Any packet (message) entering the MORSE network can be labelled as a
broadcast one. Either the user labels selected packets, or it is possible
to set labelling of all packets coming through the user part of the
respective CNI (Channel to Node Interface). Once a broadcast packet enters
the network, it is spread around following
(B)c menu settings
of all the nodes that receive it.
With careful settings in all network nodes it is possible to achieve the ultimate goal of broadcasting – to deliver a message simultaneously to all network members – even in large networks with a complex architecture.
When a broadcast packet is transmitted in the RF channel, every
receiving CU delivers it to the respective node (to all 5 nodes in radio
part). There it is checked for the source address first. If the source
address corresponds with the node settings (src base & mask), the
packet is multiplied and delivered simultaneously to different node
outputs according to the
(B)c menu settings.
For example, let us have the user and net node outputs switched on. The received (and checked) broadcast packet is then delivered to the user channel and simultaneously to the retranslation network channel. The latter is typically the RF channel, so in this example the packet will be transmitted on the RF channel again. Using the configuration described above, even broadcast packets can exploit store-and-forward repeaters. Of course an effective algorithm for discarding repetitive packets is implemented.
From MORSE Main menu type B e Enter Enter .
Multicast routing (Broadcasts): Nid|src base mask u|l n N a (0) 00000000 FFFFFFFF | - 00000000 (1) 690F0010 FFFFFFF0 u| n - 690F0003 (2) 00000000 FFFFFFFF | - 00000000 (3) 00000000 FFFFFFFF | - 00000000 (4) 00000000 FFFFFFFF | - 00000000
type 1 Enter
Multicast routing (Broadcasts): (s)ource base addr:690F0010 (m)ask:FFFFFFF0 (u)ser output:ON (l)ink output:OFF (n)et output:ON (N)ode ID:255 next (a)dr:690F0003
|(s)ource base addr: 690F0010|
— Base address compared to the source address of the received packet
— Only masked parts of the
|(u)ser output: ON|
— Switch for sending a packet copy to the user output of the node
|(l)ink output: OFF|
— Switch for sending a packet copy to the retranslation link output of the node
|(n)et output: ON|
— Switch for sending a packet copy to the retranslation net output of the node
|(N)ode ID: 255|
— Switch for sending a packet copy to the next node within the same CU (No.0 to No.4, whilst 255 means no next node).
|next (a)dr: 690F0003|
— When a broadcast packet is sent to the retranslation net
output, this address denotes the node from which the acknowledgement
will be expected (this is used for secured transfer of a broadcast
packet between repeaters on an RF channel).