Path recovery mechanism in 6LoWPAN routing

Abstract

The feature of 6LoWPAN is the capability of the dynamic assignment of 16-bit short addresses. Hierarchical routing (HiLow) algorithm that uses dynamically assigned 16-bit unique short address as its interface identifier has an advantage of memory saving. The 16-bit unique short address is assigned to a 6LoWPAN device during an association operation with a neighbor node which is also called parent node in HiLow. Besides reducing the overhead of maintaining routing table, HiLow also supports for larger scalability. However, previous research did not deal with the path recovery when sensor nodes in HiLow are failed. The node failure may be due to the battery lifetime of the 6LoWPAN device. This kind of failure will cause the expiration of the association event and make the previously assigned 16-bit short address of the child node from the failure parent node become invalid within PAN. In this paper, a new path recovery mechanism so-called step parent node (SPN) algorithm is proposed to conventional HiLow to reassign the valid 16-bit short addresses for the child nodes of the failure parent node and provide the path robustness. The child nodes of the failure parent node will broadcast a step parent node request message (spn_request) to the neighbor nodes. The neighbor node whose child nodes do not exceed the maximum child value will act as a step parent node of the new child nodes. It enhances the reliability of conventional hierarchical routing mechanism.

Architecture and Routing Protocols for Smart Wireless Home Sensor Networks

“…erefore, when any node or link is removed or failed, the network is no longer connected and a fast network maintenance schema responding to node mobilities and failures is imperative to build stable and well-performance wireless home sensor network. Although there have been some path recovery mechanisms used in WSN [13,14], they may be inefficient and costly according to WHSN architecture and routing protocols. In this section, we introduce mobile node maintenance and path recovery algorithm based on our WHSN architecture.…”

“…(1) for each node in WHSN do (2) if (node ⋅ feature = plug-in) then (3) node ⋅ state ← head; (4) broadcast(Head_Msg); (5) Join_Msgs ←receiveJoinMsgs(); (6) for Join_Msg ∈ Joiln_Msgs do (7) node ⋅ clusterMb ⋅ add(Join_Msg ⋅ sender); (8) end for (9) else (10) node ⋅ state ← plain; (11) Head_Msgs ←receiveHeadMsgs(); (12) if Head_Msgs ≥ ∅&& state = plain then (13) sender ← Head_Msgs(0) ⋅ sender(); (14) node At �rst, each plug-in node broadcasts massages to clarify its desire to be cluster header (line 3). en, it waits for others to �oin its cluster.…”

“…REQs ← receiveREQs(); (5) if REQs ≠ ∅ then (6) node ⋅ send(REQs ⋅ getSend(), DATA); (7) else (8) node ⋅ broadcast(ADV); (9) REQs ← receiveREQs(); (10) if REQs ≠ ∅ then (11) node ⋅ send(REQs ⋅ getSend(), DATA); (12) end if (13) end if (14) has data to share (line 2), it broadcasts an ADV request message to clarify its desire (line 3). When it receives REQ responses from neighbors (line 4), the packet routing request could be satis�ed by these neighbors, and the packet is sent to them (line 6).…”

“…send( , packet); (8) else (9) discard(packet); (10) end if (11) end for (12) else ifComp = 0 then (13) hold ( …”