In which state are DR and BDR elected in an OSPF broadcast network?

In an OSPF (Open Shortest Path First) broadcast network, the election of the Designated Router (DR) and Backup Designated Router (BDR) occurs in the 2-way state. During this state, OSPF routers exchange hello packets and establish neighbor relationships.

After the initial exchange of hello packets, routers build a list of their neighbors and determine who will act as the DR and BDR. The router with the highest priority becomes the DR, and the second-highest priority becomes the BDR. This election process is essential to minimize the amount of routing information exchanged in a broadcast environment, thereby optimizing the network's performance.

The other states mentioned, such as the Init state, Attempt state, and Exchange state, do not relate to the actual election of the DR and BDR. The Init state denotes that a router has seen hello packets from a neighbor but has not yet formed a bidirectional relationship. The Attempt state is specific to non-broadcast multi-access (NBMA) networks and is not relevant for broadcast networks, where the DR and BDR elections occur. The Exchange state is where routers begin exchanging detailed routing information, but it occurs after the 2-way state and does not involve the election process for