Which of the following is often used for one-to-many communications using broadcast or multicast
IP datagrams?
A.
UDP
B.
FTP
C.
HTTP
D.
SMTP
Explanation:
UDP is often used for one-to-many communications, using broadcast or multicast IP datagrams. User
Datagram Protocol (UDP) is one of the core members of the Internet Protocol Suite, the set of
network protocols used for the Internet. With UDP, computer applications can send messages, in
this case referred to as datagrams, to other hosts on an Internet Protocol (IP) network without
requiring prior communications to set up special transmission channels or data paths. UDP is
sometimes called the Universal Datagram Protocol.Answer D is incorrect. Simple Mail Transfer Protocol (SMTP) is a protocol for sending e-mail
messages between servers. E-mailing systems use this protocol to send mails over the Internet.
SMTP works on the application layer of the TCP/IP or OSI reference model. The SMTP client typically
initiates a Transmission Control Protocol (TCP) connection to the SMTP server on the well-known
port designated for SMTP, port number 25. However, e-mail clients require POP or IMAP to retrieve
mails from e-mail servers.Answer B is incorrect. File Transfer Protocol (FTP) is a standard network protocol used to copy a file
from one host to another over a TCP/IP-based network, such as the Internet. FTP is built on a client-server architecture and utilizes separate control and data connections between the client and server
applications, which solves the problem of different end host configurations (i.e., Operating System,
file names). FTP is used with user-based password authentication or with anonymous user access.Answer C is incorrect. The Hyper Text Transfer protocol is a standard application-level protocol used
to request and transmit files, especially web pages and webpage components, on the World Wide
Web. HTTP runs on top of the TCP/IP protocol. Web browsers are HTTP clients that send file
requests to Web Servers, which in turn handle the requests via an HTTP service.