Number of users per slave, Network mitigation, Televes – Televes Coaxdata 1Gbps-HDTV COAX+PLC 1ETH+1SFP User Manual
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Televes
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If you have not installed an IGMP Querier in video distribution, or do not want the streams are
eliminated after the expiration, disable timers through the checkboxes in the application.
No purpose of this manual is to define the IGMP protocol or the
elements that comprise it. For details refer to the standards defined in
this regard:
GMPv2 and
IGMPv3
It is recommended not disable timers unless the system do not support
IGMPv3 (only support the old IGMPv2). In practice, if disable timers
then when device does not indicate that leaves a channel (IGMP leave)
by switching channels or disconnected abruptly, he still remains
member of channel with the consequent consumption of bandwidth.
Additionally, you can configure a number of parameters associated with IGMP:
Forward Unknown/Unmanaged Streams
: All multicast streams are transmitted from the
master to the slave even if no one registered in them. Since there is no list of registered devices
in each multicast, master uses a very conservative modulation which results in excessive
bandwidth consumption. This modulation is named ROBO (ROBust mOdulation) and transmits
a maximum of 5Mbps to all devices on netwok.
It is not recommended to use this option
unless you really know what you are doing.
IGMP Reports to Non-Querier Hosts
: By default, IGMP reports only are sent to Ethernet ports
if IGMP Querier exists on network, ie, IGMP reports are sent to querier. When this option is
enabled allows resend all IGMP join/leaves to Ethernet ports even if IGMP Queriers are not
present (ie , Multicast routers or switches connected to the Master). This allows IGMP reports
are propagate to network even when no multicast IGMP Queriers exists, but STB periodically
send IGMP messages indicated their intention to belong to a specific multicast group.
Although it is possible to implement videostreaming systems that do not require the existence of IGMP
Queriers, Installer is recommended to implement an IGMP querier, with a multicast router or a switch,
so as to provide an automated management and that guarantees that the bandwidth is used only when
users actually want to use video services and releasing those resources when leaving a channel.
Number of Users per Slave
When coaxial data network is implemented in community facilities, is very useful to limit the number of
users for each slave, since customers in their homes can use more than one device. This also
increases engine performance of the system, since it limits the number of links in the system:
•
MAC Address Limit
: This option sets a limit on the number of hosts connected to MAC
Ethernet ports that a device supports. This option can be used by installers of hotels, buildings,
who want to limit the number of users who use the data service from the slaves and allows
control on the number of total users that will use the data network.
•
Bridge Address Aging
: Set the timer used to determine when an entry in the local table
(associated with Ethernet hosts) or a remote table (where hosts are picked from other devices
on the network) is invalid or has expired .
Network Mitigation
Normally in a network of one master and several slaves they transmit at maximum power in order to
ensure greater coverage and throughput. It is possible that in a coaxial network are installed two
different networks, with two masters and their slaves are poorly insulated from each other or the
insulation provided by the network is not sufficient and interference occurs between adjacent networks
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