Okay, so now where was I…ahhh yes, how the network data request processes the addresses. Inside the network layer on the transmit side, you only have one piece of real information which is the destination address. From that you'll have to figure out the next hop address for the MAC. You can say that most of the network layer exists just to figure out what the next hop address will be. To figure out the next hop, you have to go through a series of comparisons. Although the order is dependent on the stack, I'll refer to the order that I use. The first comparison is to see if the destination is a broadcast. Zigbee has a few classes of broadcasts: broadcast to everyone, broadcast to routers, and broadcast to non-sleeping nodes. Upon checking the spec again, I see that there is a broadcast for low power routers as well, although I' haven't seen this used in the spec. I'll go into broadcasting in more detail later, but suffice it to say that if the destination address falls into the broadcast category, then the next hop address is simple…it will be the 802.15.4
Okay, so now where was I…ahhh yes, how the network data request processes the addresses. Inside the network layer on the transmit side, you only have one piece of real information which is the destination address. From that you'll have to figure out the next hop address for the MAC. You can say that most of the network layer exists just to figure out what the next hop address will be. To figure out the next hop, you have to go through a series of comparisons. Although the order is dependent on the stack, I'll refer to the order that I use. The first comparison is to see if the destination is a broadcast. Zigbee has a few classes of broadcasts: broadcast to everyone, broadcast to routers, and broadcast to non-sleeping nodes. Upon checking the spec again, I see that there is a broadcast for low power routers as well, although I' haven't seen this used in the spec. I'll go into broadcasting in more detail later, but suffice it to say that if the destination address falls into the broadcast category, then the next hop address is simple…it will be the 802.15.4