Wieland wienet v3, Руководство пользователя

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Contents of Package
41
Wieland Electric GmbH | BA001039 (Rev. A) | 08/2016
5.8 Firewall Configuration
The first security element which incoming packets must pass is check of enabled source IP addresses
and destination ports. It can be specified IP addresses from which you can remotely access the router
and the internal network connected behind a router. If the
Enable filtering of incoming packets
item is
checked (located at the beginning of the configuration form Firewall), this element is enabled and all in-
coming packets are checked against the table with IP addresses. This means that incoming packets will
be treated according rules specified in the table. It is possible to define up to eight rules for incoming
packets. There are the following parameters:
Item Description
Source IP address from which access to the router is allowed
Protocol Specifies protocol for remote access:
•
all – access is enabled for all protocols
•
TCP – access is enabled for TCP protocol
•
UDP – access is enabled for UDP protocol
•
ICMP – access is enabled for ICMP protocol
Target Port The port number on which access to the router is allowed
Action Type of action:
•
allow – access is allowed
•
deny – access is denied
Filtering of incoming packets
The following part of the configuration form defines the forwarding policy. If
Enabled filtering of for-
warded packets
item is not checked, packets will be accepted automatically. If this item is checked and
incoming packet is addressed to another network interface, it will forward the packet according the rules
defined in this second table. If the packet is alowed according to the table, it will be sent out according to
the routing table. If the forwarding rule does not exist, packet will be dropped.
In tables with rules it is possible to allow all traffic within the selected protocol (the rule specifies only a
protocol). Or you can create strict rules by specifying source and destination IP addresses and ports.
Item Description
Source IP address of source device
Destination IP address of destination device
Protocol Specifies protocol for remote access:
•
all – access is enabled for all protocols
•
TCP – access is enabled for TCP protocol
•
UDP – access is enabled for UDP protocol
•
ICMP – access is enabled for ICMP protocol
Target Port The port number on which access to the router is allowed
Action Type of action:
•
allow – access is allowed
•
deny – access is denied
Forwarding filtering
There is also the possibility to drop a packet whenever request for service which is not in the router
comes (check box named Enable filtering of locally destinated packets ). The packet is dropped automati-
cally without any information.
As a protection against DoS attacks (this means attacks during which the target system is flooded with
plenty of meaningless requirements) is used option named
Enable protection against DoS attacks
which
limits the number of connections to five per second.