Workshop

across several disks, and one drive keeps checking information so that if one drive fails, the data
can be rebuilt.
repeater
A device that strengthens a signal so it can travel further distances.
request for comments (RFC)
RFC documents are working notes of the Internet development community. These are often used
to propose new standards. A huge depository of RFC documents can be found at
http://www.internic.net.
Reverse Address Resolution Protocol (RARP)
A protocol that maps Ethernet addresses to IP addresses.
RIP
See Routing Information Protocol.
rlogin
A UNIX program that allows you to connect your terminal to remote hosts. This program is much
like Telnet, except it allows you to dispense with entering your password each time you log in.
Unfortunately, it authenticates you via an IP address, so it’s vulnerable to IP spoofing. See also IP
spoofing.
router
A device that routes packets in and out of a network. Many routers are sophisticated and can serve
as firewalls.
Routing Information Protocol (RIP)
A protocol that allows Internet hosts to exchange routing information. (See RFC 1058 for more
information on RIP.)
RSA
A public key encryption algorithm named after its creators (Rivest, Shamir, and Adleman). RSA
is probably the most popular of such algorithms and has been incorporated into many commercial
applications, including but not limited to Netscape Navigator, Communicator, and even Lotus
Notes. Find out more about RSA at http://www.rsa.com.
S/Key
One-time password system to secure connections. Because each session uses a different password,
sessions that use S/KEY are not vulnerable to packet capture attacks. In other words, even if
someone finds out that the password for your current session is “MYSECRET,” he or she doesn’t
know the password for the next session, “OUTTALUCK.” (Refer to RFC 1760 for more
information.)
Secure Socket Layer (SSL)
A security protocol (created by Netscape Communications Corporation) that allows client/server
applications to communicate free of eavesdropping, tampering, and message forgery. SSL is now
used for secure electronic commerce. To find out more, go to
http://home.netscape.com/eng/ssl3/draft302.txt.
secured electronic transaction (SET)
A standard of secure protocols associated with online commerce and credit card transactions.
(Visa and MasterCard are the chief players in development of the SET protocol.) Its purpose is
ostensibly to make electronic commerce more secure.