A virtual synchrony wide area network (100) which has at least a first
local area network (LAN) (110) and a second LAN (120). A first router
(114) and a second router (116) are connected to the first LAN (110), and
a third router (142) and a fourth router (146) are connected to the
second LAN (120). A point-to-point link (152) is connected between the
first and third routers, (154) between the first and fourth routers,
(156) between the second and third routers, and (158) between the second
and fourth routers. Each router is provided with computer program code
(206) for controlling the flow of messages through the routers and to
maintain local total order with minimal latency.