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Arrive AirPoint
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- Network Deployment Guide
How AirPlay mirroring works
Figure 13: Apple AirPlay mirroring with Arrive MediaPoint
AirPlay and AirPlay Mirroring are two separate elements of Apple’s streaming system.
AirPlay Mirroring is different than AirPlay in a number of areas. AirPlay Mirroring establishes
a video stream based on the H.246 video format that is continuously being streamed to the
Arrive AirPoint device box (and sent to the TV screen). This H.246 stream is created inside
the graphic card at the same time as the video stream for the actual iOS screen is created,
and that is why AirPlay Mirroring only works on newer Apple devices. What is important to
understand is that this approach enables the video stream to be streamed directly to the
Arrive AirPoint device with minimal delay. When connected to a WiFi network, the Apple
device also gets Internet access while streaming the media, however, the performance
is limited by the capability of the WiFi infrastructure. Again, the faster the WiFi network,
the better, as WiFi reliability is actually the real bottleneck here. Unlike Miracast, Apple
AirPlay does not support WiFi Direct, the reliance on the WiFi network for screen mirroring
performance is enhanced. Miracast reduces this dependence by making dual connections
from the devices.
10. About Miracast
Miracast is a certification program of the WiFi Alliance based on their Wifi-Display
specification. It defines a protocol to connect an external monitor or TV to a device, and
therefore can roughly be described as “HDMI over WiFi”, replacing the cable from the
computer to the display.