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So what are some of the benefits or advantages of link-state routing protocols?

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Well firstly, faster convergence, changes are reported immediately

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and links state routing protocols tend to converge a lot quicker

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than distance vector routing protocol such as RIP.

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now that said EIGRP which is an enhanced distance vector routing protocol

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does also converge very quickly, it has the simplicity of configuration

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of a distance vector routing protocol

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but does have many of the advantages of a link state routing protocol

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link state routing protocols are also more robust as the routers

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know the full topology of the network or area

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they thus tend to be less susceptible to routing loops

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because of their great visibility of the network.

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Routers know the topology and can does work out the best route to every destination.

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Link state packets are also sequence and acknowledged within OSPF.

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So if an update I not received by a router

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it will be retransmitted

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RIP doesn’t form neighbor relationship or peer relationships but OSPF does.

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So if 1 router sends an update to a peer

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and that peer doesn’t acknowledge receipt of the routing update

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the router will retransmit the update.

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The hierarchical design of OSPF

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and other link state routing protocols optimizes resources.

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It allows for smaller routing tables

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because of address summarization and fewer Shortest Path First calculation

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because of address hiding, essentially if the network is designed properly

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some routers will have very small routing tables

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compared to others and will do foul fewer calculations.

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Routers in area 1, for example, will not be aware

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of all the routes in area 2 or area 3

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because of the use of summarization on the Area Border Routers

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and the configuration of special areas such as stub areas.

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The hierarchical design also allows link state routing protocols to scale

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and thus work in much larger environments than distances routing protocols could.

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Large ISPs in the Internet, for example, may run OSPF or ISIS internally

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within the autonomous systems, OSPF and IS-IS are preferred

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to routing protocols such as RIP because they are a lot more scalable.