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Whenever your 48 is deployed in net mode in network address translation mode it acts as an OS I layer

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3 router as a router it does.

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Decisions decisions on where to send different packets that arrives 2 or different packets that it generates.

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Note it does so using a routing table routing table is actually a series of rules.

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Think of each rule as the next hope.

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Now the next top doesn't have to be the final destination of the packet.

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It can also be our path to another router that will run the packet forwards each routing hoping the

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routing part requires our 48 to do a routing table lookup that will pass the packet along until it reaches

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its destination no forty eight does two routing lookups for each session for the first packet that is

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sent by the originator and for the first packet that is sent by the responder as it finishes its routing

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lookups he writes the routing information in the session table and all other packets that belong to

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that session will follow this path.

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Now when your foot is tries to match a route to a packet destination it may find some routes to the

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same destination.

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Which one should he choose.

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Well it depends.

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It depends on the route attributes the road attributes determine the best road.

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All right that's enough for now.

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We will look at static crowds.

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These are roads that are entered manually.

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We will look at dynamic routing which is configured dynamically using dynamic protocols such as OS P.F..

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We will also look at policy rounds which is following its very advanced policy routing mechanism.

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We will look at the different routing attributes Internet services routing.

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So let's start.