USB 2.0 is simply an evolution of the USB communication scheme.  It is  fully compatible with the existing 1.1 standard.  The improvement comes through increased data speeds and enhancements of the Host software and hardware managing the connection.
· More bandwidth! Up to 480 Mbps.
· Any 2.0 Hub can handle either a 1.1 or a 2.0 connection to the host.
· If a 1.1 Hub is used to connect a 2.0 peripheral to the Host the performance will be limited to the 1.1 standard.

Here are the main points of how the system will change:

· The additional roles of the Host
o The Host must now recognize the varying types of peripherals attached to it, and be able to communicate.  The speed of the host will be more than sufficient to support the higher data rates and this will pose no issues.  The true complexity will come in efficiently dividing the available bandwidth amongst the peripherals in the system.  The 2.0 system operates using the High Speed Bus states listed on the previous page.

· The additional roles of the Hub
o The Hub will now have a more intricate role in system communication.  First and foremost is must recognize what category of peripheral is attached to it and be able to support both version 1.1 and 2.0 devices simultaneously.  This will require it to monitor the speed of the data communication on both sides of the port and match them accordingly.  Additionally, it must be able to buffer higher speed communication coming from the host and store it for the amount of time necessary to pass it along to any lower speed peripherals.

· The additional roles of the Peripheral
o None!  It will be doing exactly what it would have been doing on the 1.1 standard but will be capable of doing it at the increased speed required for 2.0 operation.