Netgear Dgnd4000 N750 Wireless Dual Band Gigabit Adsl2 Plus Modem Router User Manual

							Troubleshooting 
141  N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000
•When entering configuration settings, be sure to click Apply before moving to another 
screen or tab, or your changes could be lost.
•Click Refresh or Reload in the web browser. The changes might have occurred, but the 
web browser might be caching the old configuration.
Changes Not Saved
If the wireless modem router does not save the changes you make in the wireless modem 
router interface, check the following:
•When entering configuration settings, always click the Apply button before moving to 
another screen or tab, or your changes are lost. 
•Click the Refresh or Reload button in the web browser. The changes might have 
occurred, but the old settings might be in the web browser’s cache.
Incorrect Date or Time
Select ADVANCED > Security > Schedule to display the current date and time. The 
wireless modem router uses the Network Time Protocol (NTP) to obtain the current time from 
one of several network time servers on the Internet. Each entry in the log is stamped with the 
date and time of day. Problems with the date and time function can include the following:
•Date shown is January 1, 2000. This value means the wireless modem router has not yet 
successfully reached a network time server. Check that your Internet access is 
configured correctly. If you have finished setting up the wireless modem router, wait at 
least 5 minutes, and check the date and time again.
•Time is off by one hour. The wireless modem router does not automatically sense 
daylight saving time. In the Schedule screen, select the Automatically adjust for daylight 
savings time check box.
Wireless Connectivity
If you are having trouble connecting wirelessly to the wireless modem router, try to isolate the 
problem. 
•Does the wireless device or computer that you are using find your wireless network?
If not, check the Wireless LEDs on the front of the wireless modem router. They should 
be lit. If they are not, you can press the WiFi On/Off button on the front of the wireless 
modem router to turn the wireless modem router’s wireless radio back on.
If you disabled the wireless modem router’s SSID broadcast, then your wireless network 
is hidden and does not show up in your wireless client’s scanning list. By default, SSID 
broadcast is enabled.
•Does your wireless device support the security that you are using for your wireless 
network (WPA or WPA2)? 
						

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142 N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000 
•If you want to view the wireless settings for the wireless modem router, use an Ethernet 
cable to connect a computer to a LAN port on the wireless modem router. Then log in to 
the wireless modem router and select Setup > Wireless Settings see (
Basic Wireless 
Settings on page 34). 
Note:Be sure to click Apply if you made changes.
Wireless Signal Strength
If your wireless device finds your network, but the signal strength is weak, check these 
conditions:
•Is your wireless modem router too far from your computer, or too close? Place your 
computer near the wireless modem router, but at least 6 feet away, and see whether the 
signal strength improves.
•Is your wireless signal blocked by objects between the wireless modem router and your 
computer?
Restore the Factory Settings and Password
This section explains how to restore the factory settings, changing the wireless modem 
router’s administration password back to password. You can erase the current configuration 
and restore factory defaults in two ways:
•Use the Erase function of the wireless modem router (see Erase on page 91).
•Use the Restore Factory Settings button on the back of the wireless modem router. See 
Factory Settings on page 146. If you restore the factory settings and the wireless modem 
router fails to restart, or the green Power LED continues to blink, the unit might be 
defective. If the error persists, you might have a hardware problem and should contact 
technical support at 
http://www.netgear.com/support.
Troubleshoot Your Network Using the Ping Utility
Most network devices and routers contain a ping utility that sends an echo request packet to 
the designated device. The device then responds with an echo reply. You can troubleshoot a 
network by using the ping utility in your computer or workstation. 
Test the LAN Path to Your Router
You can ping the wireless modem router from your computer to verify that the LAN path to 
your wireless modem router is set up correctly. 
						

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143  N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000
To ping the wireless modem router from a computer running Windows:
1. From the Windows toolbar, click Start, and select Run.
2. In the field provided, type ping followed by the IP address of the wireless modem router, as 
in this example:
ping www.routerlogin.net
3. Click OK.
You should see a message like this one:
Pinging  with 32 bytes of data
If the path is working, you see this message:
Reply from < IP address >: bytes=32 time=NN ms TTL=xxx
If the path is not working, you see this message:
Request timed out
If the path is not functioning correctly, you might have one of the following problems:
•Wrong physical connections
For a wired connection, make sure that the numbered LAN port LED is lit for the port to 
which you are connected.
Check that the appropriate LEDs are lit for your network devices. If your wireless modem 
router and computer are connected to a separate Ethernet switch, make sure that the 
Ethernet LEDs are lit for the switch ports that are connected to your computer and 
wireless modem router.
•Wrong network configuration
Verify that the Ethernet card driver software and TCP/IP software are both installed and 
configured on your computer. 
Verify that the IP address for your wireless modem router and your computer are correct 
and that the addresses are on the same subnet.
Test the Path from Your Computer to a Remote Device
After verifying that the LAN path works correctly, test the path from your computer to a 
remote device.
1. From the Windows toolbar, click Start, and select Run.
2. In the Windows Run window, type:
ping -n 10 
where  is the IP address of a remote device such as your ISP’s DNS server.
If the path is functioning correctly, replies like the examples shown in the previous section are 
displayed.
If you do not receive replies: 
						

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144 N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000 
•Check that your computer has the IP address of your wireless modem router listed as the 
default gateway. If the IP configuration of your computer is assigned by DHCP, this 
information is not visible in your computer’s Network Control Panel. Verify that the IP 
address of the wireless modem router is listed as the default gateway.
•Check to see that the network address of your computer (the portion of the IP address 
specified by the subnet mask) is different from the network address of the remote device.
•Check that your cable or DSL modem is connected and functioning.
•If your ISP assigned a host name to your computer, enter that host name as the account 
name in the Internet Basic Settings screen.
•Your ISP might be rejecting the Ethernet MAC addresses of all but one of your 
computers.
Many broadband ISPs restrict access by allowing traffic only from the MAC address of your 
broadband modem, but some ISPs additionally restrict access to the MAC address of a 
single computer connected to that modem. If so, then configure your wireless modem router 
to “clone” or “spoof” the MAC address from the authorized computer.  
						

							145
A
A.   Supplemental Information
Factory settings and technical 
specifications
This appendix provides factory default settings and technical specifications for the N750 
Wireless Dual Band Gigabit ADSL Modem Router DGND4000.
•Factory Settings 
•Technical Specifications  
						

							 Supplemental Information
146 N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000 
Factory Settings
You can return the wireless modem router to its factory settings. Use the end of a paper clip 
or some other similar object to press and hold the Restore Factory Settings button on the 
back of the router for at least 5 seconds. The wireless modem router resets and returns to the 
factory settings.
 Your device returns to the factory configuration settings shown in the 
following table.
Table 13.  Factory default settings  
FeatureDefault Behavior
Router loginUser login URLwww.routerlogin.com or www.routerlogin.net
User name (case-sensitive)admin 
Login password (case-sensitive)password
Internet 
connectionWAN MAC addressUse default hardware address
WAN MTU size1500
Port speedAutosensing
Local network 
(LAN)LAN IP192.168.0.1
Subnet mask255.255.255.0
DHCP serverEnabled
DHCP range192.168.0.2 to 192.168.0.254
Allow a registrar to configure this 
routerEnabled
DHCP starting IP address192.168.0.2
DHCP ending IP address192.168.0.254
Local network 
(LAN) continuedDMZDisabled
Time zoneGMT for WW except NA and GR, GMT+1 for GR, GMT-8 
for NA
Time zone adjusted for daylight 
savings timeDisabled
FirewallInbound (communications coming 
in from the Internet)Disabled (except traffic on port 80, the HTTP port)
Outbound (communications going 
out to the Internet)Enabled (all)
Source MAC filteringDisabled 
						

							 Supplemental Information
147  N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000
WirelessWireless communicationEnabled
SSID nameSee router label
SecurityEnabled
Broadcast SSIDEnabled
Transmission speedAuto1
Country/regionUnited States in the US; otherwise varies by region
RF channel6 until region selected
Operating modeUp to 300 Mbps
Data rateBest
Output powerFull
FirewallInbound (communications coming 
in from the Internet)Disabled (bars all unsolicited requests)
Outbound (communications going 
out to the Internet)Enabled (all)
1. Maximum wireless signal rate derived from IEEE Standard 802.11 specifications. Actual throughput varies. Network conditions 
and environmental factors, including volume of network traffic, building materials and construction, and network overhead, lower 
actual data throughput rate.
Table 13.  Factory default settings  (continued)
FeatureDefault Behavior 
						

							 Supplemental Information
148 N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000 
Technical Specifications
Table 14.  DGND4000 Router specifications  
FeatureDescription
Data and routing protocolsTCP/IP, RIP-1, RIP-2, DHCP, PPPoE, Dynamic DNS, UPnP, and SMB
Power adapter• North America:  120V,  60  Hz,  input
• UK, Australia: 240V, 50 Hz, input
• Europe: 230V, 50 Hz, input
• All regions (output): 12V DC @ 5A, output
Dimensions8.8 in. x 6.8 in. x 1.2 in. (223 x 153 x 31 mm)
Weight1.2 lbs (0.5 kg)
Operating temperature0° to 40°C  (32º to 104ºF)
Operating humidity90% maximum relative humidity, noncondensing
Electromagnetic emissionsFCC Part 15 Class B
VCCI Class B
EN 55 022 (CISPR 22), Class B C-Tick N10947
LAN10BASE-T or 100BASE-Tx, RJ-45
WAN10BASE-T or 100BASE-Tx, RJ-45
WirelessMaximum wireless signal rate complies with the IEEE 802.11 standard. See the 
footnote for the previous table. 
Radio data ratesAuto Rate Sensing
Data encoding standardsIEEE 802.11n version 2.0 
IEEE 802.11n, IEEE 802.11g, IEEE 802.11b 2.4 GHz 
IEEE 802.11n, IEEE 802.11a 5.0 GHz
Maximum computers per 
wireless networkLimited by the amount of wireless network traffic generated by each node 
(typically 50–70 nodes). 
						

							 Supplemental Information
149  N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000
Operating frequency range2.4 GHz
2.412–2.462 GHz (US) 
2.412–2.472 GHz (Japan) 
2.412–2.472 GHz (Europe ETSI)
5 GHz
5.18–5.24 + 5.745–5.825 GHz (US) 
5.18–5.24 GHz (Europe ETSI)
FCC:   
      5.25–5.35 GHz (DFS band) 
      5.47–5.725 GHz (DFS band) 5600–5650 MHz is disabled and  
      unavailable for use
CE (Europe ETSI):   
      5.25–5.35 GHz (DFS band) 
      5.47–5.725 GHz (DFS band) 
802.11 securityWPA-PSK, WPA2-PSK, and WPA/WPA2 Enterprise.
Table 14.  DGND4000 Router specifications  (continued)
FeatureDescription 
						

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Index
A
AC power adapter input 14
access
remote 122
viewing logs 89
access points 105
accessing remote computer 109
adding
custom services 115
guest network 38
priority rules 57
QoS policy 56
wireless devices 26
address reservation 55
ADSL microfilters 18
ADSL port 13
ADSL setup 49
advertisement period 124
alerts, emailing 82
applications, QoS for online gaming 57
approved USB devices 69
attached devices 31
authentication, required by mail server 82
automatic firmware checking 84
automatic Internet connection 44
B
back panel 13
backing up configuration 91
base station, setting up 107
blocking
inbound traffic 109
keywords and sites 76
services 77
box contents 11
C
cables, checking 135
changes not saved, router 141
configuration file 90, 91
connecting wirelessly 17
country setting 43
crossover cable 137
CTS/RTS Threshold 102
custom service (port forwarding) 115
D
dashboard 25
data packets, fragmented 51
date and time 141
daylight savings time 141
default DMZ server 51
default factory settings 12, 91, 146
default gateway 87
denial of service (DoS) protection 75
device mode 127
devices, attached 31
DHCP server 54, 87
DHCP setting 86
DMZ server 51
DNS addresses
primary 30
troubleshooting 139
DNS servers 109
Domain Name Server (DNS) addresses 30, 86
DSL port LED 16
Dynamic DNS 118
E
electromagnetic emissions 148
email notices 82
erasing configuration 91
Ethernet cables, checking 135
Ethernet LED, troubleshooting 136, 137
F
factory default settings
list of 146
resetting 12