I have an ASUS RT-AC68R (as well as an RT-AC66R). I noticed that both of these routers appear to be broadcasting something over the network every 2 seconds. I don't have any network monitoring tools but I suspect that what I am seeing is some form of RSTP protocol that is sending out a "hello" message every two seconds. I explain why I am saying this later in the post. Both the RT-AC68R and RT-AC66R appear to be working just fine and are on the latest firmware version 3.0.0.4.374_5517 (downloaded from ASUS). This 2-second broadcast is not firmware version related - both routers have done this from day 1.
The scenario: With just about all extra functionality disabled on my RT-AC68R - and Netgear switches attached to two of the LAN ports - I see LED activity blinking on the switches every two seconds (with no devices attached to the switches). If I add devices to the switches - I see the 2-second activity blinking on every port of of both switches to which an active device is attached - even though those devices are "idle". This is telling me that the router is sending out a broadcast every two seconds - to every device on the LAN. If I swap out the ASUS RT-AC68R (or RT-AC66R) for another non-ASUS router - I do not see the 2-second broadcast on any of the switches and I only see LED activity for devices that are actively transmitting. One of my other routers allows me to selectively enable RTSP on a per-port basis. When I enable RTSP - there are several RSTP specific parameters - one of which is a "Hello" interval - which defaults to 2-seconds. With RTSP enabled (on the non-Asus router) - I see the same 2-second broadcast on my switches - that I see "all the time" with the ASUS RT-AC68R and RT-AC66R. If I use a non-ASUS router (such as an Apple Airport Extreme) which does not support RSTP - but I enable the network loop checking functionality on one of my NETGEAR managed switches - I again see the the 2-second broadcast activity across my entire network. This is telling me that the RT-AC68R and RT-AC66R are constantly running an RSTP-like protocol - with no configuration option to enable or disable it.
It is my understanding that RSTP is used primarily in enterprise networks where there is a heavy use of VLANs and RTSP is needed in those scenarios to automatically detect topology changes in the network - as well as providing some type of network loop prevention. In a home network - there is going to be very little change to the network topology - and not a lot of VLAN use - therefore - it seems that this 2-second broadcast is just creating unnecessary activity on the LAN. I probably would not have noticed this had I not had switches attached to each LAN port on the RT-AC68R.
I have asked ASUS tech support about this - and they can't seem to answer my question - and don't seem to know what I am asking when I mention that this activity seems to be unusual and has me concerned.
Has anybody experienced this broadcast activity and can somebody explain what it is - and whether or not is is a problem?
The scenario: With just about all extra functionality disabled on my RT-AC68R - and Netgear switches attached to two of the LAN ports - I see LED activity blinking on the switches every two seconds (with no devices attached to the switches). If I add devices to the switches - I see the 2-second activity blinking on every port of of both switches to which an active device is attached - even though those devices are "idle". This is telling me that the router is sending out a broadcast every two seconds - to every device on the LAN. If I swap out the ASUS RT-AC68R (or RT-AC66R) for another non-ASUS router - I do not see the 2-second broadcast on any of the switches and I only see LED activity for devices that are actively transmitting. One of my other routers allows me to selectively enable RTSP on a per-port basis. When I enable RTSP - there are several RSTP specific parameters - one of which is a "Hello" interval - which defaults to 2-seconds. With RTSP enabled (on the non-Asus router) - I see the same 2-second broadcast on my switches - that I see "all the time" with the ASUS RT-AC68R and RT-AC66R. If I use a non-ASUS router (such as an Apple Airport Extreme) which does not support RSTP - but I enable the network loop checking functionality on one of my NETGEAR managed switches - I again see the the 2-second broadcast activity across my entire network. This is telling me that the RT-AC68R and RT-AC66R are constantly running an RSTP-like protocol - with no configuration option to enable or disable it.
It is my understanding that RSTP is used primarily in enterprise networks where there is a heavy use of VLANs and RTSP is needed in those scenarios to automatically detect topology changes in the network - as well as providing some type of network loop prevention. In a home network - there is going to be very little change to the network topology - and not a lot of VLAN use - therefore - it seems that this 2-second broadcast is just creating unnecessary activity on the LAN. I probably would not have noticed this had I not had switches attached to each LAN port on the RT-AC68R.
I have asked ASUS tech support about this - and they can't seem to answer my question - and don't seem to know what I am asking when I mention that this activity seems to be unusual and has me concerned.
Has anybody experienced this broadcast activity and can somebody explain what it is - and whether or not is is a problem?
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