3. [6 points] In the routing protocols, each node needs to exchange messages with other nodes in order to build its forwarding table. List the difference between Distance Vector Routing Protocol (DV) and Link State Routing Protocol (LS) in terms of what information is sent by each node and which nodes the information is sent to. We assume the costs of all links remain constant. 4. [6 points Consider the following network fragment: v has three attached neighbors, u, w, and x. u is connected only to v. w has a minimum-cost path to destination yof7, and x has a minimum-cost path to y of 6. The complete paths from w and x to y are not shown. All link costs in the network have strictly positive integer values