Actually Line 6 recommends a standard XLR: http://line6.com/l6link/ :)
"What kind of cable does L6 LINK use?
L6 LINK works with a standard XLR cable. Because the quality and manufacturing processes of XLR cables vary widely, we can’t guarantee the performance of any particular XLR cable. However, if you are looking for a cable to use with L6 LINK, we recommend the Classic Series Microphone Cable (25 ft.) from Planet Waves, which was among the best we tested."