Chapter 12 Interfaces

 

 

 

 

Table 68 Configuration > Network > Interface > PPP > Add (continued)

 

LABEL

DESCRIPTION

 

MTU

Maximum Transmission Unit. Type the maximum size of each data packet, in bytes, that

 

 

can move through this interface. If a larger packet arrives, the ISG50 divides it into

 

 

smaller fragments. Allowed values are 576 - 1492. Usually, this value is 1492.

 

 

 

 

Connectivity Check

The interface can regularly check the connection to the gateway you specified to make

 

 

sure it is still available. You specify how often the interface checks the connection, how

 

 

long to wait for a response before the attempt is a failure, and how many consecutive

 

 

failures are required before the ISG50 stops routing to the gateway. The ISG50

 

 

resumes routing to the gateway the first time the gateway passes the connectivity

 

 

check.

 

 

 

 

Enable

Select this to turn on the connection check.

 

Connectivity

 

 

Check

 

 

 

 

 

Check Method

Select the method that the gateway allows.

 

 

Select icmp to have the ISG50 regularly ping the gateway you specify to make sure it

 

 

is still available.

 

 

Select tcp to have the ISG50 regularly perform a TCP handshake with the gateway you

 

 

specify to make sure it is still available.

 

 

 

 

Check Period

Enter the number of seconds between connection check attempts.

 

 

 

 

Check Timeout

Enter the number of seconds to wait for a response before the attempt is a failure.

 

 

 

 

Check Fail

Enter the number of consecutive failures before the ISG50 stops routing through the

 

Tolerance

gateway.

 

 

 

 

Check Default

Select this to use the default gateway for the connectivity check.

 

Gateway

 

 

 

 

 

Check this

Select this to specify a domain name or IP address for the connectivity check. Enter

 

address

that domain name or IP address in the field next to it.

 

 

 

 

Check Port

This field only displays when you set the Check Method to tcp. Specify the port

 

 

number to use for a TCP connectivity check.

 

 

 

 

Related Setting

 

 

 

 

 

Configure WAN

Click WAN TRUNK to go to a screen where you can configure the interface as part of a

 

TRUNKWAN trunk for load balancing.

 

 

 

 

Policy Route

Click Policy Route to go to the screen where you can manually configure a policy route

 

 

to associate traffic with this interface.

 

 

 

 

OK

Click OK to save your changes back to the ISG50.

 

 

 

 

Cancel

Click Cancel to exit this screen without saving.

 

 

 

12.5 Cellular Configuration Screen (3G)

3G (Third Generation) is a digital, packet-switched wireless technology. Bandwidth usage is optimized as multiple users share the same channel and bandwidth is only allocated to users when they send data. It allows fast transfer of voice and non-voice data and provides broadband Internet access to mobile devices.

Note: The actual data rate you obtain varies depending on the 3G card you use, the signal strength to the service provider’s base station, and so on.

You can configure how the ISG50’s 3G device connects to a network (refer to Section 12.5.1 on page 253):

 

251

ISG50 User’s Guide