Re: [paho-dev] MQTT-SN talk at EclipseCon

[Ian Craggs <icraggs@xxxxxxxxxxxxxxxxxxxxxxx>]

Stefano,

MQTT-SN has features which take advantage of the underlying transport's 
ability to support multicast or broadcast, like that in UDP for 
instance.  This means that gateways (or servers) can advertise their 
presence, and then clients can dynamically connect to them, switching 
from one gateway to another as needed.

Every client can also multicast or broadcast messages.  This means that 
messages can be sent to a gateway or another client without a connection 
having to be established.  Each client could also relay messages that it 
receives, or filter out those that it is not interested in.

So in MQTT-SN, you can use a connection to a server, similar to MQTT, or 
you can use multicast to send messages to every other participant in the 
group.

Ian



On 03/16/2015 02:09 PM, Stefano Costa wrote:
> Il 16/03/2015 12:54, Ian Craggs ha scritto:
> > https://www.eclipsecon.org/na2015/session/mqtt-sn-mqtt-udp-zigbee-and-other-transports 
>
> Ian,
> the slides are really well prepared and useful for a concise 
> understanding of the why/when for MQTT and MQTT-SN.
>
> I was particularly impressed by a statement you make in the web page:
>
> "MQTT-SN also allows mesh networking"
>
> Can you briefly elaborate this? I didn't carefully study MQTT-SN yet 
> but I don't think this has the common meaning of a "mesh networking" 
> like Zigbee and similar, or am I wrong? Would be very interesting!

--
Ian Craggs
icraggs@xxxxxxxxxx                 IBM United Kingdom
Paho Project Lead; Committer on Mosquitto