Coyote Point Systems E350GX, Installation And Administration Manual

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Appendix J: Glossary
326 Equalizer Installation and Administration Guide
NAT subsystem The Equalizer subsystem responsible for transferring connections to and from
the back-end servers.
netmask Address mask; a bit mask used to select bits from an Internet address for
subnet addressing. The mask is 32 bits long and selects the network portion
of the Internet address and one or more bits of the local portion.
Network Address Translation
(NAT) See NAT.
network interface The place at which two or more networks connect and communicate with
each other. See interface. See external interface, interface, and internal
interface.
network route See gateway.
OSI network A network that uses the International Organization for Standardization/Open
Systems Interconnection model. See ISO/OSI model, Layer 4, Layer 7, and
transport layer.
packet A group of data that is transmitted as a single entity.
passive FTP connection An Equalizer option that rewrites outgoing FTP PASV control messages from
the servers so that they contain the IP address of the virtual cluster rather
than that of the server. See FTP and PASV.
PASV Passive mode FTP; a mode with which you can establish FTP connections for
clients that are behind firewalls. See firewall, FTP, and passive FTP
connections.
pattern match A pattern of ASCII or hexadecimal data that filters data.
payload The set of data to be transmitted. A payload contains user information, user
overhead information, and other information that a user requests. A payload
does not include system overhead information. Also known as the mission bit
stream.
persistence The act of storing or retaining data for use at a later time, especially data that
shows the state of the network before processing resumes. See cookie and
IP-address-based persistence.
physical server A machine located on the internal network that provides services on specific
IP addresses and ports. See server and virtual web server. See also
authoritative name server, back-end server, name server, and proxy server.
piece An atom followed by a single *, +, or ?, or by a bound. See atom, branch, and
regular expression.
ping A program used to test reachability of destinations by sending them an ICMP
echo request and waiting for a reply. See echo and probe. See also CMP
echo request
port The abstraction used by Internet transport protocols to distinguish among
multiple simultaneous connections to a single destination host.
port number The number used to identify a service contact port, such as HTTP port 80.
primary Equalizer The primary unit that handles requests. If the primary Equalizer fails, the
backup unit replaces it. See also backup Equalizer and hot backup.
probe An action that obtains status information about a computer, network, or
device. See geographic probe and ping.
protocol A set of rules that govern adherence to a set of standards. See protocol stack.