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AT-IFS802SP/POE(W)-80 User Manual
Set up the COS priority level. With the drop-down selection item of 
Priority Type above being 
selected as COS only/COS first, this control item will then be available to set the queuing policy
for each port.
COS priority
: Set up the COS priority level 0~7 - High, Middle, Low, Lowest.
Click            .
6.21.3 COS Configuration
Apply
Set  up  the TOS  priority. With  the  drop-down  selection  item  of
 Priority Type above being 
selected as TOS only/TOS first, this control item will then be available to set the queuing policy
for each port.
TOS priority
: The system provides 0~63 TOS priority level. Each level has 4 types of 
priority—High, Middle, Low, and Lowest. The default value is ‘Lowest’ priority for each
level. When the IP packet is received, the system will check the TOS level value in the IP 
packet that has received. For example, the user sets the TOS level 25 as high, the system 
will check the TOS value of the received IP packet. If the TOS value of received IP packet 
is 25 (priority = high), and then the packet priority will have highest priority.
Click to have the configuration take effect..
6.21.4 TOS Configuration
Apply
6.22 IGMP Configuration
The Internet Group Management Protocol (IGMP) is an internal protocol of the Internet Protocol 
(IP) suite. IP manages multicast traffic by using switches, routers, and hosts that support IGMP. Enabling
IGMP allows the ports to detect IGMP queries, report packets, and manage IP multicast traffic through
the switch. IGMP have three fundamental types of message shown as follows:
Message
Description
Query
A message sent from the querier (IGMP router or switch) asking for a response 
from each host belonging to the multicast group.
Report
A message sent by a host to the querier to indicate that the host wants to be or 
is a member of a given group indicated in the report message.
Leave Group
A message sent by a host to the querier to indicate that the host has quit being a 
member of a specific multicast group.