Hughes DIRECWAY DW4020 User Manual

The DW4020 provides connectivity from a satellite network to 
multiple computers.

From the point of view of the individual computer user, the 
DW4020 provides the link to the outside world. DW4020s direct 
data traffic by inspecting the IP addresses. A DW4020 is assigned 
two IP addresses, one in each network that it links.

Figure 52 illustrates a typical connection scheme for the 
DW4020.

The subnet mask defines the part of the IP address used to 
identify computers on the same LAN from computers in other 
departments or elsewhere in the world. Computers on the same 
LAN can send messages directly to each other. Messages for 
other LANs and the rest of the world need to be sent through a 
router. In a scheme where the first three bytes identify the LAN 
network, the subnet mask is 255.255.255.0. The decimal number 
255 corresponds to the binary number 11111111. In IP address 
notation, 0 is interpreted to mean “this.”

Figure 52: Typical DW4020 connection scheme

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IP Address

170.15.100.2

170.15.100.3

170.15.100.4              170.15.100.5

LAN IP Address: 170.15.100.1

LAN

IP Address

170.15.99.1

Gateway

IP Address

170.15.xxx.yyy

HNS Network Operations Center

(NOC)

Hub

GWH

ITU

IRU

USB

25 Pin

Connector

From LAN

DW4020