Cisco PIX 520 - PIX Firewall 520, Онлайн руководство пользователя

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See also Fixup .
Rule—Information added to the configuration to define your security policy in the form of conditional statements
that instruct the PIX Firewall how to react to a particular situation. See also,
address translation and access
control rules.
Serial transmission—Method of data transmission in which the bits of a data character are transmitted
sequentially over a single channel.
SIP—Session Initiation Protocol. Enables call handling sessions, particularly two-party audio conferences, or
"calls." SIP works with Session Description Protocol (SDP) for call signaling. SDP specifies the ports for the
media stream. Using SIP, the PIX Firewall can support any SIP Voice over IP (VoIP) gateways and VoIP proxy
servers. See also
Fixup .
SMTP—Simple Mail Transfer Protocol. Internet protocol providing e-mail services. See also Fixup .
Spoofing—The act of a packet illegally claiming to be from an address from which it was not actually sent.
Spoofing is designed to foil network security mechanisms such as filters and access lists.
SQL*Net—Structured Query Language protocol. An Oracle protocol used to communicate between client and
server processes. See also
Fixup .
SSH—Secure Shell) is an application running on top of a reliable transport layer, such as TCP/IP, that provides
strong authentication and encryption capabilities. Up to five SSH clients are allowed simultaneous access to the
PIX Firewall console. See also
Fixup .
Note: You must generate an RSA key-pair for the PIX Firewall before clients can connect to the PIX Firewall
console. To use SSH, your PIX Firewall must have a Data Encryption Standard (DES) or 3DES (Triple DES)
activation key.
Standby, Standby Unit, Secondary Unit—The backup PIX Firewall unit when two are operating in Failover
mode.
State, Stateful, Stateful Inspection—Network protocols maintain certain data, called state information, at each
end of a network connection between two hosts . State information is necessary to implement the features of a
protocol, such as guaranteed packet delivery, data sequencing, flow control, and transaction or session IDs. Some
of the protocol state information is sent in each packet while each protocol is being used. For example, a web
browser connected to a web server uses
HTTP and supporting TCP/IP protocols. Each protocol layer maintains
state information in the packets it sends and receives. PIX Firewalls inspect the state information in each packet
to verify that it is current and valid for every protocol it contains. This is called stateful inspection and is designed
to create a powerful barrier to certain types of computer security threats.
Static PAT—Static Port Address Translation. A static address maps a local IP address to a global IP address.
Static PAT is a static address that also maps a local port to a global port. See also dynamic
PAT .
Telnet—A terminal emulation protocol for TCP/IP networks such as the Internet. Telnet is a common way to
control web servers remotely.
—Terminal Access Controller Access Control System Plus. Provides remote access authentication
and related services, such as event logging. User passwords are administered in a central database rather than in
individual network devices, providing an easily scalable network security solution. See also
AAA , RADIUS