It provides a snapshot of the current performance of our global IP backbone (AS 6762).This looking glass is here as a courtesy and should only be used to verify reachability. In fact, as the ICMP traffic is handled on routers with low-priority, this tool has not to be intended for use in measuring SLAs.
All ping and traceroutes towards Sprint (AS 1239) and DTAG (AS 3320) backbones originating on a router where they are directly connected will not work because they do not redistribute the point-to-point addresses in their routing. It's their policy and there is no point in complaining. In some cases it is possible that the traceroute works but the return path is unexpectedly much longer due to different routing. Please use a different origin router and everything will just work.