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TitleMesh Networks
TagsRouter (Computing) Computer Network Network Architecture Media Technology Areas Of Computer Science
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Page 1

www.digi.com

Wireless Mesh Networking
ZigBee® vs. DigiMesh™

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Abstract
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Page 2

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2

ZigBee Nodes

The ZigBee Protocol defines three types of nodes: Coordinators, Routers and End Device, with a requirement
of one Coordinator per network. While all nodes can send and receive data, there are differences in the
specific roles they play.

��� ����#� ! are the most capable of the three node types. There is exactly one coordinator in each network
and it is the device that establishes the network originally. It is able to store information about the network,
including security keys.

�$#� ! act as intermediate nodes, relaying data from other devices.

��� ��%�
�! can be low-power / battery-powered devices. They have sufficient functionality to talk to their
parents (either the coordinator or a router) and cannot relay data from other devices. This reduced
functionality allows for the potential to reduce their cost.

ZigBee offers these advantages:
• Open standard with interoperability between vendors
• Option for lower cost, reduced function end nodes

C Coordinator
C

E End Device

E
E

E

E

E

E

R Router R

R
R

R

R
R

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DigiMesh Nodes

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Sleeping Routers

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Additional Differences

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Digi Mesh Nodes

DN
DN

DN
DN

DN DN

DN
DN

DN

DN

DN
DN

DN

DN

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Comparison Table

4

�" ��1 ��*! �" "��*!

�&�� �/’�*� �%��"+*
Coordinators, Routers, End Devices. End
Devices potentially less expensive because
of reduced functionality.

One type, homogenous. More flexibility to
expand the network. Simplifies network
setup. Increases reliability in environments
where routers may come and go due to
interference or damage.

�#��’"% �&,+�)*�

�++�)/ �"��

Only End Devices can sleep. All nodes can sleep.No single point of
failure associated with relying on gateway
or coordinator to maintain time
synchronization.

�-�)�+!���") �")$.�)� �’��+�* Yes Not currently scheduled.

�&% ��% � �’+"&%* Most ZigBee devices have range of less
than 2 miles (3.2 km) for each hop.

Available on XTend™, with range of up to
40 miles (64 km) for each hop.

�)�$� ��/#&��� �!)&, !’,+ Up to 80 bytes. Up to 256 bytes, depending on product.
Improves throughput for applications that
send larger blocks of data.


&�� �"0� Larger. Less room for growth in features. Smaller (about half ZigBee PRO). More
room for growth in features.

�,’’&)+�� �)�(,�%�"�* �%�

�� ��+� ��+�*

Predominantly 2.4 GHz (250 kbps). 900
MHz (40 Kbps) and 868 MHz (20 Kbps) not
widely available.

900 MHz (10, 125, 150 Kbps).
2.4 GHz (250 Kbps)*.

���,)"+/ AES encryption. Can lock down network
and prevent other nodes from joining.

AES encryption.**

�%+�)&’�)��"#"+/ Potential for interoperability between
vendors.

Proprietary

�%+�)��)�%�� �&#�)�%�� Direct-Sequence Spread Spectrum (DSSS). 900 MHz: Frequency-Hopping Spread
Spectrum (FHSS).
2.4GHz: Direct-Sequence Spread Spectrum
(DSSS).

���)�**"% Two layers. MAC address (64 bit) and
Network address (16 bit).

MAC address (64 bit) only.

��"%+�%�%�� More sniffers and diagnostic tools available
on market.

Simpler addressing can help in diagnosing
problems and setting up a network.

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�0 �&$"% *&&%
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