  Designing protocols and formulating convenient programming units of
abstraction for sensor networks is challenging due to communication errors and
platform constraints. This paper investigates properties and implementation
reliability for a \emph{local read-write} abstraction. Local read-write is
inspired by the class of read-modify-write operations defined for shared-memory
multiprocessor architectures. The class of read-modify-write operations is
important in solving consensus and related synchronization problems for
concurrency control. Local read-write is shown to be an atomic abstraction for
synchronizing neighborhood states in sensor networks. The paper compares local
read-write to similar lightweight operations in wireless sensor networks, such
as read-all, write-all, and a transaction-based abstraction: for some
optimistic scenarios, local read-write is a more efficient neighborhood
operation. A partial implementation is described, which shows that three
outcomes characterize operation response: success, failure, and cancel. A
failure response indicates possible inconsistency for the operation result,
which is the result of a timeout event at the operation's initiator. The paper
presents experimental results on operation performance with different timeout
values and situations of no contention, with some tests also on various
neighborhood sizes.
