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Multicast statistics: Difference between revisions
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(Created page with "The Multicast module analyzes IGMP and MLD multicast management packets and shows detailed information about multicast groups and their members. IGMPv1, v2, v3 for IPv4 and I...") |
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* Join: A member joins a multicast group and is interested in receiving all traffic for that group. | * Join: A member joins a multicast group and is interested in receiving all traffic for that group. | ||
It is sent as a reply to a query or as soon as the member joins the group. For IGMPv3 and MLDv2, a join is a membership report with either an empty exclude list or a non-empty include list of sources that send packets to that multicast group. | :It is sent as a reply to a query or as soon as the member joins the group. For IGMPv3 and MLDv2, a join is a membership report with either an empty exclude list or a non-empty include list of sources that send packets to that multicast group. | ||
* Leave: A member is no longer interested in receiving traffic for that group and sends a leave message (IGMPv2 and MLDv1) or a membership report (IGMPv3 and MLDv2). | * Leave: A member is no longer interested in receiving traffic for that group and sends a leave message (IGMPv2 and MLDv1) or a membership report (IGMPv3 and MLDv2). | ||
For IGMPv3 and MLDv2, a leave is a membership report with either an empty include list or a non-empty exclude list of sources that send packets to that multicast group. | :For IGMPv3 and MLDv2, a leave is a membership report with either an empty include list or a non-empty exclude list of sources that send packets to that multicast group. | ||
* Allow new source: A member adds new sources that send packets to a multicast group by sending a membership report. | * Allow new source: A member adds new sources that send packets to a multicast group by sending a membership report. | ||
If these sources are added in include mode, the member is interested in receiving packets from them and adds them to the include list. | :If these sources are added in include mode, the member is interested in receiving packets from them and adds them to the include list. If these sources are added in exclude mode, the member deletes them from the exclude list. Source lists were introduced with IGMPv3 and MLDv2. | ||
If these sources are added in exclude mode, the member deletes them from the exclude list. Source lists were introduced with IGMPv3 and MLDv2. | |||
* Block old source: A member blocks sources that send packets to a multicast group by sending a membership report. | * Block old source: A member blocks sources that send packets to a multicast group by sending a membership report. | ||
If these sources are blocked in include mode, the member does not want receiving packets from them and deletes them from the include list. | :If these sources are blocked in include mode, the member does not want receiving packets from them and deletes them from the include list. If these sources are blocked in exclude mode, the member adds them to the exclude list. Source lists were introduced with IGMPv3 and MLDv2. | ||
If these sources are blocked in exclude mode, the member adds them to the exclude list. Source lists were introduced with IGMPv3 and MLDv2. | |||
* Query: An IP multicast router queries the multicast reception state of neighbours with this message. | * Query: An IP multicast router queries the multicast reception state of neighbours with this message. | ||
Active multicast members will reply to the membership query with a proper membership report. | :Active multicast members will reply to the membership query with a proper membership report. Queries may be general, for a specific group or for a specific group with a specific source list. | ||
Queries may be general, for a specific group or for a specific group with a specific source list. | |||
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* Last multicast negotiation: The last seen IGMP or MLD message related to that member. | * Last multicast negotiation: The last seen IGMP or MLD message related to that member. | ||
* Last join: The time of the join or allow new source of the current session. | * Last join: The time of the join or allow new source of the current session. | ||
As those messages are repeated by the member, only the time of the first occurence of that message belonging to a session is shown. | :As those messages are repeated by the member, only the time of the first occurence of that message belonging to a session is shown. | ||
In case a new session starts, the leave time of an earlier session is not shown any longer. | :In case a new session starts, the leave time of an earlier session is not shown any longer. | ||
* Last join duration: The duration between the first join message and the first traffic for that multicast group address. | * Last join duration: The duration between the first join message and the first traffic for that multicast group address. | ||
IGMP/MLD messages for that group are not counted as traffic. If there is no traffic for that group after the join and a leave, a | :IGMP/MLD messages for that group are not counted as traffic. If there is no traffic for that group after the join and a leave, a '''-''' sign is shown. | ||
* Average join duration: The average of all join durations. | * Average join duration: The average of all join durations. | ||
* Last leave: The time of the leave or block old source of the last session. | * Last leave: The time of the leave or block old source of the last session. | ||
As those messages are repeated by the member, only the time of the first | :As those messages are repeated by the member, only the time of the first occurrence of that message belonging to a session is shown. | ||
* Last leave duration: The duration between the first leave message and the last traffic for that multicast group. IGMP/MLD messages for that group are not counted as traffic. | * Last leave duration: The duration between the first leave message and the last traffic for that multicast group. IGMP/MLD messages for that group are not counted as traffic. | ||
If there is traffic for that multicast group, the duration is calculated and refreshed. After a timeout of 60 seconds, if there is still traffic, the measurement is stopped and a duration of | :If there is traffic for that multicast group, the duration is calculated and refreshed. After a timeout of 60 seconds, if there is still traffic, the measurement is stopped and a duration of '''>60 seconds''' is displayed. This is quite common for e.g. Multicast DNS (group 224.0.0.251 and ff02::fb) or time synchronisation services such as PTP with lots of members. If there is no traffic for that group after the leave att all, a '''-''' sign is displayed. | ||
* Average leave duration: The average of all leave durations. | * Average leave duration: The average of all leave durations. | ||
* Graph: The history graph shows IGMP and MLD messages over time. | * Graph: The history graph shows IGMP and MLD messages over time. | ||
* PCAP: The PCAP button allows capturing all IGMP and MLD messages related to that specific member. | * PCAP: The PCAP button allows capturing all IGMP and MLD messages related to that specific member. | ||