state acknowledgment packet Link State Acknowledgment Packets are OSPF packet type 5. To make the flooding of link state advertisements reliable, flooded advertisements are explicitly acknowledged. This acknowledgment is accomplished through the sending and receiving of Link State Acknowledgment packets. Multiple link state advertisements can be acknowledged in a single Link State Acknowledgment packet. Depending on the state of the sending interface and the source of the advertisements being acknowledged, a Link State Acknowledgment packet is sent either to the multicast address AllSPFRouters, to the multicast address AllDRouters, or as a unicast. See also Link-state routing protocol Flooding algorithm Computer network Open Shortest Path First References FireWire system architecture : IEEE 1394a / MindShare, Inc. ; Don Anderson Anderson, Don, 1953- Reading, Mass. : Addison-Wesley, c1999 Routing in communications networks / editor, Martha Steenstrup Englewood Cliffs, NJ : Prentice Hall, 1995 Radia Perlman “Rbridges: Transparent Routing”, Infocom 2004. Packets (information technology)