Delta DVPEN01-SL, Руководство по эксплуатации

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Ethernet Communication Module DVPEN01-SL
DVP-PLC Operation Manual
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5.9 IP Filter
An IP filter is used for restricting the connection of the network in case some uncertain IP addresses will cause errors.
Only the IP addresses set within a certain range can establish a connection. Other IP addresses will be rejected.

Setting an IP filter
1. Enable IP Filter
Check the box to enable IP filter.
2. IP Address
IP addresses that are allowed to establish connections. Maximum 8 IP addresses are allowed.
3. Subnet Netmask
The subnet of the IP adrress is allowed to establish a connection. To see whether the destination IP address
is allowed, conduct bitwise AND operations between the allowed IP address and subnet mask and
destination IP address and subnet mask. If the two values obtained are the same, the destination IP
address is allowed by the IP filter. For example, assume the IP address is 192.168.0.1 and subnet mask
255.255.255.255, the only one IP address allowed to establish a connection is 192.168.0.1. If the subnet
mask is 255.255.255.0, the IP addresses s allowed to establish connections will become
192.168.0.0~192.168.0.255.
5.10 Static ARP Table
ARP (Address Resolution Protocol) is used for obtaining the MAC address corresponding to the IP address in data
transmission. For example, there is a datum to be sent to 172.16.155.250, but you do not know the corresponding
MAC address. You can use ARP to look up the MAC address by IP address, and the corresponding MAC address will
be saved, so you do not need to look it up again when sending the next datum. Therefore, if you do not know the MAC
address, you will have to spend some time looking up the MAC address. If you want to enhance the transmission
efficiency, use static ARP table to save time. For example, assume the IP address is 192.168.0.1 and MAC is
00:14:22:56:0F:7F. As long as there are data sent to 192.168.0.1, you will get the MAC address from the table.