8.2 TCP and UDP as End User Transport Layer Protocols
In Chapter 3, user plane protocol stacks for the mobile network system were presented, showing how end user services are delivered. Due to its simplicity, versatility and efficiency, the TCP/IP protocol suite is now the dominant technology that is used by Internet based applications and services. The high data rate and low latency provided by the evolved radio access systems enable the migration of these services and applications to mobile environments; user traffic over the mobile backhaul is dominantly TCP/IP based.
Popular applications cover a wide range of services with specific QoS requirements such as voice (Skype™), web browsing, web-mail (Gmail™, Yahoo™ mail), instant messaging (MSN™, GoogleTalk™), social networking (Facebook™, MySpace™, LinkedIn™), image and video listing (Flickr™, Picasa™), micro-blogging (Twitter™), video sharing (Youtube™), on-line encyclopedia (Wikipedia™), virtual map and navigation (Google™ Maps), peer-to-peer (BitTorrent™), online gaming (WoW™), on-demand Internet streaming media (Netflix™), Internet radio, etc.
The TCP/IP protocol suite is a four-layer system consisting of the application (HTTP, FTP, e-mail, etc.), transport (TCP, UDP), network (IP, routing protocols, ICMP, etc.) and link layers (Ethernet, etc.). The role of the transport layer is to provide transport service to the application layer above, i.e., a flow of data between two equipments (UEs, UEs and servers, etc.). The two dominant ...