VPort 25 User’s Manual
System Configuration
4-16
NOTE
Different DDNS service providers have different application rules. Some applications are free of
charge, but most require an application fee.
Universal PnP
UPnP (Universal Plug & Play)
is a networking architecture that provides compatibility among
networking equipment, software, and peripherals of the 400+ vendors that are part of the Universal
Plug and Play Forum. This means that they are listed in the network devices table for the operating
system (such as Windows XP) supported by this function. Users can link to VPort directly by
clicking on the VPort listed in the network devices table.
Setting
Description
Default
Enable UPnP
Enable or disable the UPnP function.
disable
Multicast
The VPort 25 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 belong 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:
y
Enables the simultaneous delivery of information to many receivers in the most efficient,
logical way.
