Network Terminology
* 10BASE-T

An Ethernet networkstandard. The number "10" in its name indicates an Ethernet transmission rate of 10Mbps, and the suffix "T" indicates that a twisted pair cable is used as the transmission medium. It employs "Category 3" (voice grade) UTP cable consisting of two twisted pair cables, with one pair being used for signal transmission and the other for signal reception. The maximum transmission distance is generally 100m, and up to three repeater hubs can be connected in series.
* 100BASE-TX

Also called the "First Ethernet," 100BASE-TX is an Ethernet network standard. The number "100" in its name indicates an Ethernet transmission rate of 100Mbps, and the letter "T" in the suffix indicates that a twisted pair cable is used as the transmission medium. The "X" indicates that 100BASE-TX is based on FDDI specifications originally established in compliance with optical fiber specifications. It employs "Category 5" (data grade) UTP cable consisting of two twisted pair cables, with one pair being used for signal transmission and the other for signal reception. The transmission rate is 100Mbps, and the maximum transmission distance is 100m. Up to 2 repeater hubs can be connected in series.
* ADSL (Asymmetric Digital Subscriber Line)

One of the most representative versions of xDSL high-speed digital transmission technology that utilizes general telephone lines. Downstream signal transmission speeds from the telephone company central office to subscriber premises differ from upstream speeds from the subscriber premises to the central office, hence the term "asymmetric." The maximum transmission rate is 6 - 12MB/sec. downstream and 640 k - 1MB/sec. upstream. ADSL is evolving as a technology that enables relatively inexpensive around-the-clock high-speed connections to the Internet.
* ARP (Address Resolution Protocol)

The protocol contained within the TCP/IP suite that is used to obtain the MAC address from the IP address.
Networking equipment maintain the physical IP and MAC addresses obtained by ARP for a specific period of time as an ARP table, and reuse the information.
* Broadcast

Broadcast is the simultaneous transmission of data to an infinite number of receiving devices over a network. Broadcast transmissions are carried out by designating a special address that represents the entire network. Conversely, sending data to a specific receiving device by designating a single address is referred to as "unicast," while simultaneously sending data to multiple designated devices is referred to as "multicast."
* Browser

The software used to access Web server and, among other functions, view Web pages on the Internet. Browsers transfer HTTP protocol files, and decode and display hypertext described in the HTML language. Representative browsers include Netscape Navigator and Microsoft Internet Explorer, among others.
* CGI (Common Gateway Interface)

A standard feature of many Web server software programs, this function interfaces between the Web server and applications. The CGI permits operation of other applications in the Web server, or creation and return to the browser of the files that dynamically make up pages based on results derived from those applications.
* Class (IP Address)

IP addresses, which identify each connected piece of equipment on a network, are divided into 5 classes: A - E.
Classes A to C are normally used. Class D is used in multicast transmissions, and Class E is a reserved address not currently in use.
Class
Usable Address Range
Maximum No. of Networks
Maximum No. of Hosts
A
0.0.0.0 - 127.255.255.255
128
16,777,216
B
128.0.0.0 - 191.255.255.255
16,384
65,536
C
192.0.0.0 - 223.255.255.255
2,097,152
256
D
224.0.0.0 - 239.255.255.250
Multicast addresses
E
240.0.0.0 - 247.255.255.255
Reserved addresses
* Default Gateway

The default gateway refers to such devices as routers that represent a "gateway" used when accessing external equipment from within a network. If no specific gateway is designated as the IP address of the destination to be accessed, data is transmitted to the device designated as the default gateway.
A default gateway must be set when connecting this equipment to a device outside its subnet.
* Ethernet

Ethernet is a communications standard established by the IEEE 802.3 Committee. Most of today's LAN employ Ethernet, except in specialized applications. Ethernet reflects Layer 1 (physical layer) and Layer 2 (data link layer) of the OSI model. Everything from the range of cables and connectors used to electrical content is defined in the physical layer, while the methods of transmitting and receiving data between physically connected equipment are defined in the data link layer. Formerly, bus type LAN using coaxial cables such as 10Base-2 and 10Base-5 were the most widely used, and later star-type 10Base-T and 100Base-TX (Fast Ethernet) using UTP cable grew to become the standard. Recent trends now point toward even higher speed communications, as evidenced by the growth of 1000Base-T (Gigabit Ethernet) LANs.
* Full-Duplex and Half-Duplex Communication

Full-duplex communication refers to a communication format in which data is simultaneously transmitted and received between two devices. Full-duplex communication permits data to be transmitted at any time without worry of data collision.
Conversely, while half-duplex communication permits data transmission and reception, it cannot perform these functions simultaneously. In half-duplex communication, a device is required to prevent data collision by only permitting data transmission after ensuring that no signal is being transmitted from the other party.
* Global IP Address

The IP address authorized for use on the Internet, which is managed by the international institution called the Network Information Center (NIC). This global IP address is assigned to the Internet as the only address, and is required for connection to the Internet. The global IP address contrasts with the private IP address.
* HTTP(HyperText Transfer Protocol)

The protocol used to transmit and receive data between a Web server and a browser (Web client). HTTP handles the HTML files and images, voices, or animations associated with such files.
This equipment has a built-in Web server, with HTTP being used by the setup software program or browser to perform settings.
* HTML(HyperText Markup Language)

This is the programming language used to create data that can be processed over an IP network. By embedding a command-called a "tag"-into ordinary text documents, the image to be displayed on the browser can be designated, or the size and layout of displayed characters can be set as desired. Most Internet home pages are described using this HTML language.
This equipment contains HTML files, which can be viewed by a browser.
* HUB (Repeater Hub)

A networking device that operates at the network Layer 1 (physical layer) of the OSI model, the repeater hub is a line concentrator for electrically branching or interconnecting the network. Since it uses half-duplex communications unlike a switch (switching hub) and data is broadcast-transmitted to all ports, when any one of the ports is in use, equipment connected to the remaining ports cannot be used for communications.
Since this equipment uses full-duplex communications, switches (switching hubs) should be used instead of repeater hubs.
* Internet

A network that links multiple networks to each other. Today, computers throughout the world have become linked to the Internet by interconnecting the networks of individual groups (schools, corporations, research institutes, etc.). The TCP/IP protocol, which is not dependant on specialized equipment, is used on the Internet, permitting communications to be efficiently carried out between different types computers.
This equipment also uses the TCP/IP protocol, and can thus be connected to the Internet.
* IP (Internet Protocol)

IP is the common communication protocol used by communications equipment on a LAN or the Internet. It operates at the network layer (layer 3) of the OSI model, and routes outgoing messages as packets to be delivered to their designated final destination.
* IP Address and IP Network

Networks using the Internet Protocol (IP) are called IP networks, and the identification numbers assigned to each connected piece of equipment in the IP network are called IP addresses. IP addresses are divided into two types: the global IP address used for Internet connections, and private IP addresses that can be freely used on a local area network.
This equipment utilizes an IP network to communicate audio and control information.
* IP Masquerade

Also called NAPT (Network Address and Port Translation), IP Masquerade is a technology used to convert the global IP address and private IP addresses, with port numbers as well as the IP network included. Unlike NAT, two or more private IP addresses can be assigned to a single global IP address.
* ISDN (Integrated Services Digital Network)

ISDN is a digital communication network that comprehensively handles telephone, fax, and data communications. ISDN standardization was begun by CCITT (currently ITU-T) in the 1970s, and Japan's NTT began the world's first service under the name of "INS Net" in April, 1988. It still offers an ISDN service called "FLETS ISDN" even today.
In ISDN, the basic data transmission speed is 64kbps (for INS64 service).
* ISP (Internet Service Provider)

Generally called a "provider," an ISP is a vendor who provides customer access to the Internet.
To connect this equipment to the Internet using eitherASDL or ISDN, a contract for obtaining fixed assigned global IP addresses must be concluded with an ISP.
* JavaScript

A scripting language (programming language that does not need to be compiled) designed to be executed by a browser. JavaScript performs computations, checks values input in forms, or dynamically displays characters on Web pages. Since This equipment is designed to use JavaScript through browser settings, use a browser that can handle JavaScript, and set Java functions to ON when operating this equipment.
* LAN (Local Area Network)

A short-distance data communications network typically used within corporate buildings or on campuses to link computers and printers, etc. IP networks constructed using private IP addresses are called LANs.
* Loop-Back Address

The IP address "127.0.0.1" is referred to as the Loop-back address, and is a virtual IP address that permits transmitted packets to be returned to the sender.
(Generally, not only "127.0.0.1" but also "127.*.*.*" is reserved as a Loop-back address.)
* MAC (Media Access Control) Address

The address used to identify an Ethernet device.
For this equipment, the MAC address can be verified by means of the Setup software program contained in its supplied CD or labels attached to the unit's front panel. Because the MAC address is the unit's own address, knowing the location and MAC address facilitates name or IP address settings.
* Modem

A device that converts digital signals to analog and analog signals to digital in order to enable communications between two computers over telephone lines.
* Multicast

The simultaneous broadcast of identical data to multiple designated stations on a network. This function is frequently used to distribute images over an IP network. Unlike unicast, multicast transmission does not produce multiple packets with the same contents, thus helping to reduce the amount of network congestion. The Class D IP address is used to use this function.
Multicast is best used to simultaneously broadcast to multiple equipments and send messages to more units with less congestion over the network.
* NAT (Network Address Translator)

NAT is a technology used to link the global IP address and the private IP address in an IP network. Since the global IP address and the private IP address are converted in a matching ratio of 1:1, IP Masquerade should be used when simultaneously linking two or more private IP addresses.
* Network Address

The address used to identify a network. The network address is an address in which the segment called the "host address" of the IP address is all zeros (0).
For more information, refer to Subnet Mask.
* Packet

A generic term for a bundle of data. Data transfer by packet is performed in Ethernet communications, with the destination address and control information other than data being added to the packet.
* Ping

A command used to check that devices are communicating in the IP network.
If an acknowledgement is received after executing a "ping," the device can be assumed to be performing correct communications.
* Port Number

Port numbers are used by the TCP or UDP protocols. These protocols use port numbers because they assign packets depending on each application. Part of the port number is an officially assigned number called a "Well-known port number," of which No. 80 represents HTTP.
* Private IP Address

This is an IP address that can be freely used in each organization of an IP network. It does not, however, provide access to the Internet for communications. Equipment assigned only a private address can only access the Internet through a relay device that has been assigned a global IP address by way of the NAT, IP Masquerade or proxy server.
[Private Address Range]
Class
Usable Address Range
No. of Connectable Devices
A
10.0.0.1 - 10.255.255.254
16,777,214
B
172.16.0.1 - 172.31.255.254
1,048,574
C
192.168.0.1 - 192.168.255.254
65,534
* Proxy Server

A proxy server is a computer that connects to the Internet and caches WWW data, etc. in place of other computers on a network that cannot be directly connected to the Internet. By reducing the access number of external equipment, access to specific pages can be restricted.
* Router

Equipment that "sees" the destination unit address being transmitted over the network, and finds the most efficient path to it. Routers operate at Layer 3 (network layer) of the OSI model.
When performing network settings for equipment on a network, connections can be made to such external networks as the Internet by way of the designated router by designating the routerfs IP address as a default gateway.
* RTP (Real-time Transport Protocol)

RTP is a transmission protocol used to stream (simultaneously reproduce while receiving a signal) voices or images. This is a UDP-type protocol that does not provide measures for packet loss or assurance of transmission time, and is usually used in conjunction with a communication status report protocol called RTCP. Today, QuickTime and RealPlayer are compatible with the RTP.
* Streaming

Streaming is a data transmission system which permits simultaneous recording of images, audio or other multimedia data as it is being received through an IP network, such as the Internet.
This equipment uses streaming for transmitting voice signals.
* Subnet Mask

The TCP/IP network is managed by being divided into multiple small subnetworks (subnets). The subnet mask refers to a 32-digit number which determines the number of bits used as a network address to identify a subnetwork from the IP addresses. When the binary subnet mask is 11111111 11111111 11111111 00000000 (255.255.255.0 in the decimal system), the higher-order 24 bits of the IP address are called the network address, while the lower-order 8 bits are referred to as the host address. Dividing the IP address 192.168.10.32 by the subnet mask 255.255.240.9 (11111111 11111111 11110000 00000000 in binary form) translates to the network address 192.168.0 and the host address 10.32.
* Switching Hub

A networking device that operates at the network Layer 2 (data link layer) of the OSI model. Switches check the destination address (MAC address) of packets received from a connected node against an internal address table, and transmit the packets to only the port a destination terminal is connected to. Because of this, unlike repeater hubs, which broadcast received packets to all other ports, switching hubs allow other idle ports to be freely used even though communications are in progress between a certain pair of ports. Moreover, full-duplex communications can be carried out.Because this equipment performs full-duplex communication, switches (switching hubs) should be used instead of repeater hubs.
* TA (Terminal Adapter)

An adapter necessary for connecting communications devices (such as computers, modems, analog telephones and fax machines) that cannot be directly connected to ISDN lines to ISDN lines.
* TCP/IP (Transmission Control Protocol/Internet Protocol)

A protocol used as a standard in Internet or Intranet communications. The IP operates at the network layer (layer 3) of the SDI model, while the TCP operates at the transport layer (layer 4), creating a protocol that provides a base for HTTP and FTP transmissions.
* UDP (User Datagram Protocol)

This protocol contrasts with TCP.
Because TCP begins to communicate after a connection (session) has been established, it is able to carry out reliable communications. However, whenever an error occurs, TCP continues to retransmit data until correct reception has been confirmed, resulting in slower overall data transmission, which makes it unsuitable for audio streams that require real-time operation.
UDP, on the other hand, continues transmission without regard to data errors or losses. Because no data transmission delays occur, UDP is better suited to real-time data transmissions.
This equipment is configured to use UDP to transmit audio streams.
* Unicast

The broadcast of data to a specific station by designating a single address in the network.
* UTP (Unshielded Twisted-Pair)

Twisted pair cables with no shields designed for use in 10BASE-T or 100BASE-TX networks. UTP cables are classified by "Category" depending on their transmission quality. Category 5 UTP cable is recommended for use with this equipment.
* WAN (Wide Area Network)

This type of network covers a greatly expanded geographical area and uses telephone lines to link computers (for example, in a corporate headquarters) to other computers in remote buildings (such as branch offices) in distant cities.
* Web, WWW (World Wide Web)

A standardized Internet or Intranet document system. Document formats are written in the HTML language, and images, audio or other data besides characters, as well as the position of other documents (hyperlinks) can be embedded in the document. This application is most frequently used in the Internet.