An on-demand secure routing protocol resilient to byzantine failures

BSMR: Byzantine-Resilient Secure Multicast Routing in Multihop Wireless Networks

“…Tree nodes with a group sequence number at least as great as that in the RREP ignore RREP messages (lines [13][14]. Otherwise, a node computes the total path weight by summing the weight of all the links on the specified path from the multicast tree to itself (lines [15][16][17][18]. If the total weight is less than any previously forwarded matching response (same requester, multicast group and response sequence number), the hop count authentication is valid and all the signatures accumulated on the response are valid, then the node appends its identifier to the end of the message, updates the hop count authentication information, signs the entire message and rebroadcasts it.…”

“…An intermediate node on the route checks if the signature on MACT is valid and if MACT contains the same sequence number as the one in the original RREQ (lines 5-7). The node then adds to its list of tree neighbors the previous node and the next node on the route as downstream and upstream neighbors, respectively, and sends MACT along the forward route (lines [15][16][17][18][19][20][21]. During the propagation of the MACT message tree neighbors use their public keys to establish pairwise shared keys, which will be used to securely exchange messages between tree neighbors.…”

“…On the other hand, if the node's WTC Timer is pending and the node notices a gap larger than ∆ in MRATE, then it simply adds its perceived rate and forwards the MRATE message (lines [10][11][12][13][14]. If MRATE contains no such large gap, the node can hope that it has been reconnected to the tree; the node cancels its WTC Timer and switches into Connected state (lines [16][17]. If the difference between the node's perceived rate and the last rate recorded in MRATE is larger than ∆, or if this difference is larger than δ and it corresponds to a single hop, then the node switches into Disconnected state, increases the weight of the link to its parent and initiates a route discovery with its updated weight list (lines [18][19][20][21][22][23][24].…”

“…Several routing protocols [10]- [13] were proposed to cope with outsider attacks or insider attacks [12], [14]- [17]. Methods proposed to address insider threats in unicast routing include monitoring [14], multi-path routing [12], [15] and acknowledgment-based feedback [16], [17]. The problem of secure multicast in wireless networks was less studied and only outside attacks were addressed [18].…”

“…SDT [15] and Ariadne [12] use multipath routing to prevent a malicious node from selectively dropping data; the disadvantage is that in a sparsely connected network, where the number of available disjoint paths is small, all of the discovered paths may contain an attacker and thus, the schemes will be less effective. ODSBR [16], [17] provides resilience to Byzantine attacks caused by individual or colluding nodes by detecting malicious links based on an acknowledgement-based feedback technique.…”