TCP : RFC 793 TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language or protocol of the Internet. It can also be used as a communications protocol in a private network (either an intranet or an extranet). When you are set up with direct access to the Internet, your computer is provided with a copy of the TCP/IP program just as every other computer that you may send messages to or get information from also has a copy of TCP/IP. UDP: RFC 768 UDP (User Datagram Protocol) is an alternative communications protocol to Transmission Control Protocol (TCP) used primarily for establishing low-latency and loss tolerating connections between applications on the Internet. Both UDP and TCP run on top of the Internet Protocol (IP) and are sometimes referred to as UDP/IP or TCP/IP. Both protocols send short packets of data, called datagrams. UDP provides two services not provided by the IP layer. It provides port numbers to help distinguish different user requests and, optionally, a checksum capability to verify that the data arrived intact. IPv4: RFC 791 Internet Protocol being a layer-3 protocol (OSI) takes data Segments from layer-4 (Transport) and divides it into packets. IP packet encapsulates data unit received from above layer and add to its own header information. IPv4 is a connectionless protocol for use on packet-switched networks. It operates on a best effort delivery model, in that it does not guarantee delivery, nor does it assure proper sequencing or avoidance of duplicate delivery. These aspects, including data integrity, are addressed by an upper layer transport protocol, such as the Transmission Control Protocol (TCP). IPv6 : RFC 2460 IPv6 (Internet Protocol version 6) is a set of specifications from the Internet Engineering Task Force (IETF) that\'s essentially an upgrade of IP version 4 (IPv4). The basics of IPv6 are similar to those of IPv4 -- devices can use IPv6 as source and destination addresses to pass packets over a network, and tools like ping work for network testing as they do in IPv4, with some slight variations. The most obvious improvement in IPv6 over IPv4 is that IP addresses are lengthened from 32 bits to 128 bits. This extension anticipates considerable future growth of the Internet and provides relief for what was perceived as an impending shortage of network addresses. IPv6 also supports auto-configuration to help correct most of the shortcomings in version 4, and it has integrated security and mobility features. HTTP : RFC 1945 HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web. As soon as a Web user opens their Web browser, the user is indirectly making use of HTTP. HTTP is an application protocol that runs on top of the TCP/IP suite of protocols (the foundation protocols for the Internet). HTTP concepts include (as the Hypertext part of the name implies) the idea that .

1. TCP : RFC 793
TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language
or protocol of the Internet. It can also be used as a communications protocol in a private network
(either an intranet or an extranet). When you are set up with direct access to the Internet, your
computer is provided with a copy of the TCP/IP program just as every other computer that you
may send messages to or get information from also has a copy of TCP/IP.
UDP: RFC 768
UDP (User Datagram Protocol) is an alternative communications protocol to Transmission
Control Protocol (TCP) used primarily for establishing low-latency and loss tolerating
connections between applications on the Internet. Both UDP and TCP run on top of the Internet
Protocol (IP) and are sometimes referred to as UDP/IP or TCP/IP. Both protocols send short
packets of data, called datagrams.
UDP provides two services not provided by the IP layer. It provides port numbers to help
distinguish different user requests and, optionally, a checksum capability to verify that the data
arrived intact.
IPv4: RFC 791
Internet Protocol being a layer-3 protocol (OSI) takes data Segments from layer-4 (Transport)
and divides it into packets. IP packet encapsulates data unit received from above layer and add to
its own header information.
IPv4 is a connectionless protocol for use on packet-switched networks. It operates on a best
effort delivery model, in that it does not guarantee delivery, nor does it assure proper sequencing
or avoidance of duplicate delivery. These aspects, including data integrity, are addressed by an
upper layer transport protocol, such as the Transmission Control Protocol (TCP).
IPv6 : RFC 2460
IPv6 (Internet Protocol version 6) is a set of specifications from the Internet Engineering Task
Force (IETF) that's essentially an upgrade of IP version 4 (IPv4). The basics of IPv6 are similar
to those of IPv4 -- devices can use IPv6 as source and destination addresses to pass packets over
a network, and tools like ping work for network testing as they do in IPv4, with some slight
variations.
The most obvious improvement in IPv6 over IPv4 is that IP addresses are lengthened from 32
bits to 128 bits. This extension anticipates considerable future growth of the Internet and
provides relief for what was perceived as an impending shortage of network addresses. IPv6 also
supports auto-configuration to help correct most of the shortcomings in version 4, and it has
integrated security and mobility features.
HTTP : RFC 1945

2. HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files (text, graphic
images, sound, video, and other multimedia files) on the World Wide Web. As soon as a Web
user opens their Web browser, the user is indirectly making use of HTTP. HTTP is an
application protocol that runs on top of the TCP/IP suite of protocols (the foundation protocols
for the Internet).
HTTP concepts include (as the Hypertext part of the name implies) the idea that files can
contain references to other files whose selection will elicit additional transfer requests.
SMTP: RFC 5321
SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-
mail. However, since it is limited in its ability to queue messages at the receiving end, it is
usually used with one of two other protocols, POP3 or IMAP, that let the user save messages in a
server mailbox and download them periodically from the server. In other words, users typically
use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving e-mail.
On Unix-based systems, sendmail is the most widely-used SMTP server for e-mail. A
commercial package, Sendmail, includes a POP3 server. Microsoft Exchange includes an SMTP
server and can also be set up to include POP3 support.
Solution
TCP : RFC 793
TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language
or protocol of the Internet. It can also be used as a communications protocol in a private network
(either an intranet or an extranet). When you are set up with direct access to the Internet, your
computer is provided with a copy of the TCP/IP program just as every other computer that you
may send messages to or get information from also has a copy of TCP/IP.
UDP: RFC 768
UDP (User Datagram Protocol) is an alternative communications protocol to Transmission
Control Protocol (TCP) used primarily for establishing low-latency and loss tolerating
connections between applications on the Internet. Both UDP and TCP run on top of the Internet
Protocol (IP) and are sometimes referred to as UDP/IP or TCP/IP. Both protocols send short
packets of data, called datagrams.
UDP provides two services not provided by the IP layer. It provides port numbers to help
distinguish different user requests and, optionally, a checksum capability to verify that the data
arrived intact.
IPv4: RFC 791
Internet Protocol being a layer-3 protocol (OSI) takes data Segments from layer-4 (Transport)

3. and divides it into packets. IP packet encapsulates data unit received from above layer and add to
its own header information.
IPv4 is a connectionless protocol for use on packet-switched networks. It operates on a best
effort delivery model, in that it does not guarantee delivery, nor does it assure proper sequencing
or avoidance of duplicate delivery. These aspects, including data integrity, are addressed by an
upper layer transport protocol, such as the Transmission Control Protocol (TCP).
IPv6 : RFC 2460
IPv6 (Internet Protocol version 6) is a set of specifications from the Internet Engineering Task
Force (IETF) that's essentially an upgrade of IP version 4 (IPv4). The basics of IPv6 are similar
to those of IPv4 -- devices can use IPv6 as source and destination addresses to pass packets over
a network, and tools like ping work for network testing as they do in IPv4, with some slight
variations.
The most obvious improvement in IPv6 over IPv4 is that IP addresses are lengthened from 32
bits to 128 bits. This extension anticipates considerable future growth of the Internet and
provides relief for what was perceived as an impending shortage of network addresses. IPv6 also
supports auto-configuration to help correct most of the shortcomings in version 4, and it has
integrated security and mobility features.
HTTP : RFC 1945
HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files (text, graphic
images, sound, video, and other multimedia files) on the World Wide Web. As soon as a Web
user opens their Web browser, the user is indirectly making use of HTTP. HTTP is an
application protocol that runs on top of the TCP/IP suite of protocols (the foundation protocols
for the Internet).
HTTP concepts include (as the Hypertext part of the name implies) the idea that files can
contain references to other files whose selection will elicit additional transfer requests.
SMTP: RFC 5321
SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-
mail. However, since it is limited in its ability to queue messages at the receiving end, it is
usually used with one of two other protocols, POP3 or IMAP, that let the user save messages in a
server mailbox and download them periodically from the server. In other words, users typically
use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving e-mail.
On Unix-based systems, sendmail is the most widely-used SMTP server for e-mail. A
commercial package, Sendmail, includes a POP3 server. Microsoft Exchange includes an SMTP
server and can also be set up to include POP3 support.