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purposes.
PPTP:
Point-to-Point Tunneling Protocol (PPTP) is
a protocol (set of communication rules) that allows
corporations to extend their own corporate network
through private "tunnels" over the public Internet.
Effectively, a corporation uses a wide-area network
as a single large local area network. This kind of
interconnection is known as a virtual private
network (VPN).
R
RADIUS:
RADIUS (Remote Authentication Dial-In
User Service) is a client/server protocol and
software that enables remote access servers to
communicate with a central server to authenticate
dial-in users and authorize their access to the
requested system or service. RADIUS allows a
company to maintain user profiles in a central
database that all remote servers can share. It
provides better security, allowing a company to set
up a policy that can be applied at a single
administered network point. Having a central
service also means that it's easier to track usage for
billing and for keeping network statistics.
S
SNMP:
Simple Network Management Protocol
(SNMP) is the protocol governing network
management and the monitoring of network devices
and their functions. It is not necessarily limited to
TCP/IP networks.
SNMP is described formally in the Internet
Engineering Task Force (IETF) Request for
Comment (RFC) 1157 and in a number of other
related RFCs.
SSL:
The Secure Sockets Layer (SSL) is a
commonly-used protocol for managing the security
of a message transmission on the Internet. SSL has
recently been succeeded by Transport Layer
Security (TLS), which is based on SSL. SSL uses a
program layer located between the Internet's
Hypertext Transfer Protocol (HTTP) and Transport
Control Protocol (TCP) layers. The "sockets" part of
the term refers to the sockets method of passing
data back and forth between a client and a server
program in a network or between program layers in
the same computer. SSL uses the
public-and-private key encryption system from RSA,
which also includes the use of a digital certificate.
T
TCP:
TCP (Transmission Control Protocol) is a set
of rules (protocol) used along with the Internet
Protocol (IP) to send data in the form of message
units between computers over the Internet. While IP
takes care of handling the actual delivery of the data,
TCP takes care of keeping track of the individual
units of data (called packets) that a message is
divided into for efficient routing through the Internet.
TCP is 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.
TCP/IP:
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.
TCP/IP is a two-layer program. The higher layer,
Transmission Control Protocol, manages the
assembling of a message or file into smaller
packets that are transmitted over the Internet and
received by a TCP layer that reassembles the
packets into the original message. The lower layer,
Internet Protocol, handles the address part of each
packet so that it gets to the right destination.
TKIP:
The Temporal Key Integrity Protocol (TKIP),
pronounced “tee-kip”, is part of the IEEE 802.11i
encryption standard for wireless LANs. TKIP is
the next generation of WEP, the Wired
Equivalency Protocol, which is used to secure
802.11 wireless LANs. TKIP provides per-packet
key mixing, a message integrity check and a
re-keying mechanism, thus fixing the flaws of
WEP.
Telnet:
Telnet is the way to access someone else's
computer, assuming they have given permission.
(Such a computer is frequently called a host
computer.) More technically, Telnet is a user
command and an underlying TCP/IP protocol for
accessing remote computers. On the Web, HTTP
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