Allied Telesis AT-9724TS specifications Static Router Ports

Robustness Value

Last Member Query Interval

Host Timeout

Router Timeout

Leave Timer

Querier State

Querier Router Behavior

State

Adjust this variable according to expected packet loss. If packet loss on the VLAN is expected to be high, the Robustness Variable should be increased to accommodate increased packet loss.This entry field allows an entry of 1 to 255. Default = 2.

This field specifies the maximum amount of time between group-specific query messages, including those sent in response to leave group messages. Default = 1.

This is the maximum amount of time in seconds allowed for a host to continue membership in a multicast group without the Switch receiving a host membership report. Default = 260.

This is the maximum amount of time in seconds a route is kept in the forwarding table without receiving a membership report. Default = 260.

This specifies the maximum amount of time in seconds between the Switch receiving a leave group message from a host, and the Switch issuing a group membership query. If no response to the membership query is received before the Leave Timer expires, the (multicast) forwarding entry for that host is deleted. Choose Enabled to enable transmitting IGMP Query packets or Disabled to disable.The default is Disabled. This read-only field describes the behavior of the router for sending query packets. Querier will denote that the router is sending out IGMP query packets. Non-Querierwill denote that the router is not sending out IGMP query packets.This field will only read Querier when the Querier State and the State fields have been Enabled.

Select Enabled to implement IGMP Snooping.This field is Disabled by default.

Click Apply to implement the new settings. Click the Show All IGMP Group Entries link to return to the Current IGMP Snooping Group Entries window.

Static Router Ports

A static router port is a port that has a multicast router attached to it. Generally, this router would have a connection to a WAN or to the Internet. Establishing a router port will allow multicast packets coming from the router to be propagated through the network, as well as allowing multicast messages (IGMP) coming from the network to be propagated to the router.

A router port has the following behavior:

•All IGMP Report packets will be forwarded to the router port.

•IGMP queries (from the router port) will be flooded to all ports.

•All UDP multicast packets will be forwarded to the router port. Because routers do not send IGMP reports or implement IGMP snooping, a multicast router connected to the router port of a Layer 3 switch would not be able to receive UDP data streams unless the UDP multicast packets were all forwarded to the router port.

A router port will be dynamically configured when IGMP query packets, RIPv2 multicast, DVMRP multicast or PIM-DM multicast packets are detected flowing into a port.

Open the IGMP folder and the click on the Static Router Ports Entry link to open the Current Static Router Ports Entries page, as shown below.

Figure 6- 19. Current Static Router Ports Entries window

The Current Static Router Ports Entries page (shown above) displays all of the current entries to the Switch's static router port table.To modify an entry, click the Modify button.This will open the Static Router Ports Settings page, as shown below.

Allied Telesyn AT-9724TS High-Density Layer 3 Stackable Gigabit Ethernet Switch 41