# IGMP Interfaces

Port > Configure > IGMP

The IGMP Interfaces dialog box lists all the multicast groups for which there are members on a particular interface.

To view the definition for a particular MIB variable, click the appropriate link from the following list:

- Membership (igmpCacheSelf)

- Last Reporter (igmpCacheLastReporter)

- Cache Up Time (igmpCacheUpTime)

- Expiry Time (igmpCacheExpiryTime)

- Version 1 Timer (igmpCacheVersion1HostTimer)

- Robustness (igmpInterfaceRobustness)

The following list specifies buttons in this dialog box, as well as their function:

- Click OK to continue.

- Click Apply to save the changes in the dialog box.

- Click Cancel to close the dialog box.

- Click Refresh to update the contents of the dialog box.

- Click Print to print the contents of the dialog box.

- Click Help to access online help.

Membership (igmpCacheSelf)

Indicates whether the local system is a member of this interface's group address.

Last Reporter (igmpCacheLastReporter)

IP address of the source of the last membership report received for this IP Multicast group address. If no membership report has been received, the value of this object is "0.0.0.0".

Cache Up Time (igmpCacheUpTime)

Amount of time since the system joined this group address. The value of this object is zero if the system is not currently a member of this group address.

Expiry Time (igmpCacheExpiryTime)

Amount of time that needs to pass before this entry is aged out.

Version 1 Timer (igmpCacheVersion1HostTimer)

Time remaining until the local router assumes that there are no longer any IGMP version 1 members on the IP subnet attached to this interface. After receiving an IGMPv1 membership report, this value of this object is reset to the group membership timer. Until the timer reaches zero, the local router ignores any IGMPv2 Leave messages received on this interface for this group.

Robustness (igmpInterfaceRobustness)

The robustness variable can be adjusted to deal with expected packet loss on a subnet. If a subnet is expected to be lossy, the robustness variable should be increased.