... one, which indicatesthat channels assigned to the corresponding cells must be distinct, is often referred to as acochannel constraint. An intersite constraint of two, which codifies the requirement ... node or to dif-ferent nodes. More precisely, cirepresents the constraint between nodes at graph distance ifrom each other. The reuse distance of G equals k + 1, the minimum graph distance be-tween ... and P. Spirakis, Frequency assignment in mobile and radionetworks, in Proceedings of the Workshop on Networks in Distributed Computing, DIMACS Se-ries. AMS, 1998. 11. D. A. Fotakis and P....