Characteristics of LoWPAN's

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Characteristics of LoWPAN's are as follows:


1.Small packet size: Maximum physical layer packet size=127 bytes.
                                Maximum frame size at the media aceess control layer=102 octets
                               Link-layer security imposes further overhead,which in the maximum case has 
                                 21 octets as overhead leaving 81 octets for data packets.

 2. Support for both 16-bit short or IEEE 64-bit extended media access control addresses.

 3.Low Data rates:  Data rates --->Physical Layer
                              250kbps  ---->2.4GHz
                              40kbps    ----> 915MHz
                              20kbps   ----->868MHz

 4.Topologies : Mesh,Star.

 5. Low Power: As most of the devices are battery operated.

 6.Low Cost:    As devices are typically associated with sensors,switches etc..so it requires less      
                         processing,low memory which in turn is nothing but lower cost.

 7.Location:  Location is typically not predefined. Sometimes, the location of these devices not be easily 
                      accessible. sometimes , they may move to a new location

 8.Devices sometimes may be unreliable due to uncertain radio connectivity,battery drain,etc

 9.Mostly the devices will be in sleep for long periods of time in order to conserve energy..and during this time they are unable to communicate with other devices.

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