5 Transport Protocols: TCP and UDP Free Online FlashCards

What does the transport layer enable?

The transport layer lets programs on different hosts communicate, using network-layer delivery and adding services such as application addressing and delivery management.

What does a transport-layer port identify?

A port number identifies an application endpoint on a host, while an IP address identifies a host or network interface for delivery.

What range of port numbers does each of TCP and UDP support?

TCP and UDP each have a separate 16-bit port space, ranging from 0 to 65,535.

What is transport-layer multiplexing?

Multiplexing combines outgoing data from different applications so it can share the network.

What is transport-layer demultiplexing?

Demultiplexing directs incoming data to the appropriate application using transport information such as protocol and port numbers.

How does TCP establish communication between endpoints?

TCP is connection-oriented: endpoints establish a connection before exchanging data and close it when finished.

What data model does TCP present to applications?

TCP presents a continuous byte stream, not separate messages. An application protocol must define how to identify message boundaries.

How does TCP provide reliable, ordered delivery?

TCP uses sequence numbers, acknowledgments, and checksums, and retransmits lost data to provide reliable, in-order delivery. This suits file transfer, where missing bytes matter.

What problem does TCP flow control address?

TCP flow control helps prevent a sender from overwhelming the receiving endpoint.

What problem does TCP congestion control address?

TCP congestion control helps limit traffic when the network path is overloaded.

What data model does UDP provide?

UDP sends independent datagrams and preserves their message boundaries.

What delivery guarantees does UDP provide by itself?

UDP does not guarantee that a datagram will arrive, arrive only once, or arrive in order.