CCIE RS Tips Summary - Multicast Overview
(1) Multicast solves the problem of an uncertain number of users in the network, one message, multiple receivers, and the same multicast data stream has at most one on each link. The schematic is as follows.
(2) Advantages and disadvantages of multicast
Advantages: Reduce server and CPU load, reduce the occupation of link bandwidth resources, and reduce the load on network devices.
Disadvantages: Multicast is based on UDP.
Try to deliver:
Message loss is inevitable. Therefore, the multicast application cannot rely on the multicast network for reliability guarantee, and must be specially designed for this feature of the multicast network. "Reliable Multicast" is still in the research stage.
No congestion avoidance mechanism:
Due to the lack of TCP window mechanism and slow start mechanism, multicast may be congested. If possible, the multicast application should try to detect and avoid congestion.
Repeat the message:
Certain mechanisms of some multicast protocols, such as the Assert mechanism and the SPT switching mechanism, may cause occasional packet duplication. Multicast applications should tolerate this phenomenon.
Message out of order:
Similarly, the multicast protocol sometimes causes the order of message arrival to be disordered. The multicast application must correct it by some means (such as the buffer pool mechanism, etc.).
(3) Three basic conditions for implementing multicast
Hardware facilities:
Multicast server
Network that supports multicast distribution
Client that can receive multicast streams
software technology:
Multicast address must exist
Must have support for multicast routing protocols
Clients must be free to join or leave the multicast group
CCIE RS basic of Cisco, if you want to pass CCIE Wireless exam that had better to review the CCIE Wireless 400-351 Dumps that will help you passed exam successfully. I strongly recommend the ccnp wireless 300 360 dumps to you that you can first step to ccie. All come from cisco tags.
(2) Advantages and disadvantages of multicast
Advantages: Reduce server and CPU load, reduce the occupation of link bandwidth resources, and reduce the load on network devices.
Disadvantages: Multicast is based on UDP.
Try to deliver:
Message loss is inevitable. Therefore, the multicast application cannot rely on the multicast network for reliability guarantee, and must be specially designed for this feature of the multicast network. "Reliable Multicast" is still in the research stage.
No congestion avoidance mechanism:
Due to the lack of TCP window mechanism and slow start mechanism, multicast may be congested. If possible, the multicast application should try to detect and avoid congestion.
Repeat the message:
Certain mechanisms of some multicast protocols, such as the Assert mechanism and the SPT switching mechanism, may cause occasional packet duplication. Multicast applications should tolerate this phenomenon.
Message out of order:
Similarly, the multicast protocol sometimes causes the order of message arrival to be disordered. The multicast application must correct it by some means (such as the buffer pool mechanism, etc.).
(3) Three basic conditions for implementing multicast
Hardware facilities:
Multicast server
Network that supports multicast distribution
Client that can receive multicast streams
software technology:
Multicast address must exist
Must have support for multicast routing protocols
Clients must be free to join or leave the multicast group
CCIE RS basic of Cisco, if you want to pass CCIE Wireless exam that had better to review the CCIE Wireless 400-351 Dumps that will help you passed exam successfully. I strongly recommend the ccnp wireless 300 360 dumps to you that you can first step to ccie. All come from cisco tags.
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