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Consider the network scenario shown in the figure on next page. FTP server S1, routers RI, R2, R3, R4 and R5 are all part of the same autonomous system (AS1) with IP address block 128.228.38.0/26. AS is multi-homed with two ISPs, ISP1 and ISP2. Router R5 is the gateway router of AS1 that is connected to the two ISPs. Router R1 is NAT enabled and is connected to the network through interface .The FTP server S1 has a private IP address 10.0.0.16. On the other side of the Internet, there is another autonomous system AS2 that contains router R6 attached with a server S2 running both DHCP and DNS. R6 also connects a wireless Access Point (AP) through Ethernet link. Client C1 is a wireless mobile device that joins the network through the AP. Note that AS2 can be reached through both ISP1 and ISP2 as well. Answer the following questions