TCP/IP （ ）layer protocols provide services to the application（ ）running on a computer. The application layer does not define the application itself, but rather it defines（ ）that applications need--like the ability to transfer a file in the case of HTTP. In short, the application layer provides an（请作答此空）between software running on a computer and the network itself. The TCP/IP application layer includes a relatively large number of protocols, with HTTP being only one of those. The TCP/IP（ ）layer consists of two main protocol options--the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP).

A iteration

B object

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D activity