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DataBand E V User Manual
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© 2012 Patapsco Designs Ltd
is useful for fault-finding.
Default G ateway
The local IP address of the device which carries packets onto a different network segment. Typically a Router.
De- Multiplexer
A device which takes a single input line and splits tit between many separate devices, allowing one large,
centralised resource to be shared between multiple single users. See also Multiplexer.
Destination
The port or group of ports where a call will exit the Patapsco device. Can also be a Logical Link number for
some products.
DHCP
Dynamic Host Configuration Protocol. Allows a DHCP server (usually a router) to assign IP Address, Subnet
Mask, Default Gateway and DNS settings to an Ethernet device.
DID
Direct Inward Dialing. The same as DDI.
Diff Serv Code
P oint
a field in the header of IP packets for packet classification purposes.
Dual TE I
A method of using a different TEI for each B-channel on an
DSCP
See Diff Serv Code Point
Dynamic Logical
Link
A Logical Link which does not have a configured Destination IP Address. Usage of the Logical Link is defined
by IPMT profiles, and the Patapsco device will pick the Logical Link for use as it is required.
E 1
2048kbps (up to 32 x 64kbps timeslots) HDB3 based protocol. Common in most of the world apart from
North America and Japan.
E arly P ackets
Packets which arrived before the Jitter Buffer had enough free space to collect them.
E gress
The port on which traffic leaves a product – packet traffic exiting the device.
E n- Bloc
When telephony calls are made by dialing all of the numbers at the same time (as opposed to Overlap,
where single digits are dialed one after the other).
E thernet
A networking standard for packet-based traffic.
E TSI
European Telecommunications Standards Institute. A body which standardises telecommunications protocols
in Europe.
F irmware
The operating system of a Patapsco device. All Patapsco devices can hold two separate versions of
Firmware, which can be switched between. Both are Flash Re-writable.
F rames
A single unit of data for transmission. Data is organized into frames which are checked in by the receiving
communication device.
F rames per
P acket
How many frames of TDM or ISDN data a Patapsco device loads into each IP packet. The size of the packets
has an effect on the required bandwidth in the system and the quality of the clock recovery.
F ull- Duplex
When a connection is able to transmit and receive at the same time. Essential for Patapsco IP-based
products.
G ateway
A device which changes the media of communications and carries data onto another type of network. See
also Default Gateway.
G roup
Ports on a Patapsco device can be bound together in a Group for routing purposes.
Half- Duplex
When a connection is not able to transmit and receive at the same time. Patapsco IP-based products cannot
function with this type of connection. A Full-Duplex connection must be made.
Hop
A hop is the term for when a packet is routed through a gateway or router. The number of Hops in a system
can impact the performance of an application, and packets can be configured with a TTL value, which
prevents the packet from being re-routed