D-Link DGS-1008D Unmanaged Gigabit Ethernet Switch
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Glossary
1000BASE-LX
a short laser wavelength on multimode fiber optic cable for a maximum length of 550
meters
1000BASE-SX
a long wavelength for a "long haul" fiber optic cable for a maximum length of 10
kilometers
100BASE-FX
100Mbps Ethernet implementation over fiber.
100BASE-TX
100Mbps Ethernet implementation over Category 5 and Type 1 Twisted Pair cabling.
10BASE-T
The IEEE 802.3 specification for Ethernet over Unshielded Twisted Pair (UTP) cabling.
ageing
The automatic removal of dynamic entries from the Switch Database which have timed-out and are
no longer valid.
ATM
Asynchronous Transfer Mode. A connection oriented transmission protocol based on fixed length
cells (packets). ATM is designed to carry a complete range of user traffic, including voice, data and video
signals.
auto-negotiation
A feature on a port which allows it to advertise its capabilities for speed, duplex and flow
control. When connected to an end station that also supports auto-negotiation, the link can self-detect its
optimum operating setup.
backbone port
A port which does not learn device addresses, and which receives all frames with an
unknown address. Backbone ports are normally used to connect the Switch to the backbone of your network.
Note that backbone ports were formerly known as designated downlink ports.
backbone
The part of a network used as the primary path for transporting traffic between network segments.
bandwidth
Information capacity, measured in bits per second, that a channel can transmit. The bandwidth
of Ethernet is 10Mbps, the bandwidth of Fast Ethernet is 100Mbps.
baud rate
The switching speed of a line. Also known as
line speed
.
between network segments.
BOOTP
The BOOTP protocol allows you to automatically map an IP address to a given MAC address each
time a device is started. In addition, the protocol can assign the subnet mask and default gateway to a device.
bridge
A device that interconnects local or remote networks no matter what higher level protocols are
involved. Bridges form a single logical network, centralizing network administration.
broadcast
A message sent to all destination devices on the network.
broadcast storm
Multiple simultaneous broadcasts that typically absorb available network bandwidth and
can cause network failure.
console port
The port on the Switch accepting a terminal or modem connector. It changes the parallel
arrangement of data within computers to the serial form used on data transmission links. This port is most
often used for dedicated local management.
CSMA/CD
Channel access method used by Ethernet and IEEE 802.3 standards in which devices transmit
only after finding the data channel clear for some period of time. When two devices transmit simultaneously,
a collision occurs and the colliding devices delay their retransmissions for a random amount of time.
data center switching
The point of aggregation within a corporate network where a switch provides high-
performance access to server farms, a high-speed backbone connection and a control point for network
management and security.
Ethernet
A LAN specification developed jointly by Xerox, Intel and Digital Equipment Corporation.
Ethernet networks operate at 10Mbps using CSMA/CD to run over cabling.
Fast Ethernet
100Mbps technology based on the Ethernet/CD network access method.
Flow Control
(IEEE 802.3z) A means of holding packets back at the transmit port of the connected end
station. Prevents packet loss at a congested switch port.
forwarding
The process of sending a packet toward its destination by an internetworking device.
full duplex
A system that allows packets to be transmitted and received at the same time and, in effect,
doubles the potential throughput of a link.
half duplex
A system that allows packets to be transmitted and received, but not at the same time. Contrast
with
full duplex
.
