In wireless sensor networks (WSNs)

node replication attacks and Sybil attacks can disrupt the network's operations such as data aggregation and threshold voting schemes.To launch these attacks

it is necessary to go through the neighbor discovery verification process firstly

which is not frequent in WSNs.Considering the above observations

a one-way key chain ID authentication (OKCIDA) defense mechanism was presented to decrease the probability for attackers to mount such attacks at any time.Moreover

the symmetric parameters was constructed based on the elliptic curve discrete logarithm problem;then combines with OKCIDA and utilizes node neighbor relationship

a location-free neighborhood authentication protocol (LFNA) was introduced to stop replica nodes and Sybil nodes from successfully joining into the network.Finally

the security of LFNA was proved and analyzed.Compared with several existing important mechanisms

the proposed method is superior in security and cost.