Cisco PIX 520 - PIX Firewall 520, Онлайн руководство пользователя

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the outside interface. See PAT .
Internet—The global network which uses IP, Internet protocols. Not a LAN . See also intranet .
Intranet—Intranetwork. A LAN which uses IP, Internet protocols. See also network , Internet .
IP—Internet Protocol. The Internet protocols are the world's most popular open-system (nonproprietary) protocol
suite because they can be used to communicate across any set of interconnected networks and are equally well
suited for LAN and WAN communications.
IP Address—IP version 4 addresses are 32-bits, or 4 bytes, in length. This address "space" is used to designate
the following:
network number
●
optional subnetwork number
●
a host number
●
The 32 bits are grouped into four octets (8 binary bits), represented by 4 decimal numbers separated by periods or
"dots". The meaning of each of the four octets is determined by their use in a particular
network .
LAN—Local Area Network. A network residing in one location or belonging to one organization, typically, but
not necessarily using the
Internet protocols . Not the global Internet . See also intranet , network , Internet .
M-P
Mask, IP Subnet Mask, Netmask, —A 32-bit bit mask which shows how an Internet address is to be divided
into network, subnet and host parts. The netmask has ones in the bit positions in the 32-bit address which are to
be used for the network and subnet parts, and zeros for the host part. The mask should contain at least the
standard network portion (as determined by the address's class), and the subnet field should be contiguous with
the network portion. See also
IP Address , TCP/IP , host , host/network.
NAT—Network Address Translation. Mechanism for reducing the need for globally unique IP addresses . NAT
allows an organization with addresses that are not globally unique to connect to the Internet by translating those
addresses into globally routable address space. There are two types of NAT—
static and dynamic . See also, PAT ,
Static PAT .
Netmask—See Mask .
Network—In the context of PIX Firewall configuration, a network is a group of computing devices which share
part of an
IP address space and not a single host . A network consists of multiple "nodes" or devices with IP
address, any of which may be referred to as "hosts". See also Internet , Intranet , IP , LAN .
Node—See host , network
Nonvolatile storage, memory—Storage or memory which, unlike RAM (Random Access Memory) retains its
contents without power. Data in a nonvolatile storage device survives a power-off, power-on cycle or reboot.
Outbound—Outbound CLI commands lets you specify whether inside users can create outbound connections.