Recently, there has been some heat rising up because the users are reporting that they experience a connectivity problem with their Wi-Fi post installation of Chromecast and Home speaker. Some routers experience complete signal loss while some others become dysfunctional for very short time.
It should be noted that bug is not a router problem, rather it is a problem with the ‘Cast’ feature.
It was for the first when a user reported such a problem with his TP-Link Archer 1200 router on Google Product Forums.
Later on; engineers from TP-Link figured out that it was the issue with Cast feature as it sends multicast DNS (MDNS) packets to discover and maintain a live connection with all Google products.
Likely, MDNS is the issue
MDNS has the role of resolving hostnames or assigned network names of devices to IP addresses. This is very common across local networks without a DNS server. On general, every 20 seconds, a packet is sent.
Now, the problem with Google devices is that they send too many data packets in a very short span of time. This usually occurs when the device is woken up from the ‘sleep’ mode. The longer it stays in the sleep mode, the more number of packets it collects, and when you wake it; a large number of MDNS packets are sent to connect.
MDNS makes use of User Datagram Protocol (UDP) for sending information packets. Unfortunately, there is no congestion control on UDP therefore; a device with large number of packets can really turn things upside down easily in the pursuit of sending them.
The congestion causes the memory to stock up completely with MDNS packets. The user cannot do anything about it and ultimately the user has to reboot the router to get the internet connection back.
All the router manufacturers like TP-Link, Linksys, and Netgear have looked into the problem and provided the users with a firmware update. Though, the updates are not the complete solution they will just work until Google comes up with a patch for Cast.
Google stated that they are aware of the problem with the Cast feature. An update to the problem was rolled out via a Google Play Services update on 18 January, 2018.