Diameters of distance graphs in pseudoeuclidean spaces

N this article, we consider a generalisation of distance graph in pseudoeuclidean spaces Rr,s and Qr,s to scalar product derived from the quadratic form Ir,s(x1,..., xr+s) = х21 + ... + х2r - х2r+1 - ... - x2r+s. We study diameters of these graphs and show that they are finite and at most 5. We also find exact values of the case r = s = 1.