How many host names does the user's computer have to resolve? What DNS records are queried for each host name, if the host resolves both IPv4 and IPv6 addresses?

What is the minimum number of TCP connections that the user's computer has to open when loading the page, assuming that no packets are lost? Why?

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Assume that the ARP and IPv6 neighbor discovery caches are already filled, so you do not need to worry about the Link Layer in this question. Consider a user who wants to load the Web page of http://www.some-provider.org. The Web page consists of three resources: A base page hosted under www.some-provider.org/, with a size of 5KB. A stylesheet named style.css, with a size of 10KB, which is hosted on the same host as the base page. This file is referenced in the base page and contains some formatting information. An image named banner.png, with a size of 25 KB. This image is hosted on another Web server, images.some-provider.org, and is referenced in the base page. Initially, the browser cache is empty. The browser first loads the base page using unencrypted HTTP/1.1. After it has finished loading the base page, it starts loading the two other resources, first the stylesheet and then the image. Again it uses unencrypted HTTP/1.1, and the transferred content is not compressed. The size of each HTTP request is 200 Bytes. The size of all HTTP response headers is 500 Bytes in each response. The Maximum Segment Size is 1500 Bytes, the initial congestion window size is 4. The hosts are using TCP Reno and sending cumulative acknowledgements, i.e., not every segment has to be ack'ed, but just the last of multiple segments. Assume that Reno is counting segments, not bytes. No packets are being lost. The receiver window size is not a limiting factor. The IPv4 address of the computer that the user is using is 192.168.178.54, the IPv6 address is 2001: db8:8765::54. The user is using the public DNS resolver 9.9.9.9 over UDP over IPv4. The computer resolves each host name to both IPv4 and IPv6 addresses. It loads the actual Web page over IPv6. You can freely assign global IP addresses to the Web servers involved. The server running at images.some-provider.org is a different Web server than www.some-provider.org, a and both host names resolve to different IP addresses. Assume that the ARP and IPv6 neighbor discovery caches are already filled, so you do not need to worry about the Link Layer in this question. Consider a user who wants to load the Web page of http://www.some-provider.org. The Web page consists of three resources: A base page hosted under www.some-provider.org/, with a size of 5KB. A stylesheet named style.css, with a size of 10KB, which is hosted on the same host as the base page. This file is referenced in the base page and contains some formatting information. An image named banner.png, with a size of 25 KB. This image is hosted on another Web server, images.some-provider.org, and is referenced in the base page. Initially, the browser cache is empty. The browser first loads the base page using unencrypted HTTP/1.1. After it has finished loading the base page, it starts loading the two other resources, first the stylesheet and then the image. Again it uses unencrypted HTTP/1.1, and the transferred content is not compressed. The size of each HTTP request is 200 Bytes. The size of all HTTP response headers is 500 Bytes in each response. The Maximum Segment Size is 1500 Bytes, the initial congestion window size is 4. The hosts are using TCP Reno and sending cumulative acknowledgements, i.e., not every segment has to be ack'ed, but just the last of multiple segments. Assume that Reno is counting segments, not bytes. No packets are being lost. The receiver window size is not a limiting factor. The IPv4 address of the computer that the user is using is 192.168.178.54, the IPv6 address is 2001: db8:8765::54. The user is using the public DNS resolver 9.9.9.9 over UDP over IPv4. The computer resolves each host name to both IPv4 and IPv6 addresses. It loads the actual Web page over IPv6. You can freely assign global IP addresses to the Web servers involved. The server running at images.some-provider.org is a different Web server than www.some-provider.org, a and both host names resolve to different IP addresses.