Abstract:
Proprietary protocol of
ash, RTMFP can be used to share servers' load
by using overlay of peer-to-peer (p2p) connected browsers for streaming.
Hence, huge audience can be entertained using comparatively less server
resources and every new coming client is also considered an addition to
overall system resources. However, RTMFP is not open source and is also
not natively supported in browsers and thus end users need to install Adobe
ash player before using it. It was also built for supporting audio/vedio
streaming and overlay formation for propagation of data is not supported.
Moreover, it works on UDP and thus cannot be used if all UDP ports are
blocked. Although RTMP can be used as fallback option but it follows
the client/server architecture and thus cannot be used to build an overlay
network based on p2p communication. Moreover Adobe has also announced
to cease the development of
ash player for smart phones and is facilitating
the replacement of
ash player with HTML5 features on these devices.
We have focused on mentioned limitations of RTMFP and came up with
a solution which is based on HTML5 standards and thus plugin free in
nature. We have used communication options of HTML5 to implement a
plugin free web based overlay network (WOvNet) and further optimized it
using Battery Status API and Geolocation API of HTML5. Communica-
tion standards of HTML5 includes WebSocket, WebRTC, cross document
messaging and server sent events. WebSocket follows the client/server ar-
chitecture and is doing signalling and maintaining the network topology of
WOvNet, along with server sent events.
DataChannel API of WebRTC is used for data propagation over the
established overlay network and cross document messaging enables the inte-
gration of WOvNet within other applications. Moreover, WebRTC operates
over UDP but can also be con gured to work in scenarios where all UDP
ports are blocked and only 443 port of TCP is available. We have further
improved WOvNet for mobile devices by using adaptive switching of tra c
based on Battery API of HTML5. Link stretch of WOvNet is also reduced
by connecting geographically closer peers and placing these peers in similar
islands or clusters. Geolocation API of HTML5 returns the approximate
geographic locations of peers in longitudes and latitudes and thus helps in
reducing link stretch of WOvNet.
