I am using MAC book(IOS version 11.4) and connect to the same AP with IFP6550, but I can't find IFP6550 via Airplay, how can I do?

You need to power off then on the AP and reset it.

What version of HDMI does a consumer need to view 1080p content?

HDMI has always supported 1080p resolution, starting from version 1.0 in 2002. However, as with many functions that HDMI enables (such as DVD-Audio and SACD), it is up to the manufacturer to choose whether to implement 1080p in the device. Some TV and device manufacturers have chosen not to implement 1080p in their products because 1080p conte...

Does HDMI accommodate long cable lengths?

HDMI technology has been designed to use standard copper cable construction at long lengths.  In order to allow cable manufacturers to improve their products through the use of new technologies, HDMI specifies the required performance of a cable but does not specify a maximum cable length.  HDMI Org. have seen cables pass "Standard Cable" HDM...