Codes for Networkcoding A constant dimension code with parameters n, k, d and q is a collection of k-dimensional subspaces of the n-dimensional vector space \(GF(q)^n\) over a finite field with q elements, called codewords, such that the dimension of the intersection of each pair of different k-dimensional subspaces is at most \(k-d/2\). Let \(A_q(n,d;k)\) denote the maximum number of codewords. For instance cdc6-4-3-2 \(A_2(6,4;3)=77\) is known , while \(333 \le A_2(7,4;3) \le 381\) for instance cdc7-4-3-2 are the tightest known bounds, see e.g. . A code of size 381 would correspond to a putative binary q-analog of the Fano plane (finite projective plane of order 2 with 7 points and lines). More bounds are available at http://subspacecodes.uni-bayreuth.de.