User manual

5352

Advanced Setup Method

section

The VoIP Router’s firewall enables access control of client PCs,

blocks common hacker attacks, including IP Spoofing, Land Attack,

Ping of Death, IP with zero length, Smurf Attack, UDP port loopback,

Snork Attack, TCP null scan, and TCP SYN flooding. The firewall does

not significantly affect system performance and we advise leaving it

enabled to protect your network.

Note: After you check the radio button in the “Enable or disable

Firewall features” field, you must click the “SAVE SETTINGS” button

to display the list of firewall features.

Access Control

Access Control allows users to define the outgoing traffic permitted

or not-permitted through the WAN interface. In the example above, all

incoming and outgoing emails are blocked. The default is to permit all

outgoing traffic. (See the following page for details.)

The VoIP Router can also limit the access of hosts within the local

area network (LAN). The MAC Filtering Table allows the VoIP Router

to enter up to 32 MAC addresses that are not allowed access to the

WAN port.

Parameter Description

Flags: Indicates the route status:

C = Direct connection on the same subnet.

S = Static route.

R = RIP (Routing Information Protocol) assigned route.

I = ICMP (Internet Control Message Protocol) Redirect route.

Network Address: Destination IP address.

Netmask: The subnetwork associated with the destination.

This is a template that identifies the address bits in the destination

address used for routing to specific subnets. Each bit that

corresponds to a “1” is part of the subnet mask number; each bit that

corresponds to “0” is part of the host number.

Gateway: The IP address of the router at the next hop to which

frames are forwarded.

Interface: The local interface through which the next hop of this route

is reached.

Metric: When a router receives a routing update that contains a new or

changed destination network entry, the router adds 1 to the metric value

indicated in the update and enters the network in the routing table.

Firewall