Workshop

providers.
Point-to-Point Tunneling Protocol (PPTP)
A Microsoft-developed specialized form of PPP. PPTP’s unique design makes it possible to
encapsulate or “wrap” non-TCP/IP protocols within PPP. Through this method, PPTP allows two
or more LANs to connect using the Internet as a conduit.
Post Office Protocol (POP3)
A protocol that allows workstations to download and upload Internet electronic mail from
centralized servers. (See RFC 937 for more information.)
PPP Authentication Protocols
A set of protocols that can be used to enhance the security of the Point-to-Point Protocol. (Refer to
RFC 1334.)
PPP DES
The PPP DES Encryption Protocol, which applies the data encryption standard protection to pointto-point
links. This is one method to harden PPP traffic against sniffing. (To learn more, refer to
RFC 1969.)
PPP
See Point-to-Point Protocol.
PPTP
See Point-to-Point Tunneling Protocol.
presentation layer
Layer 6 of the OSI reference model. This layer manages the protocols of the operating system,
formatting data for display, encryption, and translation of characters.
protocol
A standardized set of rules that govern communication or the way that data is transmitted.
protocol analyzer
See network analyzer.
protocol stack
A hierarchy of protocols used in data transport, usually arranged in a collection called a suite
(such as the TCP/IP suite). The actual programs used to implement a protocol stack are
colloquially called a “stack” as well (for example, the Microsoft TCP/IP stack.)
proxy server
A server that makes application requests on the behalf of a client and relays results back to the
client. Often used for a simple firewall; routing domains are typically different. See also
application gateway.
pulse code modulation (PCM)
A system of transforming signals from analog to digital. (Many high-speed Internet connections
from the telephone company use PCM.)
RARP
See Reverse Address Resolution Protocol.
read access
When a user has read access, he or she has privileges to read a particular file.
redundant array of inexpensive disks (RAID)
A large number of hard drives connected together that act as one drive. The data is spread out