Triz TZ6100i, Руководство пользователя

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Dial Up
The process of initiating a switched connection through the network; when used as an
adjective, this is a type of communication that is established by a switched-circuit
connection.
Digital Loop Carrier
Equipment used to concentrate many local loop pairs onto a few high-speed digital
pairs or one fiber optic pair for transport back to the CO.
DHCP
Dynamic Host Configuration Protocol – This protocol allows computers on a network to
dynamically obtain an IP address and network configuration from a server or a router.
The DSL PCI modem supports this option under the "Networking Configuration" utility.
DMT (Discrete Multitone)
A modulation scheme in which available bandwidth is divided into many sub-channels.
Each sub-channel is then analyzed for its ability to carry digital data. Noisy sub-
channels carry few or zero bits, while clear channels carry a maximum number of bits.
Thus, DMT essentially assures the telephone companies and consumers that they are
achieving the greatest throughput possible over any given copper line. In March 1993,
ANSI selected DMT technology as the standard line code for DSL. ETSI then
contributed an annex to T1.413 to reflect European requirements.
DNS
Domain Name Service is provided by a server. It matches the domain name of a
machine to its IP address. Internet applications can find servers on the Internet by their
name or IP address. If the ISP offers this service, it will specify the IP address of the
DNS server. The DSL PCI modem allows the user to configure this on the "Network
Properties" screens found on the "DSL Configure" tool.
Downstream
Downstream refers to data flowing from the source, such as a corporate host or ISP to
the end user.
DS0 (Digital Signal 0)
64 kbps digital representation of voice.
DS1 (Digital Signal 1)
Twenty four voice channels packed into a 193 bit frame and transmitted at 1.544 Mbps.
The unframed version, or payload, is 192 bits at a rate of 1.536 Mbps.
DS2 (Digital Signal 2)
Four T1 frames packed into a higher level frame transmitted at 6.312 Mbps.
DSL (Digital Subscriber Line)
Modems on either end of a single twisted pair wire that delivers ISDN Basic Rate
Access.