Home/Support/Support Forum/Source routing - Memory limitation to store source routes

Source routing - Memory limitation to store source routes

0 votes
Hi,

I need to do a source routing transmission in a network that contains 1 coordinator and 50 Routers. To do that I need to store in memory 50 source routes containing an undefined number of routes (hops).

I need to allocate space memory but I do not know the space that I will need because the routes are undefined. If I limit the maximum hops to 4, the source routes will have a maximum number of hops to 4?

Lets say I want to transmit from router R1 to router R7:

R1-> R2 -> R3 -> R4- -> R5 - > R6 -> R7

The question is, If I limit the hops to 4 what will happen is: (considering that R5 is in range of R7)

R1 -> R2 -> R3 -> R4 -> R5 -> R7

??
asked Dec 4, 2015 in IEEE 802.15.4 by Rgoncalves New to the Community (1 point)

Please log in or register to answer this question.

1 Answer

0 votes
No, if you use the S2C modules you do not need to use source routing as the routing table is larger. Even then you do not need to use source routing. Source routing is only recommend to decrease the amount of rout discoveries are performed. Now if you just send broadcast packet from the Coordinator, again you do not need to use source routing as you are not updating a table.
answered Dec 4, 2015 by mvut Veteran of the Digi Community (11,302 points)
Thanks for the reply.

I am using as a coordinator XBEE PRO S2B XBP24BZ7WIT-004J and as routers XB24-Z7UIT-004.

I cannot send broadcast since it delays enormously  the transmissions and hangs de network. I am sending 50 transmissions with a delay of 10ms between them and what I have discover in practice is that for 50 routers sourcing routing works good but the number of hops is undetermined. So the question was, if I limit the number of hops, can I have source route limit to the number of hops?

Other thing:

Was it because I had BH (Broadcast radius) set to 0, that broadcast messages hangs my network?

What if I use broadcast messages with number of hops set to 2 or 3, will this solve my brodcast hang problem?

Thanks
You are trying to send too much data for a Mesh network.  You can't send data every 10ms.  A Zigbee Mesh or any mesh simply can't handle that much traffic.

For a network of 50 nodes, you don't need to use source routing.  Simply because that is the max number of entries that module supports.
Let me correct that. I am sending 3 Bytes for 50 nodes with 10ms delay between every  30 seconds. The network can handle because I have seen it work but obviously in practice it wont transmit every 10ms, no problem, as long the data gets there.  .

Other thing:

Was it because I had BH (Broadcast radius) set to 0, that broadcast messages hangs my network?

What if I use broadcast messages with number of hops set to 2 or 3, will this solve my broadcast hang problem?
...