Hughes DW4020 manual

IP address - a 32-bit number that identifies each sender or receiver of information that is sent in packets across the Internet. An IP address has two parts: the identifier of a particular network on the Internet and an identifier of the particular device (which can be a server or a workstation) within that network. On the Internet itself - that is, between the router that move packets from one point to another along the route - only the network part of the address is looked at.

L

Local area network (LAN) - a group of computers and associated devices that share a common communications line and typically share the resources of a single processor or server.

N

National Operations Center - A place from which a network is supervised, monitored, and maintained.

Network Address Translation - a method of connecting multiple computers to the Internet (or any other IP network) using one IP address.

P

Performance enhancing proxy (PEP) - modules that provide TCP acceleration. PEP is used to improve the performance of the Internet protocols on network paths where native performance suffers due to characteristics of a link or subnetwork on the path.

Private IP addressing - A computer on the Internet is identified by its IP address. In order to avoid address conflicts, IP addresses are publicly registered with the Network Information Centre (NIC). Computers on private TCP/IP LANs however do not need public addresses, since they do not need to be accessed by the public. For this reason, the NIC has reserved certain addresses that will never be registered publicly. These are known as private IP addresses.

R

Receive modem - downloads data from the satellite. Also known as indoor receive unit (IRU).

Router - a device or, in some cases, software in a computer, that determines the next network point to which a packet should be forwarded toward its destination.

S

Signal quality factor (SQF) - an integer value from 0-99 that indicates the strength of the received satellite signal relative to noise.

Subnet mask - a 32-bit value that is used to distinguish the network ID from the host ID in an arbitrary IP address. Each host on a network requires a subnet mask.

T

TCP/IP internet protocol suite - the basic communication language or protocol of the Internet.

TCP spoofing - technique of using local devices to answer TCP overhead messages. Also known as Turbo Internet.

Transmission control protocol (TCP) - a set of rules (protocol) used along with the Internet Protocol (IP) to send data in the form of message units between computers over the Internet. While IP takes care of handling the actual delivery of the data, TCP takes care of keeping track of the individual units of data (called packets) that a message is divided into for efficient routing through the Internet.

Transmit modem - sends (uploads) data to the satellite. Also known as indoor transmit unit (ITU).

64	• Glossary
	1031484-0001 Revision 2