On ADSL router, USB 1.1 and is generally maximum speed is 12Mbps, as RJ-45 100Mbps frequently. This is communication speed among PC and ADSL router. Though, Internet access speed based on speed of service provider 512Kbps, 1Mbps, 2Mbps, 4Mbps, 8Mbps, when there are many users using Internet or not. If you sign up for ADSL service package has maximum speed of 2Mbps. As remember 2Mbps than 12Mbps, so use USB or RJ-45 port speed Internet access is nothing different.