A |
---|
access port | | A special interface card in the system cabinet through
which the system console is connected.
|
---|
address | | A numerical identifier defined and used by a particular
protocol and associated software to distinguish one node from another.
|
---|
address key | | See X.25 address
key.
|
---|
address resolution | | In NS networks, the mapping of node names to IP
addresses and the mapping of IP addresses to subnet addresses.
|
---|
address resolution protocol | | ARP. A protocol used by LAN links with Ethernet
enabled that provides a means of exchanging addressing information
between Ethernet nodes.
|
---|
adjacent | | A node on a point-to-point network that is connected
to another node by a single link with no intervening nodes.
|
---|
APRA Telnet Express | | An HP product which is a standalone hardware platform
dedicated to performing protocol translation. Calls to the IP address
of an MPE/iX system are detected by the Telnet Express and are retransmitted
on the LAN using AFCP, allowing connections from terminals on ARPA
systems to HP 3000s.
|
---|
ARPA | | Advanced Research Projects Agency. It is the former
name of the Defense Advanced Research Project Agency (DARPA). The
Internet suite of protocols was developed under ARPA guidance.
|
---|
ARPA Telnet Access | | An HP product which is a board that can be installed
in a DTC 48 and DTC 72MX. The Telnet Access board performs
protocol translation. Calls to the IP address of an MPE/iX system
are detected by the Telnet Access board and are retransmitted on
the LAN using AFCP, allowing connections from terminals on ARPA
systems to HP 3000s.
|
---|
ARPANET | | The (Advanced Research Projects Agency) computer
network.
|
---|
ASCII | | American National Standard Code for Information
Interchange. A character set using 7-bit code used for information
interchange among data processing and data communications systems.
The American implementation of International Alphabet No. 5.
|
---|
asynchronous | | Term used to describe a device's mode of
operation whereby a sequence of operations are executed irrespective
of time coincidence with any event. Devices that are directly accessible
by people (for example, terminal keyboards) operate in this manner.
|
---|
asynchronous processor board | | The new 24-port mux board for the DTC 72MX. Allows
up to 24 direct and modem connections per board. A DTC 72MX
can have up to 3 asynchronous processor boards (for a total of 72
connections).
|
---|
attachment unit interface | | The cable that runs between each node (host, DTC,
or other device) and the Medium Attachment Unit (MAU) that connects
it to the LAN in a ThickLAN configuration.
|
---|
AUI | | See attachment unit
interface.
|
---|
autodial | | A dial link in which the remote node's
telephone number is automatically dialed by a modem or other device
with this capability.
|
---|
automatic configuration | | The addition and configuration of a host-based managed
DTC to the HP 3000 system without needing to specify detailed configuration
information such as DTC cards/boards and ldevs.
|
---|
B |
---|
back-to-back configuration | | A DTC configuration whereby MPE users connected
to one DTC can communicate with a non-MPE/iX system connected to
another DTC via the LAN. (See also Local
Switching)
|
---|
backbone LAN | | A thick LAN cable conforming to the IEEE 802.3
Type 10 BASE 5 standard.
|
---|
backup configuration file | | A file that contains a copy of the information contained
in the configuration file. The backup file, called NMCBACK.group.account
by default, is updated each time the configuration file is successfully
validated.
|
---|
banner | | A welcome message displayed on your screen. On the
local OpenView workstation a banner appears when a remote connection
is established with the OpenView DTC Manager. A banner also can
appear when you log on to MPE.
|
---|
baud | | Measure of the speed at which information travels
between devices, most commonly used in reference to terminal speed
settings. Baud represents signal events per second. When one bit
represents each signal change, baud is the same as "bits
per second".
|
---|
binary mode | | Data transfer scheme in which no special character
processing is performed. All characters are considered to be data
and are passed through with no control actions being taken.
|
---|
bit | | Binary digit. A unit of information that designates
one of two possible states, which are represented by either 1 or
0.
|
---|
block mode | | Terminal processing mode in which groups, or "blocks,"
of data are transmitted all at once.
|
---|
BNC T-Connector | | Connector used to connect a computer or a component
such as a DTC to the LAN in a ThinLAN configuration.
|
---|
boundary | | See network boundary.
|
---|
bps | | Bits per second. The number of bits passing a point
per second.
|
---|
broadcast | | Communication method of sending a message to all
devices on a link simultaneously.
|
---|
byte | | A sequence of eight consecutive bits operated on
as a unit.
|
---|
C |
---|
call | | In X.25, a call is an attempt to set up communication
between two DTEs using a virtual circuit. Also known as a virtual
call.
|
---|
call collision | | A conflict that occurs at a DTE/DCE interface when
there is a simultaneous attempt by the DTE and DCE to set up a call
using the same logical channel identifier.
|
---|
called address | | When a node sends out a call request packet, the
packet contains the address of the destination node. The address
of the destination node is the called address.
|
---|
calling address | | When a node receives an incoming call packet, the
packet contains the address of the sending node. The address of
the sending node is the calling address.
|
---|
carrier | | A continuous wave that is modulated by an information
bearing signal.
|
---|
catenet | | See internetwork.
|
---|
CCITT | | Consultative Committee for International Telephony
and Telegraphy. An international organization of communication carriers,
especially government telephone monopolies, responsible for developing
telecommunication standards by making recommendations. No carrier
is required to adhere to a CCITT recommendation,
although most do so in their own interest.
|
---|
CIB | | The channel input/output bus in the backplane of
an HP 3000.
|
---|
circuit-switching network | | A type of data communications network wherein a
physical and exclusive link is maintained between two communicating
devices for the call duration. An all-digital, circuit-switching
network is often referred to as an X.21 network.
|
---|
closed user group | | An X.25 user facility that allows communication
to and from a pre-specified group of users and no one else.
|
---|
compatibility mode | | Processing mode on HP 3000 Series 900 computers
that allows applications written for MPE V/E-based systems to be
ported and run without changes or recompilation.
|
---|
computer network | | A group of computer systems connected in such a
way that they can exchange information and share resources.
|
---|
configuration | | 1) The way in which computer equipment is physically
interconnected and set up to operate as a system. 2) The layout of the computer system, including the MPE table,
memory, and buffer sizes, that tells which peripheral devices are
(or can be) connected to the computer and how they can be accessed. 3) The process of defining the characteristics of a network
in software. For MPE/iX-based computers, the operating systems are
configured through use of the SYSGEN utility. Next, the datacommunications
and terminal subsystem (DTS) link is configured by using NMMGR (running
on the host) and may, in addition, be configured using the OpenView
DTC Manager software (running on the OpenView Windows Workstation)
depending on the type of network management you use. If any of the
NS link products are installed on the system, network configuration
is accomplished through use of NMMGR and, if PC-based X.25 connections
are required, through the OpenView DTC Manager.
|
---|
configuration file | | he configuration file, which you create and update
using the NMMGR utility, contains: 1) the information that the network needs in order to operate. 2) Information necessary for link-level and NetIPC logging. 3) Information required to connect terminals and printers
to the system through one or more DTC. The only file name that the system recognizes as the configuration
file is NMCONFIG.PUB.SYS.
|
---|
control-X echo | | Three exclamation marks (!!!) output to the terminal
screen when the cancel character (normally [CTRL]-X)
is entered.
|
---|
control-Y trap | | User-written procedure to which control is passed
when the subsystem break character (normally [CTRL]-Y)
is entered during execution of a program with subsystem break enabled.
|
---|
cross-validate | | The process of assuring that information contained
in two locations is consistent where it is imperative that it be
consistent. For example, an automatic cross-validation occurs when
you enter SYSGEN to assure that information contained in NMCONFIG.PUB.SYS
agrees with system configuration data.
|
---|
CSMA/CD | | Carrier Sense Multiple Access with Collision Detect,
transmission access method used by the IEEE 802.3 LAN standard.
|
---|
CSN | | See circuit-switching
network.
|
---|
CTB | | The cache transfer bus in the backplane of an HP
3000.
|
---|
CUG | | See closed user
group.
|
---|
D |
---|
D bit | | Delivery confirmation bit. Used in the X.25 protocol,
the setting of the D bit in DATA packets indicates whether delivery
acknowledgment of the packet is required from the local DCE or from
the remote DTE. It therefore allows the choice between local and
end-to-end acknowledgment.
|
---|
data | | Basic elements of information that can be processed
or produced by a computer.
|
---|
data overrun | | Transmitted data that is sent faster than the equipment
on the receiving end is capable of receiving it. The resulting overflow
data is lost. See also flow control.
|
---|
Datacommunications and Terminal Controller | | See DTC.
|
---|
Datapac | | The national public PSN of Canada.
|
---|
Datex-P | | The national public PSN of West Germany.
|
---|
DCE | | Data circuit-terminating equipment. The interfacing
equipment required in order to interface to data terminal equipment
(DTE) and its transmission circuit. Synonyms: data communications
equipment, dataset.
|
---|
DDX | | The national public PSN of Japan.
|
---|
dedicated printer | | A printer that can be used by only one host on the
LAN; the one specified in the Destination Node Name in that printer's
configuration screen.
|
---|
default gateway | | One (and only one) gateway accessible by a system
may be designated as a default gateway. The network will then send
any transmitted messages for which it is unable to locate a destination
through normal means to the default gateway in a final effort to
determine a transmission route.
|
---|
demodulation | | The process by which the information-bearing signal
is retrieved from a modulated carrier wave. The inverse of modulation.
|
---|
destination node name | | In DTS configuration, it is either 1) the name of
a host that a user can be connected to by default (if switching
is not enabled for that user, or if automatic modem connection is
enabled), or 2) the name of the only host that can access a dedicated
printer.
|
---|
device class | | A collection of devices that have some user-defined
relation. Device classes are assigned through use of the NMMGR configuration
utility.
|
---|
device driver | | Software module that controls a specific type of
input/output device including NS 3000/iX links.
|
---|
device file | | A file being input to or output from any peripheral
device except a disk. MPE allows operations to be performed on the
device itself as if it were a file.
|
---|
device independence | | A characteristic of the operating system that allows
users to selectively redirect input/output from a program, session,
or job without regard to the nature of the device.
|
---|
device name | | See PAD name.
|
---|
device-dependent characteristic | | A file specification for which modifications are
restricted because of the type of device on which the file is opened.
For example, data directed to terminals must have a blocking factor
of one.
|
---|
Dial ID protocol | | A proprietary Hewlett-Packard protocol that provides
security checking and address exchange for dial links.
|
---|
dial link | | A connection made through public telephone lines.
|
---|
direct connection | | A leased line, private line, or other non-switched
link in a network.
|
---|
direct dial | | A dial link through which only one remote node can
be reached.
|
---|
direct-connect device | | Asynchronous device that is connected directly to
a DTC through an RS-232-C or RS-422 cable, with no intervening communications
equipment. Also referred to as a "local connection."
|
---|
direct-path branching | | The process of directly accessing any screen in
NMMGR by entering path names in the Command:
field. The path name must be preceded by an at sign (@).
|
---|
domain name | | A name designated for a system in ARPANET standard
format. This name can be used by other nodes on the network to access
the host for which it is configured.
|
---|
download | | The process of loading operating code and configuration
files into the DTC's memory. The DTC is downloaded by the
host computer for LANs using host-based network management, and
by the PC for DTCs managed by the OpenView DTC Manager.
|
---|
driver | | See device driver.
|
---|
DTC | | Datacommunications and Terminal Controller. The
DTC is a hardware device, configured as a node on a LAN, that enables
asynchronous devices to access HP 3000 Series 900 computers.
Terminals can either be directly connected to the DTC, or they can
be remotely connected through a Packet Assembler Disassembler (PAD).
The DTC can be configured with DTC/X.25 Network Access cards and
DTC/X.25 Network Access software. A DTC/X.25 iX Network Link consists
of two software modules: the X.25 iX System Access software (running
on the host) and the DTC/X.25 Network Access software (running on
the DTC).
|
---|
DTC 16 | | HP 2340A product. A DTC that provides 2 slots for
asynchronous connections with each slot allowing up to 8 direct
connections or 6 modem connections, plus an optional X.25 link supporting
up to 32 virtual circuits at speeds of up to 19.2 Kbps.
|
---|
DTC 16iX | | HP J2062A product. A DTC terminal server for HP 3000
systems. It allows up to 16 asynchronous (direct and modem) LAN
connections to HP 3000 systems.
|
---|
DTC 16MX | | HP J2063A product. A DTC terminal server for HP 3000
and Telnet systems. It allows up to 16 asynchronous (direct and
modem) LAN connections for the HP 3000 environment and for computer
systems running ARPA, such as HP 9000s and third party systems.
When managed by the HP 3000, the DTC 16MX is configured and functions
exactly like a DTC 16iX. The full functionality of the
DTC 16MX is only available when it is managed by the OpenView DTC
Manager.
|
---|
DTC 16RX | | HP J2064A product. A routable communications server
that enables up to 16 asynchronous connections for the HP 3000
environment and computer systems running ARPA, such as HP 9000s
and third party systems.
|
---|
DTC 16RX Manager | | An application program that resides on the HP 9000
host system and enables you to configure and diagnose the HP DTC
16RX Routable Communications Server.
|
---|
DTC 16TN | | HP J2060A product. A DTC terminal server for Telnet
systems. It allows up to 16 asynchronous connections to computer
systems running ARPA, such as HP 9000s and third party systems.
|
---|
DTC 48 | | HP 2345B product. A DTC that provides 6 slots for
asynchronous connections, X.25 links, or Telnet Access. Each slot
allows up to 8 direct connections or 6 modem connections. A DTC 48
may have up to 3 slots used for X.25 links, each supporting up to
256 virtual circuits at speeds of up to 64 Kbps
or one Telnet Access card with 40 Telnet connections to HP 3000
Series 900 connections.
|
---|
DTC 72MX | | HP J2070A product. A DTC that provides 3 slots allowing
up to 72 asynchronous connections. Each slot accommodates up to
24 direct or modem connections. A DTC 72MX may have up
to 3 slots used for X.25 links, each supporting up to 256 virtual
circuits at speeds of up to 64 Kbps. It may also use one slot for
Telnet Access card with 40 Telnet connections to HP 3000 Series
900 computers.
|
---|
DTC identifier | | An identifier used only within NMMGR to define the
branch of the configuration file containing information about a
particular DTC. The identifier must begin with a letter and can
be up to eight characters long.
|
---|
DTC Manager | | See OpenView DTC
Manager.
|
---|
DTC node name | | Unique name used to identify a DTC on the LAN. Node
name format is nodename.domain.organization,
with each of the three parts having up to 16 characters
and beginning with either a letter or a digit.
|
---|
DTC station address (802.3 address) | | 12-digit hexadecimal number used to identify the
DTC as a node belonging to the network configuration. Also called
the LAN address.
|
---|
DTC switching | | A facility enabling terminal users to select any
host system that they want to connect to. DTC switching is available
only when the OpenView DTC Manager is used for network management.
|
---|
DTC/X.25 iX Network Link | | Software and hardware that provides access to private
and public X.25 networks. The X.25 iX System Access software resides
on an HP 3000 host and is configured through use of NMMGR.
|
---|
DTC/X.25 Network Access | | The X.25 software that resides on the Datacommunications
and Terminal Controller (DTC). To configure access to an X.25 network,
you must configure two software components: the X.25 iX System Access
(residing on the HP 3000 host), and the DTC/X.25 Network Access.
DTC/X.25 Network Access is configured through use of the OpenView
DTC Manager software for systems using PC-based network
management or through NMMGR for systems using host-based network
management.
|
---|
DTC/X.25 Network Access card | | This is the hardware card and channel adapter that
provides X.25 Network Access. It resides in the Datacommunications
and Terminal Controller (DTC).
|
---|
DTCCNTRL | | A command file you can use to manage DTS configurations.
Using DTCCNTRL, you can dynamically
implement DTS changes, automatically add a new DTC, shutdown/restart
DTS, and manage/dynamically configure host-based X.25 connections.
|
---|
DTE | | Data Terminal Equipment. Equipment that converts
user information into data-transmission signals or reconverts received
data signals into user information. Data terminal equipment operates
in conjunction with data circuit-terminating equipment.
|
---|
DTS | | Datacommunications and Terminal Subsystem. This
consists of all the Datacommunications and Terminal Controllers
(DTCs) on a LAN, their LANIC cards (attached to the host), the LAN
cable, and the host and DTC software that controls all related DTS
hardware.
|
---|
DTS restart | | The startup of the DTS subsystem, including the
release of all TIO-related resources, using the DTCCNTRL
command file.
|
---|
DTS shutdown | | The shutdown of the DTS subsystem, including the
release of all TIO-related resources, using the DTCCNTRL
command file.
|
---|
duplex | | Transmission method that allows two-way communication.
If both ends of the transmission link can transmit simultaneously,
it is called full duplex. If only one end can transmit at a time,
it is half-duplex transmission.
|
---|
dynamic configuration | | The ability to make DTS configuration changes using
NMMGR without rebooting the HP 3000 system.
|
---|
E |
---|
entry priority | | The ranking that identifies the most desirable route
used to reach a given remote node from a given local node in a point-to-point
network.
|
---|
environment | | A session that is established on a remote node.
|
---|
escape from data transfer character | | A character that allows a user who is connected
to a host system through the DTC to break that connection and return
to the DTC switching user interface. The default is [CTRL]-K.
This character is used only on networks managed by the OpenView
Windows Workstation.
|
---|
escape sequence | | A sequence of characters beginning with the escape
character and followed by one or more other characters, used to
convey control directives to printers, plotters, or terminals.
|
---|
Ethernet | | A Local Area Network system that uses baseband transmission
at 10 Mbps over coaxial cable. Ethernet is a trademark of Xerox
Corporation.
|
---|
event log | | One of three circular files stored on the OpenView
workstation containing lists of all significant events reported
by the DTCs for which it is the owner; that is, whose operating
software/configuration it has downloaded.
|
---|
extended packet sequence numbering | | One of the optional network subscribed facilities
that provides packet sequence numbering using modulo 128. If not
subscribed, modulo 8 is used.
|
---|
F |
---|
facility | | An optional service offered by a packet switching
network's administration and requested by the user either
at the time of subscription for network access or at the time a
call is made. Also known as user facility.
|
---|
facility set | | A facility set defines the various X.25 connection
parameters and X.25 facilities that can be negotiated for each virtual
circuit on a per-call basis.
|
---|
fast select | | An optional packet-switching network facility by
which user data may be transmitted as part of the control packets
that establish and clear a virtual connection.
|
---|
FCS | | Frame Check Sequence. A sequence of bits generated
by X.25 at level 2 that forms part of the frame and guarantees the
integrity of its frame's content. The FCS is also used
by the IEEE 802.3 protocol to check the validity of frames.
|
---|
file equation | | Assignment statement used to associate a file with
a specific device or type of device during execution of a program.
|
---|
file number | | Unique number associated with a file when the file
is opened. The file number is returned in the FOPEN or HPFOPEN call
used to open the file. It can be used to access that file until
the file is closed.
|
---|
file specification | | The name and location of a file. The full specification
for a file includes the file name, group, and account.
|
---|
file system | | The part of the operating system that handles access
to input/output devices (including those connected through the DTC),
data blocking, buffering, data transfers, and deblocking.
|
---|
flow control | | A means of regulating the rate at which data transfer
takes place between devices to protect against data overruns.
|
---|
flow control negotiation | | One of the network subscribed facilities, selected
at subscription time. This facility allows the flow control parameter
to be negotiated at call set-up time, as opposed to having a predefined
value.
|
---|
formal file designator | | Name that can be used programmatically or in a file
equation to refer to a file.
|
---|
FOS | | Fundamental Operating System. The programs, utilities,
and subsystems supplied on the master installation tape that form
the basic core of the operating system.
|
---|
full gateway | | A full gateway is a node that belongs to more than
one network and has one IP address for each network. It uses store
and forward to transfer packets between each network that it belongs
to.
|
---|
G |
---|
gateway | | A node that connects two dissimilar network architectures.
A gateway can be either a single node (full gateway) or two gateway
halves.
|
---|
gateway half | | A node that works in conjunction with another node
on another network to form an internetwork. The only protocol used
by gateway halves is the NS Point-to-Point 3000/iX Link.
See also full gateway.
|
---|
gateway-half link | | A link between the two nodes of a gateway-half pair.
Each of the two nodes of a gateway-half pair has a configured link
(hardware interface card) that is used for the gateway half network
interface. The NS Point-to-Point 3000/iX Link is the only link that
can be used as a gateway-half link.
|
---|
gateway-half pair | | A set of two nodes that are joined by a gateway-half
link. Each node in the pair must have a gateway-half network interface
configured, using the link.
|
---|
guided configuration | | A method of configuring a node in which a subset
of the complete NMMGR interface is presented and defaults of configurable
values are used automatically.
|
---|
H |
---|
handshaking | | A communications protocol between devices or between
a device and the CPU. Provides a method of determining that each
end of a communications link is ready to transmit or receive data
and that transmission has occurred without error.
|
---|
hardware handshake | | Uses modem signals CTS and RTS to pace the data
transfer from the DTC to the attached device. (For DTC 16iX/MX/RX
and DTC 72MX only.)
|
---|
hop count | | See internet hop
count and intranet hop count
|
---|
host computer | | The primary or controlling computer on a network.
The computer on which the network control software resides. For
HP purposes, it may also be used to distinguish the HP 3000
Series 900 system (host) from the DTC.
|
---|
host-based network management | | Method of managing asynchronous communications for
HP 3000 Series 900 computers. All of the control software is configured
on a single host and is downloaded to the DTCs that are managed
by that host. With host-based management, there is a permanent relationship
between each DTC and the host, and terminal users can access only
the single system that owns the DTC their terminal is connected
to.
|
---|
host-based X.25 | | The management of X.25 network connections from
a host computer. Host-based X.25 network connections are made through
a DTC Network Access card installed in a DTC managed by the host.
All configuration is accomplished using the NMMGR utility. It is
not necessary for a PC to be part of the LAN when you are using
host-based X.25.
|
---|
HP ARPA Telnet Express | | A DTC dedicated to providing protocol conversion
between Telnet on TCP/IP and AFCP to allow incoming calls from the
ARPA environment to HP 3000 systems.
|
---|
HP block mode | | Block mode transmission method employed by HP computers
where the system controls the block mode handshake. When HP block
mode is used, the user program need not concern itself with data
transfer protocol.
|
---|
HP PPN | | Hewlett-Packard Private Packet Network. Hewlett-Packard's
own packet-switching X.25 network, which gives users full control
over the administration and security of their data communications.
|
---|
HP TS8 | | A terminal server that can support up to eight asynchronous
serial connections. When used in back-to-back configuration, users
can access HP 3000 MPE/V systems on it via a DTC.
|
---|
I |
---|
idle device timeout | | Timeout defined by the Configure: CPU command. When
the timer lapses, a device connected to the DTC user interface that
is still inactive will be disconnected.
|
---|
IEEE 802.3 | | A standard for a broadcast local area network published
by the Institute for Electrical and Electronics Engineers (IEEE).
This standard is used for both the ThinLAN and ThickLAN implementations
of the LAN.
|
---|
IEEE 802.3 multicast address | | A hexadecimal number that identifies a set of nodes.
This address is used for multicast delivery.
|
---|
IEEE 802.3 nodal address | | A unique hexadecimal number that identifies a node
on an IEEE 802.3 LAN.
|
---|
IEEE 802.5 | | A standard for a token ring network published by
the Institute for Electrical and Electronics Engineers (IEEE). This
standard is used for the Token Ring 3000/iX Network Link.
|
---|
initialization string | | A sequence of control characters used to initialize
a terminal, printer, or plotter when a connection is established
from a host on the network.
|
---|
interactive communications | | Processing that allows users to enter commands and
data at the terminal and receive an immediate response.
|
---|
internet communication | | Communication that occurs between networks.
|
---|
internet hop count | | The number of full gateways plus the number of gateway-half
links that a packet must pass through in moving from source node
to destination.
|
---|
Internet Protocol | | A protocol used to provide routing between different
local networks in an internetwork, as well as among nodes in the
same local network. The Internet Protocol corresponds to layer 3,
the network layer, of the OSI model. See also
IP address.
|
---|
internet routing | | Internet routing involves all the processes required
to route a packet from a node on one network to a destination node
on another network.
|
---|
internetwork | | Two or more networks joined by gateways, bridges,
or routers.
|
---|
intranet communication | | Communication that occurs between nodes in a single
network.
|
---|
intranet hop count | | The number of intermediate nodes that lie between
a source and destination node on the same point-to-point network.
|
---|
intranet routing | | Intranet routing involves all the processes required
to route a packet from one node in a network to another node in
the same network.
|
---|
intrinsic | | System routine accessible by user programs which
provides an interface to operating system resources and functions.
Intrinsics perform common tasks such as file access and device control.
|
---|
IP | | See Internet Protocol.
|
---|
IP address | | Internet Protocol address. An address used by the
Internet Protocol to perform internet routing. A complete IP address
comprises a network portion and a node portion. The network portion
of the IP address identifies a network, and the node portion identifies
a node within the network.
|
---|
IP subnet mask | | See subnet mask.
|
---|
ISO | | International Standards Organization. An international
federation of national standards organizations involved in developing
international standards, including communication standards.
|
---|
L |
---|
LAN | | Local Area Network. A collection of data communication
systems sharing a common cable whereby each system can communicate
directly with another.
|
---|
LAN address | | See station address.
|
---|
LANIC | | See Local Area Network
Interface Controller.
|
---|
LANIC physical path | | The physical location (slot number) of the LANIC
within the SPU.
|
---|
LANIC self-test | | A ROM-based program on a LANIC card that tests and
reports the status of the LANIC hardware.
|
---|
LAP | | Link Access Protocol. The data link protocol specified
by older versions (prior to 1980) of X.25 at level 2 but still permitted
and therefore usable. All new implementations of X.25 must use LAP-B,
and all old implementations must migrate to LAP-B at a future date.
|
---|
LAP-B | | Link Access Protocol - Balanced. The data
link protocol specified by the 1980 version of X.25 at level 2 that
determines the frame exchange procedures. LAP-B must also be used
over direct-connect NS Point-to-Point 3000/iX Links.
|
---|
LCI | | Logical Channel Identifier. Local value on a network
node which identifies the channel used to establish a virtual circuit
(SVC or PVC) through an X.25 network.
|
---|
ldev | | See logical device
number.
|
---|
leased line | | Data-grade telephone line leased directly to a subscriber
and allocated specifically for the subscriber's needs.
|
---|
line speed | | Speed at which data is transferred over a specific
physical link (usually measured in bits or kilobits per second).
|
---|
link name | | The name that represents a hardware interface card.
The link name can contain as many as eight characters. All characters
except the first can be alphanumeric; the first character must be
alphabetic.
|
---|
Local Area Network Interface Controller (LANIC) | | A hardware card that fits into the backplane of
the HP 3000 Series 900 computer and provides a physical
layer interface for local area networks.
|
---|
local connection | | See direct connection.
|
---|
local node | | The computer that you are configuring or that you
are logged on to.
|
---|
local switching | | Feature of the DTC which permits back-to-back configuration
(for connections to an HP 3000 MPE/V host), using two ports of the
same DTC.
|
---|
local user group | | A list defined for a particular DTC and card that
specifies which remote nodes this DTC can send
data to and also which remote nodes this DTC
can receive data from. (See also Closed
User Group).
|
---|
log off | | The termination of a job or session.
|
---|
log on | | The process of initiating a job or session.
|
---|
logging | | The process of recording the usage of network resources.
Events can be logged to both the OpenView workstation and to the
MPE host.
|
---|
logging class | | A number defining the severity of any given event
logged. An operator uses the logging classes to specify which events
are to be logged. Class 1 (catastrophic event) is always logged.
|
---|
logical device number (ldev) | | A value by which the operating system recognizes
a specific device. All DTC devices that are configured as nailed
devices through the NMMGR configuration have ldev numbers permanently
assigned. The DTC devices can then be accessed programmatically
through use of their ldev number. Non-nailed devices have ldev numbers
that are assigned from a pool of available ldev numbers for the
life of their connection to a system. You cannot access non-nailed
devices programmatically.
|
---|
logon device | | See session-accepting
device.
|
---|
loopback | | The routing of messages from a node back to itself.
|
---|
LUG | | See local user group.
|
---|
M |
---|
M bit | | More data bit. Setting this bit in a DATA packet
indicates that at least one more DATA packet is required to complete
a message of contiguous data.
|
---|
maintenance mode | | An NMMGR character mode interface used to manage
both network directory and configuration files. It can be used interactively,
from within the screen mode interface, or as a set of commands entered
via a batch job.
|
---|
map, network | | A drawing that shows the topology of the network.
For networks managed by the OpenView DTC Manager, a network map
must be created through use of the OVDraw capability provided with
the management software. A network map is also a hardcopy drawing
used when planning a network. It shows network topology, node and
network names, addresses, network boundaries (for an internetwork
map), and link types.
|
---|
mapping | | A set of characteristics that describe a route taken
by messages to reach a destination node. This set of characteristics
is configured with NMMGR at every node on a point-to-point network.
One mapping is configured at each node for every other node on the
network to which messages will be sent.
|
---|
MAU | | See medium attachment
unit.
|
---|
medium attachment unit | | A device attached to a ThickLAN coaxial cable that
provides the physical and electrical connection from the AUI cable
to the coaxial cable.
|
---|
MIB | | Management Information Base. A database of information
about a network node used by SNMP.
|
---|
MIT | | Master Installation Tape. Magnetic tape containing
the fundamental operating system for a HP 3000 Series 900 computer.
|
---|
modem | | Modulator/demodulator. A device that modulates and
demodulates signals. Primarily used for modulating digital signals
onto carriers for transmission and for performing the inverse function
at the receiving end. Modems are essential for transmitting and
receiving digital signals over telephone lines.
|
---|
modulation | | Process in which certain characteristics of a carrier
signal are altered in accordance with the changes of an information-bearing
signal.
|
---|
modulo | | Value used as the counting cycle for determining
the send sequence number (N(S)) of frames sent across an X.25 network.
|
---|
MPE/iX | | MultiProgramming Executive/ integrated POSIX. The
operating system of HP 3000 Series 900 computers. The NS 3000/iX
network services operate in conjunction with the MPE/iX operating
system.
|
---|
multiplexer | | A device that allows multiple communication links
to use a single channel.
|
---|
N |
---|
nailed device | | A device with a permanently associated ldev that
was assigned through the NMMGR configuration of the host system
on which the association is established. Nailed devices can be accessed
programmatically through their ldev number. In contrast, non-nailed
devices have ldev numbers that are assigned from a pool of available
ldev numbers for the life of their connection to a system.
|
---|
native mode | | The run-time environment of MPE/iX. In Native Mode,
source code has been compiled into the native instruction set of
the HP 3000 Series 900 computer.
|
---|
neighbor gateway | | A gateway that is in the same network as a given
node.
|
---|
NetIPC | | Network Interprocess Communication. Software that
enables programs to access network transport protocols
|
---|
network | | A group of computers connected so that they can
exchange information and share resources.
|
---|
network address | | This can be either 1) the network portion of an
IP address as opposed to the node portion, or 2) when referring
to X.25 networks, it is a node's X.25 address.
|
---|
network boundary | | The logical division between networks in an internetwork.
|
---|
network directory | | A file containing information required for one node
to communicate with other nodes in 1) an internetwork, 2) an X.25
network, or 3) a network that contains non-HP nodes. The active
network directory on a node must be named NSDIR.NET.SYS.
|
---|
network interface | | NI. The collective software that enables data communication
between a system and a network. A node possesses one or more network
interfaces for each of the networks to which it belongs. Network
interface types are LAN, point-to-point (router), X.25, token ring,
SNA, loopback, and gateway half. The maximum number of supported
NIs is 12, one of which is reserved for loopback.
|
---|
network management | | The collective tasks required to design, install,
configure, maintain, and if necessary, change a network.
|
---|
network map | | A drawing that shows the topology of the network.
For networks managed by the OpenView DTC Manager, a network map
must be created using the OVDraw capability provided with the management
software. A network map is also a hardcopy drawing used when planning
a network. It shows network topology, node and network names, addresses,
network boundaries (for an internetwork map), and link types.
|
---|
Network Services | | NS. Software application products that can be used
to access data, initiate processes, and exchange information among
nodes in the network. The NS 3000/iX Network Services include
RPM, VT, RFA, RDBA, and NFT.
|
---|
network subscribed facilities | | A set of parameters that the user chooses when he
subscribes to the X.25 network; they include flow control negotiation,
use of D-bit, throughput class negotiation and extended packet sequence
numbering.
|
---|
network transport | | Software that corresponds to layers 4 and 3 of the
OSI network architecture model. The function of this software is
to send data out over the appropriate communications link, to receive
incoming data, and to route incoming or outgoing data to the appropriate
destination node.
|
---|
NFT | | Network File Transfer. The network service that
transfers disk files between nodes on a network.
|
---|
NI | | See network interface.
|
---|
NMCBACK.PUB.SYS | | The default file name for the file that contains
a copy of the information contained in the configuration file (NMCONFIG.PUB.SYS).
The backup file is updated each time the configuration file is successfully
validated.
|
---|
NMCONFIG.PUB.SYS | | A file that contains all the network configuration
data for the HP 3000 Series 900 computer on which it resides.
It includes information about the DTCs that can access the system
as well as information about any Network Services (NS) products
running on the system. This is the only file name allowed.
|
---|
NMDUMP | | Node management services trace/log file analyzer.
A utility used to format log and trace files.
|
---|
NMMAINT | | Node management services maintenance utility. A
utility that lists the software module version numbers for all HP AdvanceNet
products, including NS 3000/iX. It detects missing or invalid
software modules.
|
---|
NMMGR | | Node management services configuration manager.
A software subsystem that enables you to configure DTC connectivity
and network access parameters for a HP 3000 Series 900
computer.
|
---|
NMMGRVER | | Node management services conversion utility. A conversion
program that converts configuration files created with NMMGR from
an earlier version to the latest format.
|
---|
NMSAMP1.PUB.SYS | | Sample configuration file supplied with FOS that
can be used as a template for DTS configuration.
|
---|
node | | A computer that is part of a network. The DTC is
also considered to be a node and has its own address.
|
---|
node address | | The node portion of an IP address, which consists
of a node portion and a network portion.
|
---|
Node Management Services Configuration Manager | | See NMMGR.
|
---|
node name | | A character string that uniquely identifies each
system in a network or internetwork. Each node name in a network
or internetwork must be unique; however, a single node can be identified
by more than one node name.
|
---|
node names list | | List defined on the OpenView workstation and subsequently
downloaded to all DTCs for which it is the "owner."
The list specifies all the HP 3000 Series 900 hosts on the LAN that
are accessible from the DTCs.
|
---|
non-adjacent | | Describes a node on an NS Point-to-Point 3000/iX
network that is separated from a given node by intervening or intermediate
node.
|
---|
non-nailed device | | A session accepting device that is not permanently
associated with an ldev number at configuration time. When the user
at such a device logs on to a HP 3000 Series 900, an ldev
is assigned from a pool of ldevs set aside for this purpose at configuration
time. The association between a non-nailed device and this temporarily
assigned ldev exists only for the duration of the session. One advantage
of the use of non-nailed device connections is that configuration
is simplified, since it is not required that each non-nailed device
be individually configured.
|
---|
NS 3000/iX | | A Hewlett-Packard data communication product that
provides minicomputers. NS 3000/iX consists of one or more
links and network services.
|
---|
NS 3000/iX Link | | Software and hardware that provides the connection
between nodes on a network. Some of the NS 3000/iX links
available are the ThinLAN 3000/iX Link and its ThickLAN option,
the DTC/X.25 iX Network Link, the NS Point-to-Point 3000/iX Link,
and the Token Ring 3000/iX Network Link.
|
---|
NS 3000/iX Network Services | | Software applications that can be used to access
data, initiate processes, and exchange information among nodes in
a network. The services are RPM, VT, RFA, RDBA, and NFT.
|
---|
NS Point-to-Point 3000/iX Link | | Hardware and software necessary to create networks
in which data is transmitted from node to node over a defined route
until it reaches its destination. This technique is referred to
as store and forward. Systems in a point-to-point network are connected
by means of leased or dial-up telephone lines. HP 3000 systems attach
to the point-to-point network via HP 3000 Programmable
Serial Interface (PSI) cards that fit into the back of each system's
SPU.
|
---|
NSDIR.NET.SYS | | Name of the active network directory file. See
also network directory.
|
---|
O |
---|
octet | | An eight-bit byte operated upon as an entity.
|
---|
OpenView Admin | | An OpenView Windows program that enables you to
configure how your OpenView Windows applications will function.
For example, it enables you to set a default map for the OpenView
DTC Manager.
|
---|
OpenView Draw | | An OpenView Windows program that enables you to
draw the network map, and to label the components on it.
|
---|
OpenView DTC Manager | | OpenView Windows application that enables you to
configure, control, monitor, and troubleshoot the operation of the
Datacommunications and Terminal Subsystems on the LAN.
|
---|
OpenView Run | | An OpenView Windows program that covers most of
the control features used by the DTC Manager, including monitoring
and diagnostic functions.
|
---|
OpenView Windows | | The set of three programs: OV Admin, OV Draw and
OV Run, running on the OpenView workstation under MS Windows,
that acts as the platform for all OpenView applications, such as
DTC Manager.
|
---|
OpenView Windows Workstation | | The personal computer that provides software downloads
to enable operation of the Datacommunications and Terminal Controller
(DTC). The configuration software that runs on this workstation
is called the OpenView DTC Manager software.
|
---|
OSI model | | Open Systems Interconnection model. A model of network
architecture devised by the International Standards Organization
(ISO). The OSI model defines seven layers of a network architecture,
with each layer performing specified functions.
|
---|
P |
---|
packet | | A block of data whose maximum length is fixed. The
unit of information exchanged by X.25 at level 3. There are DATA
packets and various control packets. A packet type is identified
by the encoding of its header.
|
---|
Packet Exchange Protocol | | PXP. A transport layer protocol used in NS 3000/iX
links to initially establish communication between nodes when NetIPC
socket registry is used.
|
---|
packet-switched network name | | The name of a data communication network adhering
to the CCITT X.25 recommendation. This can be a PDN or a private
network, such as the HP PPN.
|
---|
PAD (Packet Assembler/Disassembler) | | A device that converts asynchronous character streams
into packets that can be transmitted over a packet switching network
(PSN).
|
---|
PAD name | | A name of up to eight characters that is associated
with a configured PAD device. The PAD name is known to both the
DTC and the host systems that the device can access.
|
---|
PAD profile | | Terminal or printer profile that specifies the configuration
characteristics for PAD-connected devices.
|
---|
PAD support | | A software module which can be downloaded to an
X.25 board in a DTC. The software is used to manage connections
with remote PAD devices.
|
---|
partner gateway half | | When gateway halves are used, two gateway halves
are required in order to provide communication between two networks.
Each is the partner of the other.
|
---|
path name | | When configuring with NMMGR, you can type a string
in the COMMAND: field on display
screens to branch to another screen. Each screen has a unique path
name that corresponds to its location in the hierarchy of configuration
screens presented by NMMGR.
|
---|
PDN | | Public Data Network. A data communication network
whose services are available to any user willing to pay for them.
Most PDNs use packet switching techniques.
|
---|
Point-to-Point | | A link that connects either two nodes in an NS Point-to-Point
3000/iX network or two gateway halves.
|
---|
port | | An outlet through which a device can be connected
to a computer, consisting of a physical connection point and controlling
hardware, controlling software, and configurable port characteristics.
Ports can be thought of as data paths through which a device communicates
with the computer.
|
---|
Precision Architecture | | The hardware design structure for the HP 3000 Series
900 computer family.
|
---|
printer name | | Character string of up to 16 characters specified
in the DTC Manager configuration (for networks using OpenView Network
Management) to define a printer by name. Can be shared by several
printers (port pool).
|
---|
printer profile | | A set of configuration characteristics that can
be associated with one or more printers through the NMMGR configuration.
Printer profile specifications include the printer type, line speed,
device class assignment, and other values relevant to printers connected
through a DTC.
|
---|
printer type | | A collection of characteristics that cause a printer
connected to a HP 3000 Series 900 system to act and react in a specified
manner. You can configure a printer to use one of the system-supplied
printer types or you can create custom printer types using workstation
configurator.
|
---|
privileged mode | | A capability assigned to accounts, groups, or users
allowing unrestricted memory access, access to privileged CPU instructions,
and the ability to call privileged procedures.
|
---|
probe protocol | | An HP protocol used by NS 3000/iX IEEE
802.3 networks to obtain information about other nodes on the network.
|
---|
probe proxy server | | A node on an IEEE 802.3 network that possesses
a network directory. A probe proxy server can provide a node with
information about other nodes on the same or other networks of an
internetwork.
|
---|
profile | | A method of grouping device connection specifications
and characteristics so that the set of characteristics can be easily
associated with groups of like devices. See also
printer profile, terminal profile.
|
---|
program captive device | | See programmatic
device.
|
---|
Programmable Serial Interface | | PSI. A hardware card that fits into the backplane
of the HP 3000 Series 900 computer. It provides a physical layer
interface for NS Point-to-Point 3000/iX Links.
|
---|
programmatic device | | A device operating under control of a program running
on a computer. Programmatic devices can be used for input, output,
or both, depending on the device and how it is opened by the controlling
program.
|
---|
protocol | | A set of rules that enables two or more data processing
entities to exchange information. In networks, protocols are the
rules and conventions that govern each layer of network architecture.
They define what functions are to be performed and how messages
are to be exchanged.
|
---|
PSN | | Packet-Switching Network. Any data communication
network using packet- switching techniques wherein data is disassembled
into packets at a source interface and reassembled into a data stream
at a destination interface. A public PSN offers the service to any
paying customer.
|
---|
PSS | | Packet-Switching System. The national public PSN
of the United Kingdom.
|
---|
PVC | | Permanent Virtual Circuit. A permanent logical association
between two physically separate DTEs that does not require call
set-up or clearing procedures.
|
---|
PXP | | See Packet Exchange
Protocol.
|
---|
Q |
---|
Q bit | | Qualified bit. When set in DATA packets the Q bit
signifies that the packet's user data is a control signal for the
remote device, not a message for its user.
|
---|
QuickVal | | A software program that tests whether Network Services
are operating correctly between nodes.
|
---|
R |
---|
RDBS | | Remote Data Base Access. A network service that
allows users to access data bases on remote nodes.
|
---|
reachable network | | A network that can be accessed (with additional
internet hops possibly required) by a particular gateway.
|
---|
remote connect device | | Asynchronous device that is connected to a DTC indirectly,
using a modem and telephone hook-up, or a PAD.
|
---|
remote node | | A node on an internetwork other than the node you
are currently using or referring to.
|
---|
retransmission count (N2) | | The maximum number of times a frame will be retransmitted
following the expiration of the retransmission timer, T1.
|
---|
retransmission timer (T1) | | Length of time the transmitter will wait for an
acknowledgment from the destination address before attempting to
retransmit the frame. When choosing this value, factors like the
line speed and maximum frame size should be taken into account.
|
---|
RFA | | Remote File Access. A network service that allows
users to access files and devices on remote nodes.
|
---|
router network | | See Point-to-Point.
|
---|
routing | | The path that packets, or fragments of a message,
take through a network to reach a destination node.
|
---|
RPM | | Remote Process Management. A network service that
allows a process to programmatically initiate and terminate other
processes throughout a network from any node on the network.
|
---|
RS-232-C | | Electronic Industries Association (EIA) level 1
protocol specification that defines electrical circuit functions
for 25 connector pins. HP provides two implementations of this standard:
a 3-pin version for direct connections up to a distance of 15 meters
(50 feet), and a version which makes use of additional circuits
and can be used for either modem or direct connections.
|
---|
RS-422 | | Electronic Industries Association (EIA) level 1
protocol specification implemented by HP in a 5-pin version which
can be used for direct device connection up to a distance of 1500
meters (4000 feet).
|
---|
S |
---|
security string | | An alphanumeric character string that functions
as a password for dial links. The security string is used by the
dial IP protocol.
|
---|
serial device | | Any device that is attached to and communicates
with a computer by means of a serial transmission interface. Terminals,
printers, and plotters are among the devices that communicate serially
with HP 3000 Series 900 computers.
|
---|
serial transmission | | Method of transferring data in which characters
are transmitted one bit at a time and received one bit at a time
in the order of transmission. This transmission scheme is employed
by devices connected to the system via the DTC.
|
---|
session-accepting device | | A terminal or personal computer running in terminal-emulation
mode that is able to establish an interactive (conversational) session
with an HP 3000 computer. Also referred to as a logon device.
|
---|
shared dial | | A dial link that provides connection to more than
one remote system, although to only one at a time.
|
---|
shared-line access | | Feature that allows two or more HP 3000 Series 900
hosts to use the same DTC/X.25 Network Access card on a DTC to access
an X.25 network.
|
---|
SIC | | Serial Interface Card. Card installed in the front
of the DTC that acts as an interface between a corresponding connector
card (CC) and the DTC's processor.
|
---|
slaved device | | A device that shares the same DTC port as another
device and is connected to the other device, referred to as its
master, by a cable. The actions of the slaved device are controlled
by the master device.
|
---|
SNMP | | Simple Network Management Protocol. An industry
standard for managing networked computers in a multi-vendor environment.
|
---|
SNMP agent | | A network node, such as a DTC, that is able to respond
to SNMP requests.
|
---|
SNP | | Synchronous Network Processor card; an alternative
name for an X.25 board.
|
---|
spooled device | | A printer that is accessed through the spooling
facility. The spooling facility allows a nonsharable device to be
shared among several users by temporarily storing output data on
disk and managing the selection of output spool files destined for
the spooled device.
|
---|
start bit | | Data bit used to signal the start of a character
being transmitted in an asynchronous communication mode.
|
---|
station address | | A 12-digit hexadecimal link-level address used by
the IEEE 802.3 protocol. Every node on an IEEE 802.3 network has
its own station address.
|
---|
stop bit | | Data bit used to signal the end of a character being
transmitted in an asynchronous communication mode.
|
---|
store and forward | | A technique in which messages are passed from one
node to another in a network to reach their destination. Point-to-point
networks use the store and forward technique to transmit messages.
|
---|
subnet | | Another name for a network, especially if the network
is part of an internetwork. The word subnet is also a synonym for
intranet.
|
---|
subnet mask | | Grouping of bits that determines which bits of the
IP address will be used to define a subnetwork. The subnet mask
is configured using the NMMGR utility and specified in the same
format as an IP address.
|
---|
SVC | | Switched Virtual Circuit. Path through an X.25 network
that is established at call set-up time.
|
---|
switching | | See DTC switching.
|
---|
Switching user interface | | User interface available when DTC switching is enabled
that allows terminal users to choose the HP 3000 Series
900 computer with which they want to establish a communication link.
|
---|
synchronous | | A mode of operation or transmission whereby a continuous
data stream is generated without intervals between characters. The
data stream is synchronized by clock signals at the receiver and
transmitter. As a result, fast transmission speeds (above 9600 bps)
are attainable.
|
---|
SYSGEN | | The software program that allows you to configure
the operating system on HP 3000 Series 900 computers.
|
---|
system configuration | | The way you tell the operating system what peripheral
I/O devices are attached and what parameters are required for system
operation.
|
---|
T |
---|
TCP | | See Transmission
Control Protocol.
|
---|
telenet | | A proprietary public data network in the USA.
|
---|
Telnet Access Card (TAC) | | A card that resides in the DTC 48 and provides protocol
conversion between Telnet and AFCP.
|
---|
Telnet Express | | See HP ARPA Telnet
Express.
|
---|
TermDSM | | Terminal online diagnostic support manager. A utility
that provides diagnostic services for DTC connections by means of
a series of commands accessible through the SYSDIAG utility. TermDSM
is used only when DTCs are managed by a host system.
|
---|
terminal name | | Character string of up to 16 characters specified
in the OpenView DTC Manager configuration (for networks using OpenView
Network Management) to define a terminal by name. May be shared
by several terminals (pool port).
|
---|
terminal profile | | A set of configuration characteristics that can
be associated with one or more terminals through the NMMGR configuration.
Terminal profile specifications include the terminal type, line
speed, device class assignment, and other values relevant to terminals
connected through a DTC.
|
---|
terminal type | | A collection of characteristics that cause a terminal
connected to an MPE system to act and react in a specified manner.
You may configure a terminal to use one of the system-supplied terminal
types, or you may create custom terminal types using the workstation
configurator.
|
---|
ThinLAN | | A LAN media that conforms to the IEEE 802.3 Type 10
BASE 2 standard LAN.
|
---|
ThinLAN 3000/iX Link | | Hardware and software necessary to create a broadcast
network, which uses the IEEE 802.3 LAN cable to transmit messages
to all the nodes on the network. The messages are then accepted
only by the node or nodes to which they are addressed. Also includes
the ThickLAN and StarLAN 10 options.
|
---|
throughput class | | A value assigned to a given virtual circuit that
defines how many network resources should be assigned to a given
call. It is determined by the access line speed, packet and window
sizes, and the local network's internal mechanisms.
|
---|
throughput class negotiation | | One of the network subscribed facilities defined
at subscription time. This allows the user to negotiate the throughput
class at call set-up time.
|
---|
timer (T3) | | Length of time that a link can remain in an idle
state. After the expiration of the timer, the link is considered
to be in a non-active, non-operational state and is automatically
reset. The value should be chosen carefully. In particular, it must
be sufficiently greater than the retransmission timer (T1) so that
no doubt exists about the link's state.
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token ring | | A collection of data communication systems sharing
a common cable and communicating by means of the IEEE 802.5 protocol.
In a token ring network, access is controlled by the passing of
a token from node to node. Outgoing messages are attached to the
token and passed with the token until they arrive at the node to
which they are addressed.
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Token Ring 3000/iX Network Link | | Hardware and software required to connect a HP 3000
Series 900 system to a token ring network.
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topology | | The physical arrangement of nodes in a network.
Some common topologies are bus, star, and ring.
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Transmission Control Protocol | | TCP. A network protocol that establishes and maintains
connections between nodes. TCP regulates the flow of data, breaks
messages into smaller fragments if necessary (and reassembles the
fragments at the destination), detects errors, and retransmits messages
if errors have been detected.
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Transpac | | The national public PSN of France.
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transparent mode | | Data transfer scheme in which only a limited number
of special characters retain their meaning and are acted on by the
system. All other characters are considered to be data and are passed
through with no control actions being taken.
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transport, network | | Software that corresponds to layers 3 and 4 of the
OSI network architecture model. The function of this software is
to send data out over the appropriate communications link, to receive
incoming data, and to route incoming or outgoing data to the appropriate
destination node.
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TTUTIL | | Also known as the Workstation Configurator. A program,
TTUTIL.PUB.SYS, on the HP 3000
that is used to create and modify terminal and printer type files.
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Tymnet | | A proprietary public data network in the USA.
|
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typeahead | | A facility that allows terminal users to enter data
before a read is actually posted to the terminal.
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U |
---|
unacknowledged frame number (K) | | The number of frames that can be transmitted without
receiving an acknowledgment from the destination address. When this
number (K) frame is reached, the same K frames are retransmitted.
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unedited mode | | See transparent
mode.
|
---|
uninterruptible power supply | | A hardware device that protects equipment from power
failures and contains an internal storage battery to supply reserve
power.
|
---|
UPS | | See uninterruptible
power supply.
|
---|
V |
---|
V-Series (V.##) CCITT | | A set of CCITT recommendations related to data communication
over a voice-grade telephone network.
|
---|
V.24 | | The CCITT recommendation that defines the function
of the interchange circuits between a DTE and a DCE.
|
---|
validation | | The process of ascertaining whether the network
transport configuration file has been correctly configured. In guided
NMMGR, you do this by pressing the Validate Netxport key.
|
---|
VAN | | Value-Added Network. A data communication network
that uses and pays for facilities belonging to another carrier.
The value-added package is then sold to a user.
|
---|
VC | | See virtual circuit.
|
---|
virtual circuit | | A logical association between two physically separate
DTEs.
|
---|
Virtual Terminal | | A network service that allows a user to establish
interactive sessions on a node.
|
---|
VPLUS | | Software used to generate screens such as those
displayed by NMMGR.
|
---|
VT | | See Virtual Terminal.
|
---|
W |
---|
Workstation Configurator | | A utility (TTUTIL) that allows users to create customized
terminal and printer types by entering data through a series of
VPLUS screens.
|
---|
X |
---|
X.21 | | Defines the physical interface between a DTE and
a DCE of a public data network where the access to the network is
made over synchronous digital lines.
|
---|
X.25 | | Defines the interface between a DTE and a DCE for
packet mode operation on a public data network (PDN).
|
---|
X.25 address | | The X.25 address provided by the network administration
if you are connected to a public data network (PDN).
|
---|
X.25 address key | | An X.25 address key is a label that maps a node's
IP address to its X.25 address and its associated X.25 parameters.
You have a combined maximum of 1024 X.25 address keys in the SVC
and PVC path tables.
|
---|
X.25 iX System Access | | The software that works in conjunction with the
DTC/X.25 Network Access software to provide access to X.25. The
software resides on an HP 3000 host and is configured through
use of NMMGR. To configure access to an X.25 network, you must configure
two software components: the X.25 iX System Access (residing on
the HP 3000 host), and the DTC/X.25 Network Access. DTC/X.25 Network
Access is configured through use of the OpenView DTC Manager software
for systems using PC-based network management or through NMMGR for
systems using host-based network management.
|
---|
X.25 LUG address | | X.25 address of a node belonging to a local user
group (LUG).
|
---|
X.29 | | Defines the interface for data exchange between
a packet-mode DTE and a remote Packet Assembly/Disassembly (PAD)
facility over a packet switching network.
|
---|
X.3 | | Defines the user facilities that should be internationally
available from the packet assembler/disassembler (PAD) facility
when this is offered by a public data network.
|
---|
X.Series (X.##) CCITT recommendations | | A set of recommendations for data communication
networks governing their services, facilities, and the operation
of terminal equipment and interfaces.
|
---|
XON/XOFF protocol | | Flow control used by MPE/iX systems to protect against
data overruns. XON/XOFF protocol is controlled by the data recipient
who sends an XOFF character (ASCII DC3) to the sender if it is unable
to continue to receive data. The sender suspends transmission until
it receives an XON character (ASCII DC1).
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