Patent ID: 7113506

Claim:
A network comprising: a plurality of switches, each switch having two X ports and two Y ports; wherein: each switch in said plurality is associated with a label <c; r> based on position in a two dimensional array, with c indicating a level number in a range 0 through i through n, each level having N=2 n switches, and r indicating a row number in a range 0 through N−1, the row number being an n-bit number in binary having bits r 0 r 1 . . . r(n−1) and “. . . ” between any two bits ri and rj indicating: a single bit if j=i+1, or several additional bits if j>i+1, unless j=i in which case range ri . . . rj indicates a single bit; said each switch labeled <c; r> has a first X port connected by a first wire to a first Y port of a switch labeled <c−1; r>; said each switch labeled <c; r> has a first Y port connected by a second wire to a first X port of a switch labeled <c+1; r>; said each switch labeled <c; r> has a second X port connected by a third wire to a first Y port of a switch labeled <c−1; s>, with all bits si=ri except for one bit sh=1−rh, h being in the range 0 through n−1; said each switch labeled <c; r> has a second Y port connected by a fourth wire to a first X port of a switch labeled <c+1; t>, with all bits ti=ri except for one bit tk=1−rk, k being in the range 0 through n−1; said plurality of switches comprises a first group of switches and a second group of switches; at least one switch of said first group of switches is set to configure a first path; at least one switch of said second group of switches is set to configure a second path; a first switch in said plurality of switches is coupled to a second switch in said plurality of switches by said first path; said first switch is coupled to a third switch in said plurality of switches by said second path; each switch in said second group of switches is absent from said first group of switches, so that said first path is node disjoint relative to said second path; each of c, r, s, and t is a non-negative integer; said first group of switches includes at least one of said plurality of switches associated with a first label selected from a first list of labels; and said second group of switches includes at least one of said plurality of switches associated with a second label selected from a second list of labels.