Distributed transaction and lock management techniques are disclosed that manage and regulate access to distributed data. A lock manager module is provided for regulating access to resources by applications in a system having a number of nodes each communicatively coupled to a network. The module can be configured to be fault tolerant. In one embodiment, the module uses a totally ordered transport that imposes total ordering protocols on messaging between nodes. The module can exploit the multicast ability of the network (e.g., Ethernet or other network features that enable multicast). The module includes a queue for each resource, the queue identifying the node that owns distributed lock for that resource. Each queue can be replicated across the nodes in a distributed configuration.