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What is multicast communication?
Multicast is the communication where one host sends data to multiple hosts at once. The principle is that the sender of data sends each packet only once to reach all the members of the multicast group. The Transport Protocol most often used for multicast communication is User Datagram Protocol (UDP).
What is multicast issue?
Core Issue The most common issue in a multicast network is packets transmitted by the source not reaching receivers. Other issues could be related to the formation of the distribution tree itself, and unwanted flooding in LAN environments that use switches.
Should a small company block multicast on their network?
Currently, the firewall at a small company is blocking multicast on their network. Should they continue to block multicast? Are there security concerns to unblocking it? Are there benefits to unblocking it?
What is the IP address for IP multicast?
IP multicast traffic groups are identified by IP addresses in the range of 224.0.0.0 to 239.255.255.255 and incoming IGMP packets intended for reserved, or “well-known” multicast addresses automatically flood through all ports (except the port on which the packets entered the switch).
How to block port unicast and multicast flood blocking?
Step 1 Switch# configure terminal Enters global configuration mode. Step 2 Switch(config)# interface interface-id Enters interface configuration mode and enter the type and number of the switchport interface (for example, GigabitEthernet 1/1). Step 3 Switch(config-if)# switchport block multicast Blocks unknown multicast forwarding to the port.
Is it safe to block multicast at the border?
Blocking Multicast at the border has some good things going for it. Blocking it internally I personally don’t agree with. This is an opinion. Here’s a SANS article that might shed some light into Multicast security concerns.