A method and apparatus is disclosed which enables detection of undesired packets received at a device in a network, where the device is a member of a group of devices in the network. A registration table stores transform identifiers for each member of a group and controls the forwarding of the transform identifiers to the members of the group as members are added and deleted. A transform identifier indicates a format or transformation of a packet transmitted by an associated member. The transform identifier can therefore be used at a receiving device to distinguish between transmissions by different members of the group, thereby enabling the receiving device to extract sequence information associated with the member from the packet. The sequence information can be compared against an expected sequence number for the member to determine whether the packet is an undesirable or rogue packet.