UPnP port assignment leftovers on WNDR3700

[DemonRage]

While browsing through the router manager web page of my WNDR3700, I noticed that some UPnP port assignments stay assigned to clients that are already gone. I think that when those assignments are still in the table, the ports can never be assigned again through UPnP.

Is there a quick way, without resetting the router or temporarily disabling UPnP, to remove UPnP port assignments that aren't needed anymore? Or is there a validation mechanism that removes unused port assignments over time?

I hope that they implement something in future firmware releases that allows advanced users to manually remove unused UPnP port assignments to prevent the table from collecting a lot of them.

[jmizoguchi]

Advertisement Period

The Advertisement Period is how often the router will advertise (broadcast) its UPnP information. This value can range from 1 to 1440 minutes. The default period is for 30 minutes. Shorter durations will ensure that control points have current device status at the expense of additional network traffic. Longer durations may compromise the freshness of the device status but can significantly reduce network traffic.

Advertisement Time To Live

The time to live for the advertisement is measured in hops (steps) for each UPnP packet sent. A hop is the number of steps allowed to propagate for each UPnP advertisement before it disappears. The number of hops can range from 1 to 255. The default value for the advertisement time to live is 4 hops, which should be fine for most home networks. If you notice that some devices are not being updated or reached correctly, then it may be necessary to increase this value a little.

UPnP Portmap Table

The UPnP Portmap Table displays the IP address of each UPnP device that is currently accessing the router and which ports (Internal and External) that device has opened. The UPnP Portmap Table also displays what type of port is opened and if that port is still active for each IP address.

[DemonRage]

Originally Posted by jmizoguchi

Advertisement Period

The Advertisement Period is how often the router will advertise (broadcast) its UPnP information. This value can range from 1 to 1440 minutes. The default period is for 30 minutes. Shorter durations will ensure that control points have current device status at the expense of additional network traffic. Longer durations may compromise the freshness of the device status but can significantly reduce network traffic.

Advertisement Time To Live

That's not it. Advertisement notifies every client on the network about connected UPnP devices (like storage or media servers). It doesn't remove entries from the table if a client doesn't exist anymore i.e. a client that didn't send a del_nat_rule before leaving.

[jmizoguchi]

you might want to hit support. my.netgear.com

there is much you can do since it is a firmware function issues