Link State algorithms....Global Routing

In Link State algorithms every router has to follow these steps:

1-Identify the routers that are physically connected to them and get their IP addresses:

When a router starts working, first send a "HELLO" packet over network. All the routers that receive this packet, reply  with a message that contains their IP addresses.

2-measure the delay time (or any important parameters of network such as average traffic) for neighbor routers:

IIn order to do that routers send Echo packets over the network, every router that receives these packets replies with an Echo reply packet By dividing Round Trip Time by 2, routers can count the delay time. (Round Trip Time is a measure of the current delay on a network, found by timing a packet bounced off some remote host). Note that this time  includes both transmission and processing times. (The time in which t packets reach the destination and the time in which the receiver processes it and replies.)

3-broadcast its information over a network for other routers and receive theirs:

In this step, all routers share their knowledge and broadcast their information to each other. In this way, every router can know the structure and status of network.