User`s guide

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Simple Mail Transfer Protocol (SMTP)
A TCP/IP protocol used in sending and receiving e-mail. 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. SMTP usually is implemented to operate over Internet port 25. An alternative to SMTP
that is widely used in Europe is X.400. Many mail servers now support Extended Simple Mail
Transfer Protocol (ESMTP), which allows multimedia files to be delivered as e-mail.
Simple Network Management Protocol (SNMP)
A protocol for managing and monitoring network devices. The SNMP architecture enables a
network administrator to manage nodes--servers, workstations, routers, switches, hubs, etc.--on
an IP network; manage network performance, find and solve network problems, and plan for
network growth.
static IP address assignment
The process of assigning a specific IP address to a device. Contrast with assigning a device
through Dynamic Host Configuration Protocol (DHCP), or Automatic Private IP Addressing
(APIPA or Auto-IP).
Telnet
A user command and an underlying TCP/IP protocol for accessing remote computers. On the
web, HTTP and FTP protocols allow you to request specific files from remote computers, but
not to actually be logged on as a user of that computer. With Telnet, you log on as a regular user
with whatever privileges you may have been granted to the specific application and data on that
computer.
Transmission Control Protocol (TCP)
A set of rules used along with the Internet Protocol (IP) to send data in the form of message units
between computers over the Internet. While IP handles the actual delivery of the data, TCP
handles keeping track of the individual units of data (called packets) that a message is divided
into for efficient routing through the Internet. For example, when an HTML file is sent to you
from a web server, the TCP program layer in that server divides the file into one or more packets,
numbers the packets, and then forwards them individually to the IP program layer. Although
each packet has the same destination IP address, it may get routed differently through the
network. At the other end (the client program in your computer), TCP reassembles the individual
packets and waits until they have arrived to forward them to you as a single file. TCP is known
as a connection-oriented protocol, which means that a connection is established and maintained
until such time as the message or messages to be exchanged by the application programs at each
end have been exchanged. TCP is responsible for ensuring that a message is divided into the
packets that IP manages and for reassembling the packets back into the complete message at the
other end. In the Open Systems Interconnection (OSI) communication model, TCP is in layer 4,
the Transport Layer.
Transport Layer Security (TLS)
A protocol that ensures privacy between communicating applications and their users on the
Internet. When a server and client communicate, TLS ensures that no third party may eavesdrop
or tamper with any message. TLS is the successor to the Secure Sockets Layer (SSL).