Give the steps as in Table 3.16 in the forward search algorithm as it builds the routing database for node A in the network shown in Figure 3.57.

Table 3.16)

Figure 3.57)

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Table 3.16 Steps for building routing table for node D. Step Confirmed Tentative Comments 1 (D, 0,-) Since D is the only new member of the confirmed list, look at its LSP. 2 3 5 6 7 (D, 0,-) (D, 0,-) (C, 2, C) (D, 0,-) (C, 2, C) (D, 0,-) (C, 2, C) (B, 5, C) (D, 0,-) (C, 2, C) (B, 5, C) (D, 0,-) (C, 2, C) (B, 5, C) (A, 10, C) (B, 11, B) (C, 2, C) (B, 11, B) (B, 5, C) (A, 12, C) (A, 12, C) (A, 10, C) D's LSP says we can reach B through B at cost 11, which is better than anything else on either list, so put it on Tentative list; same for C. Put lowest-cost member of Tentative (C) onto Confirmed list. Next, examine LSP of newly confirmed member (C). Cost to reach B through C is 5, so replace (B, 11, B). C's LSP tells us that we can reach A at cost 12. Move lowest-cost member of Tentative (B) to Confirmed, then look at its LSP. Since we can reach A at cost 5 through B, replace the Tentative entry. Move lowest-cost member of Tentative (A) to Confirmed, and we are all done.