Atmel AVR2070 - Manual (Page 2)

2
AVR2070
8240B-AVR-06/09
2 Stack Architecture
Route Under Mac (RUM) is a small 802.15.4 protocol developed by Atmel. This
protocol routes packets at the MAC layer, as opposed to the application or IPv6 layer,
which would be a route over scheme. The under comes from the fact that routing is
done at a low level. This has a number of advantages:
• Routers and end nodes can be simpler, and therefore less expensive. These
nodes manage almost no routing information.
• The coordinator knows all pertinent information about every node in its PAN,
which means special “guessing” routing algorithms are not needed.
• Higher level code does not have to be concerned with routing, and has only
to send a packet to a destination address.
The main components of the stack include RUM, and IPv6 / 6LoWPAN. The complete
stack features the following highlights:
• Small object size. A minimal build, with only RUM and a tiny example
application, is about 6KB for an AVR end node.
• Self-forming network. Nodes power up, find a network, and associate to it.
• Self-healing network. Nodes re-associate upon a failure to communicate.
• Multi-hop routing. Nodes can be multiple hops away from the coordinator.
• Source Code Included. Free for use and free to modify if used with Atmel
hardware.
• Designed to be a base platform for customer applications.
• Very configurable, with the ability to add or remove features at compile time.
Features include 6LoWPAN frames, end node sleeping, and a terminal mode.
• Portable to almost any Atmel processor.
Figure 2-1 RUM Architecture