RuggedCom RS8000 Manual Do Utilizador

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RuggedSwitch
™ User Guide 
Source Port 
This is the port receiving the multicast stream as described by this entry.  Source 
port information will be aged out after about two query intervals.  
Note:
 The switch can detect only one multicast traffic source at any one time.  The switch will 
display information about the first source it detects.  If a detected multicast traffic source 
“moves” to a different port (or another source of the same group becomes active) the switch will 
re-detect it after multicast source port information is aged out (about two query intervals later).     
Joined Ports 
These are the ports that have subscribed (with joins) to the source port’s traffic. 
Joined ports will be aged out, if no IGMP join messages are received by those 
ports for a certain amount of time (about 2 query intervals). 
Router Ports 
These are ports that connect to multicast routers.  These ports must receive the 
multicast streams in order to have the potential of distributing them to more 
distant hosts.  Dynamically discovered router ports will be aged out if no 
appropriate multicast router traffic is received on those ports (after about 2 query 
intervals). 
MAC Address 
The MAC address corresponds to the multicast group address.  The addresses are 
related in the following fashion: 
 
Multicast address W.X.Y.Z <-> MAC address 01-00-5E-XX-YY-ZZ 
 
where XX, YY and ZZ are simply X, Y and Z coded in hexadecimal 
Astute readers will have noted that addresses such as 224.1.1.1 and 225.1.1.1 will 
both map onto the same MAC address (01-00-5E-01-01-01).  This is indeed a 
problem for which the IEEE Network Working Group currently has no solution.  
Users are advised to be aware of and avoid this problem.
 
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