Which of the following is a standard protocol for interfacing external application software with an
information server, commonly a Web server?

A.
DHCP

B.
IP

C.
CGI

D.
TCP

Explanation:

The Common Gateway Interface (CGI) is a standard protocol for interfacing external application
software with an information server, commonly a Web server. The task of such an information
server is to respond to requests (in the case of web servers, requests from client web browsers)
by returning output. When a user requests the name of an entry, the server will retrieve the source
of that entry’s page (if one exists), transform it into HTML, and send the result.
Answer option A is incorrect. DHCP is a Dynamic Host Configuration Protocol that allocates
unique (IP) addresses dynamically so that they can be used when no longer needed. A DHCP
server is set up in a DHCP environment with the appropriate configuration parameters for the
given network. The key parameters include the range or “pool” of available IP addresses, correct
subnet masks, gateway, and name server addresses.
Answer option B is incorrect. The Internet Protocol (IP) is a protocol used for communicating data
across a packet-switched inter-network using the Internet Protocol Suite, also referred to as
TCP/IP.IP is the primary protocol in the Internet Layer of the Internet Protocol Suite and has the
task of delivering distinguished protocol datagrams (packets) from the source host to the
destination host solely based on their addresses. For this purpose, the Internet Protocol defines
addressing methods and structures for datagram encapsulation. The first major version of
addressing structure, now referred to as Internet Protocol Version 4 (IPv4), is still the dominant
protocol of the Internet, although the successor, Internet Protocol Version 6 (IPv6), is being
deployed actively worldwide.
Answer option D is incorrect. Transmission Control Protocol (TCP) is a reliable, connectionoriented protocol operating at the transport layer of the OSI model. It provides a reliable packet
delivery service encapsulated within the Internet Protocol (IP). TCP guarantees the delivery of
packets, ensures proper sequencing of data, and provides a checksum feature that validates both
the packet header and its data for accuracy. If the network corrupts or loses a TCP packet during
transmission, TCP is responsible for retransmitting the faulty packet. It can transmit large amounts
of data. Application layer protocols, such as HTTP and FTP, utilize the services of TCP to transfer
files between clients and servers.