Chad someone needs to make sure 6121 gets added to the supported modem list. No excuses! This is by far the best selling DOCSIS 3 modem on the market and the 6120 has not been available for months now. I swear I could work as a salesman for Motorola. I have recommended this modem to many customers. I mean with the prices people pay why pay a rental fee for a 10yr old piece of shit modem? -- I speak for myself, not my employer.