Netgear C3700 N600 Wifi Cable Modem Router User Manual

							Share a USB Drive Attached to the Modem Router 41
 N600 WiFi Cable Modem Router Model C3700
4. 
Select  ADVANCED > Advanced Setup > USB Settings.
By default Enable any USB Device connection to the USB port radio is sel\
ected. This 
setting lets you connect and access all your USB drives.
5.  Select the No radio button.
6.  Click the  Approved Devices button. 
The approved and available USB devices display. 
7.  In the Available USB Devices list, select the drive that you want to approve.
8.  Click the  Add button.
9.  Select the  Allow only approved devices  check box.
10.  Click the  Apply button.
Your change takes effect.
11.  T
o work with another USB device, first click the  Safely Remove USB Device button for the 
currently connected USB device. Connect the other USB device, and repeat\
 this process. 
						

							Share a USB Drive Attached to the Modem Router 
42 N600 WiFi Cable Modem Router Model C3700 
Safely Remove a USB Drive
Before you physically disconnect a USB drive from the modem router USB port, log in to the 
modem router and take the drive offline.
To remove a USB disk drive safely: 
1. Launch a web browser from a computer or wireless device that is connected to the 
network.
2. Type http://routerlogin.net or http://192.168.0.1.
A login screen displays.
3. Enter the modem router user name and password.
The user name is admin. The default password is password. The user name and 
password are case-sensitive.
The BASIC Home screen displays.
4. Select USB Storage > Basic Settings.
5. Click the Safely Remove USB Device button. 
This takes the drive offline.
6. Physically disconnect the USB drive. 
						

							43
6
6.   Specify Network Settings
This chapter includes the following sections:
•View or Change the WAN Settings 
•Change the MTU Size 
•Set Up a Default DMZ Server 
•Change the Modem Router’s Device Name 
•Change the LAN TCP/IP Settings 
•Specify the IP Addresses That the Modem Router Assigns 
•Reserve LAN IP Addresses 
•Use the WPS Wizard for WiFi Connections 
•Specify Basic WiFi Settings 
•Change the WiFi Security Option 
•Set Up a WiFi Guest Network 
•Control the Wireless Radios 
•Specify WPS Settings 
•Set Up a Wireless Card Access List 
•Dynamic DNS 
•Improve Network Connections with Universal Plug and Play  
						

							Specify Network Settings 44
N600 WiFi Cable Modem Router Model C3700 
View or Change the WAN Settings
You can view the wide area network (WAN) settings for the Internet port. You can set up a 
DMZ (demilitarized zone) server, change the maximum transmit unit (MTU) size, and enable 
the modem router to respond to a ping to its WAN (Internet) port. 
To view or change the WAN settings:
1.  Launch a web browser from a computer or wireless device that is connecte\
d to the 
network.
2.  T
ype  http://routerlogin.net  or http://192.168.0.1.
A login screen displays.
3.  Enter the modem router user name and password.
The user name is  admin. 
 The default password is password . The user name and 
password are case-sensitive.
The BASIC Home screen displays.
4.  Select 
ADVANCED > Setup > WAN Setup.
5.  V
iew or change the following settings:
•Disable IPv4 Firewall Protection. 
 The IPv4 firewall is enabled by default, which is 
the recommended setting. Some advanced users might want to disable IPv4 \
firewall 
protection to examine the traffic coming in from the Internet.
• Disable Port Scan and DoS Protection. DoS protection protects your LAN against 
denial of service attacks such as Syn flood, Smurf 

Attack, Ping of Death, and many 
others. Select this check box only in special circumstances. 
• Default DMZ Server . 
 This feature is sometimes helpful when you are playing online 
games or videoconferencing, but it makes the firewall security less effective. See  Set 
Up a Default DMZ Server on page  47.
• Respond to Ping on Internet Port. 
 This feature allows your modem router to be 
discovered. Use this feature only as a diagnostic tool or if you have a \
specific reason.  
						

							Specify Network Settings 
45  N600 WiFi Cable Modem Router Model C3700
•Disable IGMP Proxying. IGMP proxying allows a computer on the local area network 
(LAN) to receive the multicast traffic it is interested in from the Internet. If you do not 
need this feature, you can select this check box to disable it.
•MTU Size (in bytes). The normal MTU (maximum transmit unit) value for most 
Ethernet networks is 1500 bytes, or 1492 bytes for PPPoE connections. Change the 
MTU only if you are sure that it is necessary for your ISP connection. See 
Change the 
MTU Size on page 45.
•Disable SIP ALG. Some VoIP applications do not work well with the SIP ALG. 
Selecting this check box to turn off the SIP ALG might help your VoIP devices to 
create or accept a call through the modem router.
6. Click the Apply button.
Your changes are saved.
Change the MTU Size
The maximum transmission unit (MTU) is the largest data packet a network device transmits. 
When one network device communicates across the Internet with another, the data packets 
travel through many devices along the way. If a device in the data path has a lower MTU 
setting than the other devices, the data packets must be split or “fragmented” to 
accommodate the device with the smallest MTU. 
The best MTU setting for NETGEAR equipment is often the default value. In some situations, 
changing the value fixes one problem but causes another. Leave the MTU unchanged unless 
one of these situations occurs:
•You experience problems connecting to your ISP or other Internet service, and the 
technical support of either the ISP or NETGEAR recommends changing the MTU setting. 
These web-based applications might require an MTU change:
-A secure website that does not open, or displays only part of a web page
-Yahoo email
-MSN portal
-America Online’s DSL service
•You use VPN and have severe performance problems.
•You used a program to optimize MTU for performance reasons, and now you have 
connectivity or performance problems.
Note:An incorrect MTU setting can cause Internet communication 
problems. For example, you might not be able to access certain 
websites, frames within websites, secure login pages, or FTP or 
POP servers. 
						

							Specify Network Settings 46
N600 WiFi Cable Modem Router Model C3700 
To change the MTU size:
1.
Launch a web browser from a computer or wireless device that is connecte\
d to the 
network.
2. T
ype  http://routerlogin.net  or http://192.168.0.1.
A login screen displays.
3. Enter the modem router user name and password.
The user name is  admin. 
 The default password is password . The user name and 
password are case-sensitive.
The BASIC Home screen displays.
4. Select  ADV
 ANCED > Setup > WAN Setup . 
5.In the MTU Size field, enter a value from 64 to 1500.
6. Click the  Apply button.
Your change is saved.
If you suspect an MTU problem, a common solution is to change the MTU to\
 1400. If you are 
willing to experiment, you can gradually reduce the MTU from the maximum\
 value of 1500 
until the problem goes away

. The following table describes common MTU sizes and 
applications.  
Table 2.  Common MTU sizes   
MTUApplication
1500 The largest Ethernet packet size. This setting is typical for connections that do not use 
PPPoE or VPN, and is the default value for NETGEAR modem routers, adapte\
rs, and 
switches.
1492 Used in PPPoE environments.
1472 Maximum size to use for pinging. (Larger packets are fragmented.)
1468 Used in some DHCP environments.
1460 Usable by AOL if you do not have large email attachments, for example.
1436 Used in PPTP environments or with VPN. 
						

							Specify Network Settings 
47  N600 WiFi Cable Modem Router Model C3700
Set Up a Default DMZ Server
The default DMZ server feature is helpful when you are using some online games and 
videoconferencing applications that are incompatible with Network Address Translation 
(NAT). The modem router is programmed to recognize some of these applications and to 
work correctly with them, but other applications might not function well. In some cases, one 
local computer can run the application correctly if the IP address for that computer is entered 
as the default DMZ server.
WARNING:
DMZ servers pose a security risk. A computer designated as the 
default DMZ server loses much of the protection of the firewall and 
is exposed to exploits from the Internet. If compromised, the DMZ 
server computer can be used to attack other computers on your 
network.
The modem router usually detects and discards incoming traffic from the Internet that is not a 
response to one of your local computers or a service that you have configured in the Port 
Forwarding/Port Triggering screen. Instead of discarding this traffic, you can have the modem 
router forward the traffic to one computer on your network. This computer is called the default 
DMZ server.
To set up a default DMZ server: 
1. Launch a web browser from a computer or wireless device that is connected to the 
network.
2. Type http://routerlogin.net or http://192.168.0.1.
A login screen displays.
3. Enter the modem router user name and password.
The user name is admin. The default password is password. The user name and 
password are case-sensitive.
The BASIC Home screen displays.
4. Select ADVANCED > Setup > WAN Setup.
5. Select the Default DMZ Server check box.
6. Type the IP address.
1400Maximum size for AOL DSL.
576Typical value to connect to dial-up ISPs.
Table 2.  Common MTU sizes  (continued)
MTUApplication 
						

							Specify Network Settings 48
N600 WiFi Cable Modem Router Model C3700 
7. 
Click the  Apply button.
Your change takes effect.
Change the Modem Router’s Device Name
The modem router’s  device name is C3700. This device name displays in file manager when 
you browse your network.
To change the modem router’s device name:
1.  Launch a web browser from a computer or wireless device that is connecte\
d to the 
network.
2.  T
ype  http://routerlogin.net  or http://192.168.0.1.
A login screen displays.
3.  Enter the modem router user name and password.
The user name is  admin. 
 The default password is password . The user name and 
password are case-sensitive.
The BASIC Home screen displays.
4.  Select  ADV
 ANCED > Setup > LAN Setup .
5. In the Device Name field, type a new name.
6.  Click the  Apply button.
Your change is saved. 
						

							Specify Network Settings 49
 N600 WiFi Cable Modem Router Model C3700
Change the LAN TCP/IP Settings
The modem router is preconfigured to use private IP addresses on the LAN\
 side and to act 
as a DHCP server. The modem router’s default LAN IP configuration is as follows:
• LAN IP address . 192.168.0.1
• Subnet mask. 255.255.255.0
These addresses are part of the designated private address range for use\
 in private networks  and are suitable for most applications. If your network requires a dif
 ferent IP addressing 
scheme, you can change these settings
You might want to change these settings if you need a specific IP subnet \
that one or more  devices on the network uses, or if you have competing subnets with the s\
ame IP scheme.
To change the LAN TCP/IP settings:
1.  Launch a web browser from a computer or wireless device that is connecte\
d to the 
network.
2.  T
ype  http://routerlogin.net  or http://192.168.0.1.
A login screen displays.
3.  Enter the modem router user name and password.
The user name is  admin. 
 The default password is password. The user name and 
password are case-sensitive.
The BASIC Home screen displays.
4.  Select  ADV
 ANCED > Setup > LAN Setup .
5. In the IP Address field, type the IP address.
6.  In the IP Subnet Mask  field type the subnet mask of the modem router.  
						

							Specify Network Settings 
50 N600 WiFi Cable Modem Router Model C3700 
The IP address and subnet mask identify which addresses are local to a specific device 
and which must be reached through a gateway or modem router.
7. Click the Apply button.
Your changes are saved.
If you changed the LAN IP address of the modem router, you are disconnected when this 
change takes effect.
To reconnect, close your browser, relaunch it, and log in to the modem router.
Specify the IP Addresses That the Modem Router Assigns
By default, the modem router acts as a Dynamic Host Configuration Protocol (DHCP) server. 
The modem router assigns IP, DNS server, and default gateway addresses to all computers 
connected to the LAN. The assigned default gateway address is the LAN address of the 
modem router. 
These addresses must be part of the same IP address subnet as the modem router’s LAN IP 
address. Using the default addressing scheme, define a range between 192.168.0.2 and 
192.168.0.254, although you can save part of the range for devices with fixed addresses.
To specify the pool of IP addresses that the modem router assigns:
1. Launch a web browser from a computer or wireless device that is connected to the 
network.
2. Type http://routerlogin.net or http://192.168.0.1.
A login screen displays.
3. Enter the modem router user name and password.
The user name is admin. The default password is password. The user name and 
password are case-sensitive.
The BASIC Home screen displays.