3. (20 points) Assume you are in a private network connected to the Internet via a router. Your node's IP address is 192.168.45.121/28 Net ID in decimal? Range of valid IPs? to Which IP address is used for the router interface? The router has another interface connected to the Internet. That public IP address is 144.37.12.45 Node1 (192.168.45.121 port 3003) sends an HTTP request to Google server whose IP address is 54.23.130.30 (port 80), and Google server replies. Node2 (192.168.45.125 port 3003) sends an SMTP request to Amazon mail server whose IP address is 145.23.170.92 (port 25), and Amazon mail server replies. Create port numbers at router starting from 6200 Fill in the blanks in the picture below. Enter the IP addresses and ports for packets' sources and destinations at each step and also in NAT table. Enter the IP addresses asked in the picture (22 blanks) NAT translation table WAN side addresses LAN side addresses Public IP, Public Port Private IP, Private Port S1 (IP, port): D1 (IP, port) S1 (IP, port): D1 (IP, port) Node1 Google S1 (IP, port): D1 (IP, port) LAN'S S1 (P, port): 3routerD1 (IP, port): 4 IP: Switch Amazon S1 (IP, port) D1 (IP, port): S1 (IP, port): D1 (IP, port): Node2 S1 (IP port): D1 (IP, port): S1 (IP, port): D1 (IP, port) 4 4. (20 points) Using the configuration of last question, now assume packets pass two routers to reach destination. The picture below contains your private network, the servers, and the routers in between. Nodel sends a message to Google server. (Pay attention: who is the source, who is the destination?). A frame is created at nodel to send the packet to the router. Then the frame is processed and updated in each router to forward the packet to the next hop. Node2 also sends a message to Amazon mail server. Fill in the blanks in the picture Specify the source and destination IP addresses and MAC addresses for frames and their enclosed IP packets (48 items need to be filled). Assume the ARP tables contain all the required mappings The MAC addresses in this network are given in underlined numbers at each interface. For example 11...1 (meaning 11-11-11-11-11-11) is the MAC address of nodel. You can use the same notation in your answer IP addresses of left router's interfaces are given in the table below. Note that you may or may not need these IP addresses. The other IP addresses (like Google) are the same as the ones given in the last question MAC address IP address 55...5 66...6 56.84.62.79 54.23.130.1 145.23.170.1 S1 IP: D1 IP: S1 MAC: D1 MAC S1 IP: D1 IP S1 MAC D1 MAC S1 IP: D1 IP S1 MAC D1 MAC 3 2 S1 IP: D1 IP: S1 MAC: S1 IP: D1 IP: S1 MAC: D1 MAC S1 IP D1 IP S1 MAC D1 MAC: 4 6 Node1 Google D1 MAC 88..8 66...6 55...5 44...4 Switch 33...3 LAN's router 99...9 Amazon S2 IP S2 IP: S2 IP D2 IP: 2 1 D2 IP: Node2 3S2 MAC S2 MAC S2 MAC: D2 MAC: D2 MAC: D2 MAC S2 IP: D2 IP: S2 MAC D2 MAC S2 IP: D2 IP: S2 MAC D2 MAC S2 IP: D2 IP: S2 MAC: D2 MAC 4 5 3. (20 points) Assume you are in a private network connected to the Internet via a router. Your node's IP address is 192.168.45.121/28 Net ID in decimal? Range of valid IPs? to Which IP address is used for the router interface? The router has another interface connected to the Internet. That public IP address is 144.37.12.45 Node1 (192.168.45.121 port 3003) sends an HTTP request to Google server whose IP address is 54.23.130.30 (port 80), and Google server replies. Node2 (192.168.45.125 port 3003) sends an SMTP request to Amazon mail server whose IP address is 145.23.170.92 (port 25), and Amazon mail server replies. Create port numbers at router starting from 6200 Fill in the blanks in the picture below. Enter the IP addresses and ports for packets' sources and destinations at each step and also in NAT table. Enter the IP addresses asked in the picture (22 blanks) NAT translation table WAN side addresses LAN side addresses Public IP, Public Port Private IP, Private Port S1 (IP, port): D1 (IP, port) S1 (IP, port): D1 (IP, port) Node1 Google S1 (IP, port): D1 (IP, port) LAN'S S1 (P, port): 3routerD1 (IP, port): 4 IP: Switch Amazon S1 (IP, port) D1 (IP, port): S1 (IP, port): D1 (IP, port): Node2 S1 (IP port): D1 (IP, port): S1 (IP, port): D1 (IP, port) 4 4. (20 points) Using the configuration of last question, now assume packets pass two routers to reach destination. The picture below contains your private network, the servers, and the routers in between. Nodel sends a message to Google server. (Pay attention: who is the source, who is the destination?). A frame is created at nodel to send the packet to the router. Then the frame is processed and updated in each router to forward the packet to the next hop. Node2 also sends a message to Amazon mail server. Fill in the blanks in the picture Specify the source and destination IP addresses and MAC addresses for frames and their enclosed IP packets (48 items need to be filled). Assume the ARP tables contain all the required mappings The MAC addresses in this network are given in underlined numbers at each interface. For example 11...1 (meaning 11-11-11-11-11-11) is the MAC address of nodel. You can use the same notation in your answer IP addresses of left router's interfaces are given in the table below. Note that you may or may not need these IP addresses. The other IP addresses (like Google) are the same as the ones given in the last question MAC address IP address 55...5 66...6 56.84.62.79 54.23.130.1 145.23.170.1 S1 IP: D1 IP: S1 MAC: D1 MAC S1 IP: D1 IP S1 MAC D1 MAC S1 IP: D1 IP S1 MAC D1 MAC 3 2 S1 IP: D1 IP: S1 MAC: S1 IP: D1 IP: S1 MAC: D1 MAC S1 IP D1 IP S1 MAC D1 MAC: 4 6 Node1 Google D1 MAC 88..8 66...6 55...5 44...4 Switch 33...3 LAN's router 99...9 Amazon S2 IP S2 IP: S2 IP D2 IP: 2 1 D2 IP: Node2 3S2 MAC S2 MAC S2 MAC: D2 MAC: D2 MAC: D2 MAC S2 IP: D2 IP: S2 MAC D2 MAC S2 IP: D2 IP: S2 MAC D2 MAC S2 IP: D2 IP: S2 MAC: D2 MAC 4 5