Have you given up on LiNK like I almost did? Have you done everything and it still does not work? Well this thread is a list to display compatible and non-compatible LiNK routers as the router actually can prevent you from playing on LiNK even if all results are a pass. For example, you will get the dreaded "Unable to join game session" on Black Ops 2.
1) Asus RT-N56U (Tested with ports 1003 and 1004) (You must port forward for LiNK to work with UPNP enabled, works with ethernet and wifi)
2) TP-Link WDR-3600 with OpenWRT installed, used with UPNP enabled works with both ethernet and Wifi
3) Netgear DG834 & N300 using ethernet
1) All technicolor routers (from Telstra in Australia)
Kindly post compatible and non-compatible routers so that we can add to this list and assist other potential LiNK users. Also post whether you needed to port forward or it worked without port forwarding. Additionally, post whether it works with ethernet, wifi or both.