aggregate transfer rate

In your context:

Aggregate: a sum total of many heterogeneous things taken together. Heterogeneous: elements or ingredients that are not alike.

Does that clear things up?

--DF

Ah, pretty right. But considering this situation, a bus system designed to be capable of a data transfer rate up to

11.2gigabytes/second in each direction, can transfer data in both directions simultaneously, so this system has a aggregate transfer rate up to 22.4gigabytes/second. My confusion is that i can not get more information from the parameter(aggregate transfer rate) than from parameter(transfer rate). If aggregate transfer rate gives nothing, then why vendors usually emphasize this parameter? what does this parameter imply beyond transfer rate?

Ah, pretty right. But considering this situation, a bus system designed to be capable of a data transfer rate up to

11.2gigabytes/second in each direction, can transfer data in both directions simultaneously, so this system has a aggregate transfer rate up to 22.4gigabytes/second. My confusion is that i can not get more information from the parameter(aggregate transfer rate) than from parameter(transfer rate). If aggregate transfer rate gives nothing, then why vendors usually emphasize this parameter? what does this parameter imply beyond transfer rate?

Vendors emphasize the figures that will improve their sales. If a high data transfer rate figure is considered important by a vendor then he/she will do anything possible to get it as high as possible. Adding words like aggregate to the parameter may help since it permits augmenting the value by adding possibly unrelated things to it. If the resulting parameter is usefull is another thing. It may be usefull for comparison if the parameter is used by several vendors in the same way.

My car has 4 wheels plus a spare, each inflated to 2.2 bar which means that my car has an aggregate tire pressure of 11 bar! It doesn't mean anything, but what a great figure!

--DF

sounds interesting and a very nice definition of 'aggregate' thanks DF :-)

It is possible that an aggregate transfer rate could be influenced by the topology of the system, independent of the transfer rates of any individual element on the interconnect network. So the "aggregate" represents the all-out maximum using all methods and means for the given architecture.

Of course, if you've got a simple master/slave bus where only one transfer can be taking place at a given time, then the aggregate is just the transfer speed of one device. That's pretty unexciting. If bi-directional transfers are allowed, that's a little more interesting.

If the architecture allows the bus to be partitioned into non-crossing subsections and permits independent bi-directional transfers within each, that's even more interesting and a higher theoretical aggregate is possible. A fully non-blocking bi-directional single level cross-bar interconnect is, perhaps, the most desirable (but relatively expensive!) design.