Moxa VPort 26A-1MP
System Configuration
4-17
1st FTP Server
Setting
Description
Default
1st FTP server
FTP server’s IP address or URL address.
None
1st FTP server port
FTP server’s authentication.
None
1st FTP user name
None
1st FTP remote folder
FTP file storage folder on the remote FTP server.
None
1st FTP passive mode
Passive transfer solution for FTP transmission through a firewall.
Disabled
NOTE
The 2nd FTP Server is a backup in case the 1st FTP Server fails to connect or has trouble sending files.
NOTE
Whenever the system reboots, a system log will be sent by email or FTP to show the login status of the VPort.
The system log will be sent to the Sender email address if the SMTP server settings are correct. To send the
system log via FTP, the SMTP server should be erased since the E-mail system is used by default to transmit the
system log.
NOTE
For either e-mail or FTP, the information of the 1st server should be entered first. If the 1st server is not set,
the related FTP or email will be cancelled. Note that it may take time to connect to the 2nd server after the first
server fails, and this may affect some applications when adverse conditions occur too often.
Multicast
The VPort 26A-1MP supports the advanced Multicast network protocol IGMP, which can greatly improve the
efficiency of network traffic. In this section, we explain multicasts, multicast filtering, and how multicast can be
implemented on your VPort.
What is Multicast?
A multicast is a packet that is intended for “one-to-many” and “many-to-many” communication. Users
explicitly request to participate in the communication by joining an end-station to a specific multicast group. If
the network is set up correctly, a multicast can only be sent to an end-station or a subset of end-stations on a
LAN or VLAN that belongs to the relevant multicast group. Multicast group members can be distributed across
multiple subnetworks. Therefore, multicast transmissions can occur within a campus LAN or over a WAN. In
addition, networks that support IP multicast send only one copy of the desired information across the network.
The packets are only replicated if they reach a network node that links to two or more members of the multicast
network. Transmitting packets in this way makes more efficient use of network bandwidth. A multicast packet
is identified by the presence of a multicast group address in the destination address field of the packet’s IP
header.
Benefits of Multicast
The benefits of using IP multicast are that it:
•
Enables the simultaneous delivery of information to many receivers in the most efficient, logical way.
•
Reduces the load on the source (for example, a server) because it does not need to produce multiple copies
of the same data.
•
Makes efficient use of network bandwidth and scales well as the number of participants or collaborators
expands.
•
Works with other IP protocols and services, such as Quality of Service (QoS).
There are situations where a multicast approach is more logical and efficient than a unicast approach. A typical
use of multicasts is in video-conferencing, in which high volumes of traffic need to be sent to several
end-stations simultaneously, but for which broadcasting that traffic to all end-stations would seriously reduce
network performance. Several industrial automation protocols, such as Allen-Bradley, EtherNet/IP, Siemens
Profibus, and Foundation Fieldbus HSE (High Speed Ethernet), use the multicast approach. These industrial
Ethernet protocols use publisher/subscriber communications models by multicasting packets that could flood a
