TCP, on the other hand, offers several additional services to applications. First
and foremost, it provides reliable data transfer. Using flow control, sequence numbers, acknowledgments, and timers (techniques we’ll explore in detail in this chapter), TCP ensures that data is delivered from sending process to receiving process,
correctly and in order. TCP thus converts IP’s unreliable service between end systems into a reliable data transport service between processes. TCP also provides
congestion control. Congestion control is not so much a service provided to the
invoking application as it is a service for the Internet as a whole, a service for the
general good. Loosely speaking, TCP congestion control prevents any one TCP connection from swamping the links and routers between communicating hosts with an
excessive amount of traffic. TCP strives to give each connection traversing a congested link an equal share of the link bandwidth. This is done by regulating the rate
at which the sending sides of TCP connections can send traffic into the network.
UDP traffic, on the other hand, is unregulated. An application using UDP transport
can send at any rate it pleases, for as long as it pleases.
TCP, on the other hand, offers several additional services to applications. Firstand foremost, it provides reliable data transfer. Using flow control, sequence numbers, acknowledgments, and timers (techniques we’ll explore in detail in this chapter), TCP ensures that data is delivered from sending process to receiving process,correctly and in order. TCP thus converts IP’s unreliable service between end systems into a reliable data transport service between processes. TCP also providescongestion control. Congestion control is not so much a service provided to theinvoking application as it is a service for the Internet as a whole, a service for thegeneral good. Loosely speaking, TCP congestion control prevents any one TCP connection from swamping the links and routers between communicating hosts with anexcessive amount of traffic. TCP strives to give each connection traversing a congested link an equal share of the link bandwidth. This is done by regulating the rateat which the sending sides of TCP connections can send traffic into the network.UDP traffic, on the other hand, is unregulated. An application using UDP transportcan send at any rate it pleases, for as long as it pleases.
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