In computer networking, the Address Resolution Protocol (ARP) is the method for finding a
host's link layer (hardware) address when only its Internet Layer (IP) or some other Network
Layer address is known.
ARP has been implemented in many types of networks; it is not an IP-only or Ethernet-only
protocol. It can be used to resolve many different network layer protocol addresses to interface
hardware addresses, although, due to the overwhelming prevalence of IPv4 and Ethernet, ARP is
primarily used to translate IP addresses to Ethernet MAC addresses.
Telnet (Telecommunication network) is a network protocol used on the Internet or local area
network (LAN) connections.
Typically, telnet provides access to a command-line interface on a remote machine.
The term telnet also refers to software which implements the client part of the protocol. Telnet
clients are available for virtually all platforms
Telnet is a client-server protocol, based on a reliable connection-oriented transport. Typically
this protocol is used to establish a connection to TCP port 23
File Transfer Protocol (FTP):
FTP is a network protocol used to transfer data from one computer to another through a network
such as the Internet. FTP is a file transfer protocol for exchanging and manipulating files over a
TCP computer network. An FTP client may connect to an FTP server to manipulate files on that
server. FTP runs over TCP. It defaults to listen on port 21 for incoming connections from FTP
clients. A connection to this port from the FTP Client forms the control stream on which
commands are passed from the FTP client to the FTP server and on occasion from the FTP
server to the FTP client. FTP uses out-of-band control, which means it uses a separate
connection for control and data. Thus, for the actual file transfer to take place, a different
connection is required which is called the data stream.
In computer networking, the Name/Finger protocol and the Finger user information protocol
are simple network protocols for the exchange of human-oriented status and user information.
Traceroute is a computer network tool used to determine the route taken by packets across an IP
network . An IPv6 variant, traceroute6, is also widely available. Traceroute is often used for
network troubleshooting. By showing a list of routers traversed, it allows the user to identify the
path taken to reach a particular destination on the network. This can help identify routing
problems or firewalls that may be blocking access to a site. Traceroute is also used by
penetration testers to gather information about network infrastructure and IP ranges around a
given host. It can also be used when downloading data, and if there are multiple mirrors available
for the same piece of data, one can trace each mirror to get a good idea of which mirror would be
the fastest to use.