The two implementation are known as Basic CAN and Full CAN.
***Note***
The terms Basic CAN and Full CAN must not be confused with the terms Standard CAN - also known as Base Frame Format (11 bit identifier, Version 2.0A data format) and Extended CAN - also known as Extended Frame Format(29 bit identifier, or Version 2.0B data format). Suitably configured, each implementation (Basic or Full CAN) can handle both Base and Extended data formats.
Basic CAN
In Basic CAN configurations there is a tight link between the CAN controller and the associated microcontroller. The microcontroller, which will have other system related functions to administer, will be interrupted to deal with every CAN message.
Full CAN
Full CAN devices contain additional hardware to provide a message "server" that automatically receives and transmits CAN messages without interrupting the associated microcontroller. Full CAN devices carry out extensive acceptance filtering on incoming messages, service simultaneous requests, and generally reduce the load on the microcontroller.
Network Sizes
The number of nodes that can exist on a single network is, theoretically, limited only by the number of available identifiers. However, the drive capabilities of currently available devices imposes greater restrictions. Depending on the device types, up to 32 or 64 nodes per network is normal, but at least one manufacturer now provides devices that will allow networks of 110 nodes.
Data Rate vs Bus Length
The rate of data transmission depends on the total overall length of the bus and the delays associated with the transceivers. For all ISO11898 compliant devices running at 1Mbit/sec speed, the maximum possible bus length is specified as 40 Metres, For longer bus lengths it is necessary to reduce the bit rate. To give some indication of this the following numbers are from the DeviceNet features list:
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