhtm (4 of 13)20/11/2004 15:52:19Scan Barcode In JavaUsing Barcode reader for Java Control to read, scan read, scan image in Java applications.Point-to-Point Routing Algorithms QR Code 2d Barcode Generation In C#.NETUsing Barcode maker for .NET framework Control to generate, create QR Code ISO/IEC18004 image in Visual Studio .NET applications.calculation, and may then distribute the results of its calculation back to its neighbors It is iterative in that this process continues on until no more information is exchanged between neighbors (Interestingly, we will see that the algorithm is self terminating -- there is no "signal" that the computation should stop; it just stops) The algorithm is asynchronous in that it does not require all of the nodes to operate in lock step with each other We'll see that an asynchronous, iterative, self terminating, distributed algorithm is much more "interesting" and "fun" than a centralized algorithm The principal data structure in the DV algorithm is the distance table maintained at each node Each node's distance table has a row for each destination in the network and a column for each of its directly attached neighbors Consider a node X that is interested in routing to destination Y via its directly attached neighbor Z Node X's distance table entry, Dx(Y,Z) is the sum of the cost of the direct one hop link between X and Z, c(X,Z), plus neighbor Z's currently known minimum cost path from itself (Z) to Y That is: Dx(Y,Z) = c(X,Z) + minw{Dz(Y,w)} (4-1)Drawing Denso QR Bar Code In VS .NETUsing Barcode generation for ASP.NET Control to generate, create QR image in ASP.NET applications.The minw term in equation 4-1 is taken over all of Z's directly attached neighbors (including X, as we shall soon see) Equation 4-1 suggests the form of the neighbor-to-neighbor communication that will take place in the DV algorithm -- each node must know the cost of each of its neighbors minimum cost path to each destination Thus, whenever a node computes a new minimum cost to some destination, it must inform its neighbors of this new minimum cost Before presenting the DV algorithm, let's consider an example that will help clarify the meaning of entries in the distance table Consider the network topology and the distance table shown for node E in Figure 42-3 This is the distance table in node E once the Dv algorithm has converged Let's first look at the row for destination APrint QR In .NETUsing Barcode drawer for .NET framework Control to generate, create QR Code ISO/IEC18004 image in VS .NET applications.Clearly the cost to get to A from E via the direct connection to A has a cost of 1 Hence DE(A,A) = 1 Let's now consider the value of DE(A,D) - the cost to get from E to A, given that the first step along the path is D In this case, the distance table entry is the cost to get from E to D (a cost of 2) plus whatever the minimum cost it is to get from D to A Note that the minimum cost from D to A is 3 -- a path that passes right back through E! Nonetheless, we record the fact that the minimum cost from E to A given that the first step is via D has a cost of 5 We're left, though, with an uneasy feeling that the fact the path from E via D loops back through E may be the source of problems down the road (it will!) Similarly, we find that the distance table entry via neighbor B is DE(A,B) = 14 Note that the cost is not 15 (why )Draw QR Code ISO/IEC18004 In Visual Basic .NETUsing Barcode drawer for .NET Control to generate, create QR Code 2d barcode image in VS .NET applications.Figure 42-3: A distance table example Create GS1 - 12 In JavaUsing Barcode encoder for Java Control to generate, create UPC-A image in Java applications.A circled entry in the distance table gives the cost of the least cost path to the corresponding destination (row) The column with the circled entry identifies the next node along the least cost path to the destination Thus, a node's routing table (which indicates which outgoing link should be used to forward packets to a given destination) is easily constructed from the node's distance table In discussing the distance table entries for node E above, we informally took a global view, knowing the costs of all links in the network The distance vector algorithm we will now present is decentralized and does not use such global information Indeed, the only information a nodePrinting EAN13 In JavaUsing Barcode creation for Java Control to generate, create European Article Number 13 image in Java applications.file:///D|/Downloads/Livros/computa o/Computer%20Netown%20Approach%20Featuring%20the%20Internet/algorhtm (5 of 13)20/11/2004 15:52:19Barcode Generator In JavaUsing Barcode encoder for Java Control to generate, create barcode image in Java applications.Printing EAN / UCC - 14 In JavaUsing Barcode generator for Java Control to generate, create EAN128 image in Java applications.Creating ISSN - 13 In JavaUsing Barcode generation for Java Control to generate, create International Standard Serial Number image in Java applications.UPC-A Supplement 2 Creator In .NETUsing Barcode generator for ASP.NET Control to generate, create GTIN - 12 image in ASP.NET applications.Barcode Generator In .NETUsing Barcode creator for VS .NET Control to generate, create bar code image in VS .NET applications.Print Bar Code In VB.NETUsing Barcode maker for Visual Studio .NET Control to generate, create bar code image in .NET applications.