Periodic Internet outages when bypassing Telus router

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Just wanted to get something on the forum that might be a benefit to others running into the situation I've run into with a number of Telus business and home clients. The problem occurs when you want to bypass the ActionTec router that Telus provides and use your own. The ActionTec can either be in bridge mode or removed from the circuit completely and firewall/router duties replaced by your own on-premises device. In our case, all the affected circuits had the ActionTec replaced by Sonicwall firewalls. The main symptom is that the connection appears to drop periodically and no traffic is received by your on-premises firewall from the Telus gateway. Monitoring the connection showed that the connection would go down every 37 minutes precisely from the time it was reset (a simple unplug of the Internet cable usually did the trick). If left on its own, the connection would resume 2 hours and 53 minutes later, and the cycle would continue. Telus support was of no help at all, unsurprisingly, but analyzing packet captures revealed unusual ARP (Address Resolution Protocol) behavior. Sonicwall support confirmed that the problem was a "non-standard implementation of ARP". When I contacted Telus, they eventually confirmed that ARP was disabled on the circuit and is disabled on every circuit that the ActionTec T3200H router is deployed on. After Telus enabled ARP on the circuit, the connection stabilized completely. ARP is an essential last hop protocol and should never be disabled but, for some reason, Telus chooses to disable it. Consequently, it causes drop-out problems in moderately more sophisticated home and business environments that need more functionality than the simple ActionTec modem provides. Note that Telus will enable ARP on a business service but will not on a residential service, so in that case you're stuck with the ActionTec modem. Normally this is not a problem, but if you need more sophisticated services such as a VPN, you're simply out of luck. The only solution for a home user is to upgrade your circuit to business and have Telus enable ARP. I suppose you could downgrade to residential without losing the ARP setting but haven't tried. Hope this saves someone from the hours of work I had to do to figure it out. Telus was of very little help, sadly but unsurprisingly.