Arris DG3270 supports speeds up to 2 Gbps. Arris DG3270 has 3 different speed tiers: DOCSIS 3.1, DOCSIS 3.0 and DOCSIS 2.0. There is a difference between speeds and tiers: you can buy a modem speed tier, or a speed tier can be upgraded to another speed tier. In other words, if you buy the standard DOCSIS 3.1 tier, for example, your cable modem will theoretically be able to support data speeds of up to 2 Gbps. If you're interested in upgrading from that speed tier and getting a DOCSIS 3.0 or 2.0-speed tier, your cable modem will theoretically be able to support data speeds of up to 1 Gbps.