First introduced in 2007, 6LoWPAN is aimed to optimize the transfer of IP protocols on top of low rate wireless protocols, mainly IEEE 802.15.4. Implementing and debugging 6LoWPAN network involves complex mixture of wireless media, IEEE MAC, the 6LoWPAN compression and fragmentation, and on top of that the IP protocol stack. 6LoWPAN has been recently adopted by the ZigBee and HomePlug alliances as part of the Smart Energy 2.0 protocol aimed for efficient Smart Grid communication. This paper describes the main issues and challenges when analyzing IP over IEEE 802.15.4 networks, and how these are addresses by the Perytons protocol analyzers and by open source tools such as the WireShark analyzer.