Netgear R6250 Smart Wifi Router Ac1600 User Manual

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The Block Services screen lets you add and block specific Internet servi\
ces by computers on 
your network. This is called service blocking or port filtering. To add a service for blocking, 
first determine which port number or range of numbers the application us\
es. 
To block services:
1. 
Select 
Advanced > Security > Block Services .
2. Select either Per Schedule or  Always.
3.  If you selected Per Schedule, specify a time period in the Schedule scre\
en.
4.  Click  Add to add a service. 
The Block Services Setup screen displays:
5.  From the Service Type list, select the application or service to allow or block. 
The list displays several common services, but you are not limited to th\
ese choices. To  add any additional services or applications that are not in the list, se\
lect  User Defined.
6.  If you know that the application uses either 
 TCP or UDP, select the appropriate protocol. If 
you are not sure, select  Both.
7.  Enter the starting and ending port numbers. 
If the application uses a single port number, enter that number in both fields. 
						

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8. Select the radio button for the IP address configuration you want to block, and enter the IP 
addresses. 
You can block the specified service for a single computer, a range of computers with 
consecutive IP addresses, or all computers on your network.
9. Click Add.
Your changes are saved. 
Port Triggering to Open Incoming Ports
Some application servers (such as FTP and IRC servers) send replies to multiple port 
numbers. Using the port triggering function of your router, you can tell the router to open 
more incoming ports when a particular outgoing port originates a session.
An example is Internet Relay Chat (IRC). Your computer connects to an IRC server at 
destination port 6667. The IRC server not only responds to your originating source port, but 
also sends an “identify” message to your computer on port 113. Using port triggering, you can 
tell the router, “When you initiate a session with destination port 6667, you have to also allow 
incoming traffic on port 113 to reach the originating computer.” 
Using steps similar to the preceding example, the following sequence shows the effects of 
the port triggering rule you have defined:
1. You open an IRC client program to start a chat session on your computer. 
2. Your IRC client composes a request message to an IRC server using a destination port 
number of 6667, the standard port number for an IRC server process. Your computer then 
sends this request message to your router.
3. Your router creates an entry in its internal session table describing this communication 
session between your computer and the IRC server. Your router stores the original 
information, performs Network Address Translation (NAT) on the source address and port, 
and sends this request message through the Internet to the IRC server. 
4. Noting your port triggering rule and having observed the destination port number of 6667, 
your router creates an additional session entry to send any incoming port 113 traffic to your 
computer.
5. The IRC server sends a return message to your router using the NAT-assigned source port 
(for example, port 33333) as the destination port. The IRC server also sends an “identify” 
message to your router with destination port 113.
6. Upon receiving the incoming message to destination port 33333, your router checks its 
session table for an active session for port number 33333. IF so, the router restores the 
original address information replaced by NAT and sends this reply message to your 
computer.
7. Upon receiving the incoming message to destination port 113, your router checks its session 
table and finds an active session for port 113, associated with your computer. The router 
replaces the message’s destination IP address with your computer’s IP address and 
forwards the message to your computer. 
						

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8. When you finish your chat session, your router eventually senses a period of inactivity in the 
communications. The router then removes the session information from its session table, 
and incoming traffic is no longer accepted on port numbers 33333 or 113.
To configure port triggering, you need to know which inbound ports the application needs. 
Also, you need to know the number of the outbound port that triggers the opening of the 
inbound ports. You can usually determine this information by contacting the publisher of the 
application or the relevant user groups or news groups.
Only one computer at a time can use the triggered application.
Port Forwarding to Permit External Host Communications
In both of the preceding examples, your computer initiates an application session with a 
server computer on the Internet. However, you might need to allow a client computer on the 
Internet to initiate a connection to a server computer on your network. Normally, your router 
ignores any inbound traffic that is not a response to your own outbound traffic. You can 
configure exceptions to this default rule by using the port forwarding feature. 
A typical application of port forwarding can be shown by reversing the client-server 
relationship from the previous web server example. In this case, a remote computer’s 
browser needs to access a web server running on a computer in your local network. Using 
port forwarding, you can tell the router, “When you receive incoming traffic on port 80 (the 
standard port number for a web server process), forward it to the local computer at 
192.168.1.123.” The following sequence shows the effects of the port forwarding rule you 
have defined:
1. The user of a remote computer opens a browser and requests a web page from 
www.example.com, which resolves to the public IP address of your router. The remote 
computer composes a web page request message with the following destination 
information: 
Destination address. The IP address of www.example.com, which is the address of your 
router.
Destination port number. 80, which is the standard port number for a web server 
process.
The remote computer then sends this request message through the Internet to your 
router.
2. Your router receives the request message and looks in its rules table for any rules covering 
the disposition of incoming port 80 traffic. Your port forwarding rule specifies that incoming 
port 80 traffic should be forwarded to local IP address 192.168.1.123. Therefore, your router 
modifies the destination information in the request message:
The destination address is replaced with 192.168.1.123.
Your router then sends this request message to your local network.
3. Your web server at 192.168.1.123 receives the request and composes a return message 
with the requested web page data. Your web server then sends this reply message to your 
router. 
						

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4. Your router performs Network Address Translation (NAT) on the source IP address, and 
sends this request message through the Internet to the remote computer, which displays the 
web page from www.example.com.
To configure port forwarding, you need to know which inbound ports the application needs. 
You can usually find this information by contacting the publisher of the application or the 
relevant user groups or news groups.
How Port Forwarding Differs from Port Triggering
The following points summarize the differences between port forwarding and port triggering:
•Any computer on your network can use port triggering, but only one computer can use it 
at a time.
•Port forwarding is allowed only for the computer that you specify on your network.
•With port triggering, you do not need to specify the computer’s IP address. The IP 
address is captured automatically.
•Port forwarding requires that you specify the computer’s IP address during configuration, 
and the IP address can never change.
•Port triggering requires specific outbound traffic to open the inbound ports, and the 
triggered ports are closed after a period of no activity.
•Port forwarding is always active and does not need to be triggered.
Set Up Port Forwarding to Local Servers
The port forwarding feature lets you allow certain types of incoming traffic to reach servers on 
your local network. For example, you might want to make a local web server, FTP server, or 
game server visible and available to the Internet.
Use the Port Forwarding/Port Triggering screen to configure the router to forward specific 
incoming protocols to computers on your local network. In addition to servers for specific 
applications, you can also specify a default DMZ server to which all other incoming protocols 
are forwarded.
Before you start, determine which type of service, application, or game you want to provide, 
and the local IP address of the computer that will provide the service. The server computer 
has to always have the same IP address.
To ensure that your server computer always has the same IP address, use the reserved IP 
address feature of your product. See 
Address Reservation on page 36. 
						

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To forward specific incoming protocols:
1. 
Select  Advanced > 
 Advanced Setup > Port Forwarding/Port Triggering .
2. Leave the  Port Forwarding  radio button selected as the service type.
3.  In the Service Name list, select the service name.
If the service is not in the list, see Add a Custom Service on page  75
4.  Fill in the Server IP 
 Address field
5.  Click  Add.
The list now includes the service.
Add a Custom Service
To define a service, game, or application that is not in the Service Name\
 list, first determine 
which port number or range of numbers the application uses. You can usually determine this 
information by contacting the publisher of the application or user group\
s or news groups. 
When you have the port number information, follow these steps.
To add a custom service:
1.  Select  Advanced > 
 Advanced Setup > Port Forwarding/Port Triggering .
2.  Select the Port Forwarding radio button as the service type. 
						

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3. 
Click the  Add Custom Service  button.
4. In the Service Name field, enter a descriptive name. 
5.  In the Service 
 Type field, select the protocol. If you are unsure, select  TCP/UDP.
6.  In the Eternal Starting Port field, enter the beginning port number
 . 
• If the application uses a single port, enter the same port number in the\
 Ending Port 
field.
• If the application uses a range of ports, enter the ending port number o\
f the range in 
the External Ending Port field.
7.  Fill in the Internal IP address field or select the radio button from th\
e list of currently attached 
devices.
8.  Click  Apply . 
The service is now included in the list.
Edit or Delete a Port Forwarding Entry
To edit or delete a port forwarding entry:
1.  Select  Advanced > 
 Advanced Setup > Port Forwarding/Port Triggering .
2.  Select the  Port Forwarding radio button as the service type
3.  In the table, select the radio button next to the service name.
4.  Click  Edit Service or  Delete Service.
Application Example: Make a Local Web Server Public
If you host a web server on your local network, you can use port forward\
ing to allow web 
requests from anyone on the Internet to reach your web server. 
To make a local web server public:
1. Assign your web server either a fixed IP address or a dynamic IP address\
 using DHCP 
address reservation. 
In this example, your router always gives your web server an IP address \
of 192.168.1.33.  
						

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2. In the Port Forwarding/Port Triggering screen, configure the router to forward the HTTP 
service to the local address of your web server at 192.168.1.33. 
HTTP (port 80) is the standard protocol for web servers.
3. (Optional) Register a host name with a Dynamic DNS service, and configure your router to 
use the name. 
To access your web server from the Internet, a remote user has to know the IP address 
that your ISP assigned. However, if you use a Dynamic DNS service, the remote user can 
reach your server by a user-friendly Internet name, such as mynetgear.dyndns.org.
Set Up Port Triggering
Port triggering is a dynamic extension of port forwarding that is useful in these cases:
•More than one local computer needs port forwarding for the same application (but not 
simultaneously).
•An application needs to open incoming ports that are different from the outgoing port.
When port triggering is enabled, the router monitors outbound traffic looking for a specified 
outbound “trigger” port. When the router detects outbound traffic on that port, it remembers 
the IP address of the local computer that sent the data. The router then temporarily opens the 
specified incoming port or ports and forwards incoming traffic on the triggered ports to the 
triggering computer. 
Port forwarding creates a static mapping of a port number or range to a single local 
computer. Port triggering can dynamically open ports to any computer that needs them and 
can close the ports when they are no longer needed.
Note:If you use applications such as multiplayer gaming, peer-to-peer 
connections, real-time communications such as instant messaging, or 
remote assistance (a feature in Windows XP), you should also enable 
Universal Plug and Play (UPnP).
To configure port triggering, you need to know which inbound ports the application needs, 
and the number of the outbound port that triggers the opening of the inbound ports. You can 
usually determine this information by contacting the publisher of the application or user 
groups or news groups.
To enable port triggering: 
1. Select Advanced > Advanced Setup > Port Forwarding/Port Triggering. 
						

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2. 
Select the  Port Triggering radio button.
3. Clear the Disable Port Triggering check box.
Note: If the Disable Port Triggering check box is selected after you configure 
port triggering, port triggering is disabled. However, any port triggering 
configuration information you added to the router is retained even 
though it is not used.
4.  In the Port 
 Triggering Timeout field, enter a value up to 9999 minutes. 
This value controls the inactivity timer for the designated inbound port\
s. The inbound  ports close when the inactivity time expires. 
 This is required because the router cannot be 
sure when the application has terminated.
To add a port triggering service:
1.  On the Port 
 Triggering screen, click  Add Service.
2. In the Service Name field, type a descriptive service name. 
3.  In the Service User list, select  Any
 , or select Single address and enter the IP address of 
one computer.
• Any (the default), allows any computer on the Internet to use this ser\
vice.  
						

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•
Single address restricts the service to a particular computer. 
4.  Select the service type, either  TCP or UDP or both (TCP/UDP). If you are not sure, select 
TCP/UDP
 .
5.  In the 
Triggering Port field, enter the number of the outbound traffic port to open the ause 
the inbound ports to be opened. 
6.  Enter the inbound connection port information in the Connection 
 Type, Starting Port, and 
Ending Port fields.
7.  Click  Apply .
The service is added in to the Portmap Table. 
8.  Make sure that you enable port triggering so that the service that you a\
dded takes 
ef

fectwillis used.
Schedule Blocking
You can specify the days and time that you want to block Internet access.\
To schedule blocking:
1. Select  Advanced > Security > Schedule .
2. Set up the schedule for blocking keywords and services.
• Days to Block . Select days on which you want to apply blocking by selecting the 
appropriate check boxes, or select Every Day to select the check boxes for all days. 
• T
ime of Day to Block. Select a start and end time in 24-hour format, or select  All 
Day for 24-hour blocking.  
						

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3. 
Select your time zone from the list. If you use daylight savings time, s\
elect the 
Automatically adjust for daylight savings time  check box. 
4.  Click  Apply . 
Your settings are saved.
Security Event Email Notifications
To receive logs and alerts by email, provide your email information in th\
e E-mail screen, and  specify which alerts you want to receive and how often. 
To set up email notifications:
1.  Select  Advanced > Security >  E-mail.
2. Select the  Turn Email Notification On  check box.
3.  In the 
Your Outgoing Mail Server field, enter the name of your ISP’s outgoing (SMTP) mail 
server (such as mail.myISP.com). 
You might be able to find this information in the configuration screen of\
 your email  program. If you leave this field blank, log and alert messages are not s\
ent.
4.  Enter the email address to which logs and alerts are sent in the Send to\
 
 This Email Address 
field. 
This email address is also used for the From address. If you leave this \
field blank, log and  alert messages are not sent.
5.  If your outgoing email server requires authentication, select the  My Mail Server requires 
authentication  check box. Fill in the User Name and Password fields for the outgoing e\
mail 
server

.
6.  (Optional) Select the  Send Alerts 
 Immediately check box.
Email alerts are sent immediately when someone attempts to visit a block\
ed site.