auth.gfx.ms is an alias for authgfx.msa.akadns6.net.
authgfx.msa.akadns6.net is an alias for msagfx.live.com-6.edgekey.net.
msagfx.live.com-6.edgekey.net is an alias for e13551.dscg.akamaiedge.net.
e13551.dscg.akamaiedge.net has address 92.123.167.207