An optical fiber link, comprising: a first optical fiber having a glass core which supports the propagation and transmission of an optical signal with X LP modes at a wavelength of 1550 nm, wherein X is an integer greater than 1 and less than or equal to 20, said optical fiber having a positive differential mode group delay between the LP01 and LP11 modes at a wavelength between 1530-1570 nm; and a second optical fiber having a glass core which supports the propagation and transmission of an optical signal with Y LP modes at the wavelength of 1550 nm, wherein Y is an integer greater than 1 and less than or equal to 20, said optical fiber having a negative differential mode group delay between the LP01 and LP11 modes at a wavelength between 1530-1570 nm; wherein the glass core of said first and second fibers (11,12) has a radius R 1 in the range from 8 μm to 20 μm, and the first and second fibers further comprise an inner cladding, a low index trench region and a glass outer cladding, the glass outer cladding surrounding the glass core, the inner cladding and the low index trench region; wherein the low index trench region has an index difference Δ 2 relative to the glass outer cladding of between -0.1 % and -0.7 % and a radial thickness between 2 μm to 8 μm; wherein said first and second fibers (11,12) comprise a graded refractive index core profile with an alpha value greater than or equal to 1.5 and less than 3.0 at the wavelength of 1550 nm, a maximum relative refractive index Δ 1MAX in the range from 0.3% to 0.6% relative to said glass outer cladding, and an effective area at 1550 nm greater than 120 μm 2 and less than 240 μm 2; and wherein said alpha value curvature of said first fiber is α 1, and said alpha value curvature of said second fiber is α 2, and |α 1 - α 2 | > 0.2 and wherein the lengths of the first and second fibers are selected to result in an absolute value of differential group delay between the LP01 and LP11 modes over the link that is less than 0.5 ns/km at the wavelength of 1550 nm. a first optical fiber having a glass core which supports the propagation and transmission of an optical signal with X LP modes at a wavelength of 1550 nm, wherein X is an integer greater than 1 and less than or equal to 20, said optical fiber having a positive differential mode group delay between the LP01 and LP11 modes at a wavelength between 1530-1570 nm; and a second optical fiber having a glass core which supports the propagation and transmission of an optical signal with Y LP modes at the wavelength of 1550 nm, wherein Y is an integer greater than 1 and less than or equal to 20, said optical fiber having a negative differential mode group delay between the LP01 and LP11 modes at a wavelength between 1530-1570 nm; wherein the glass core of said first and second fibers (11,12) has a radius R 1 in the range from 8 μm to 20 μm, and the first and second fibers further comprise an inner cladding, a low index trench region and a glass outer cladding, the glass outer cladding surrounding the glass core, the inner cladding and the low index trench region; wherein the low index trench region has an index difference Δ 2 relative to the glass outer cladding of between -0.1 % and -0.7 % and a radial thickness between 2 μm to 8 μm; wherein said first and second fibers (11,12) comprise a graded refractive index core profile with an alpha value greater than or equal to 1.5 and less than 3.0 at the wavelength of 1550 nm, a maximum relative refractive index Δ 1MAX in the range from 0.3% to 0.6% relative to said glass outer cladding, and an effective area at 1550 nm greater than 120 μm 2 and less than 240 μm 2; and wherein said alpha value curvature of said first fiber is α 1, and said alpha value curvature of said second fiber is α 2, and |α 1 - α 2 | > 0.2 and wherein the lengths of the first and second fibers are selected to result in an absolute value of differential group delay between the LP01 and LP11 modes over the link that is less than 0.5 ns/km at the wavelength of 1550 nm.