AVR-Chat

According to Maxtream their XBee modules are not true mesh, they have some
beta mesh software that implements routers that aren't the coordinator as
the mesh spec says, but it is beta.  The shipping code does not support
true mesh networking...Yet.

DLC

> re below...
> ZigBee 1.0 is a mesh by my definition: Nodes are configured with a
> network name. At power-up, every node seeks out its neighbors. A
> message from node A to node X may be relayed by zero or more nodes,
> mesh-like.  ZigBee defines a "coordinator" node. This node manages
> network address assignments (kind of like ARP and DHCP in ethernet).
> Maxstream even has a DNS-like node-name capability (beyond ZigBee).
>
> I've used  the XBee's and other vendors' with ZigBee mesh-like - with
> 4 hops. I've shut down intermediate nodes and seen the mesh reform on
> the fly to reroute.  One hop = 80K bytes/sec by my measures with an
> ideal signal to noise and no interference.
>
> Most vendors today are limiting the max discovered neighbors to about
> 5, due to memory limitations.
>
> A star topology, per me, means there is no routing at all and the hop
> count is 1 for every message. The route from a node to the coordinator
>  or gateway can be several hops. Often, the coordinator is a bridge to
> a PC and thus a kind of gateway, if the PC forwards traffic to a WAN.
>
> The semantics are not well defined.
>
>
> --- In AVR-Chat@yahoogroups.com, dlc@... wrote:
>>
>> Now I'm confused.  The manual specifically addresses sleep mode and
>> indirect messaging in a non-beacon network.  Is that then a custom XBee
>> protocol that isn't Zigbee?
>>
>> In my conversations with Maxstream they don't even have mesh networking,
>> only star networking since their Zigbee does not yet have mesh.
>>
>> ???
>> Now I'll have to go back to them and talk about it all over again.
> Also,
>> if you are going to use "Zigbee" in your product literature and you
> have a
>> Zigbee compliant (and tested) module like the XBee units then you only
>> need to have the $1500 membership and ONLY on the year that you release
>> the product to the public.  You only need to be listed in the Zigbee
>> alliance (apparently) not a full voting member.  That is how I
> understand
>> it from when I took classes on Zigbee, but that was last year, this year
>> may be different...
>>
>> DLC
>>
>> > I had a chat with MaxStream about the XBee modules (they were very
>> > helpful). To clarify the question of sleep mode:
>> >
>> > Me: I was looking at the XBee/Pro manual and it seems the Zigbee
> modules
>> > don't support sleep mode?
>> > MS: That is correct. The XBee's do not yet support a sleep mode when
>> > using the ZigBee firmware. If you are using the 802.15.4 firmware with
>> > the XBee's, sleep mode is supported in that case.
>> > Me: Would I be right in saying that if I want mesh networking (i.e.
>> > Zigbee rather than 15.4) and battery powered sensor nodes, then
> XBee is
>> > not suitable?
>> > MS: Not yet, that's correct. We expect to have a solution that will
>> > provide mesh networking with sleep mode for end nodes (for your
> battery
>> > powered sensor nodes in that case) very soon (in the next 30 - 60
> days).
>> >
>> > I also asked MaxStream and Zigbee Alliance about licensing and
>> > membership fees. The ZA response:
>> >
>> > "If you are going to use ZigBee specification building
>> > commercial sensor modules around MaxStream's XBee modules then we
> answer
>> > is "yes" you have to be a member of the ZigBee.
>> >
>> > You can then develop a ZigBee product with no additional license fees
>> > imposed by the ZigBee Alliance unless you want to market your product
>> > under the ZigBee name. With other words, if you don't call you
> product a
>> > ZigBee device, you do not have to undergo any other certification and
>> > licensing. However, we recommend that you go through a no-harm test
>> > program to ensure that other networks will not harm you and
> vice-versa."
>> >
>> > MaxStream's final word on the subject:
>> >
>> > "You asked if there was any licensing fee for use of the ZigBee XBee
>> > modules. There is only a licensing fee to the ZigBee Alliance if
> you use
>> > the word "ZigBee" in your marketing of your product. For more
>> > information about that, you will have to contact the ZigBee Alliance."
>> >
>> >
>> > I'm not sure whether or not it's necessary to use the Zigbee
>> > specification to build a Zigbee sensor network around XBee modules
> - if
>> > it is then I in principle have to pay $3500 for use of the spec.
>> >
>> > Mark
>> >
>> >
>> >
>> > stevech11 wrote:
>> >> Remember, use of the ZigBee network layer is optional in all these
>> >> 802.15.4 modules. Without ZigBee it's like using Ethernet without
> IP -
>> >> you can address packets by the MAC address.
>> >>
>> >> The current (about to change) ZigBee standard says that end-nodes
>> >> (network leaf) can sleep. Routers cannot sleep. This is a big issue
>> >> for the new standard.
>> >>
>> >> --- In AVR-Chat@yahoogroups.com, dlc@ wrote:
>> >>
>> >>>   I don't think that you read the manual correctly.  Unless you want
>> >>>
>> >> some
>> >>
>> >>> other kind of sleep mode.  To quote from the "Sleep" section of the
>> >>> XBee
>> >>> manual:
>> >>>
>> >>> "Sleep Modes enable the RF module to enter states of low-power
>> >>>
>> >>
>> >
>> >
>> >
>> > Yahoo! Groups Links
>> >
>> >
>> >
>> >
>>
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