Answer Happy

(d) A mixture of IPv4 and IPv6 networks are normally used by mobile and fixed network providers, with typically IPv4 at the backbone (core) and IPv6 at the edges. Figure 1.3 below, shows four IPv6 subnets, connected by a mix of IPv6-only routers (shaded blue), IPv4-only routers (shaded red) and dual- capable IPv6/IPv4 routers (shaded blue with red interfaces to IPv4 routers). Suppose that a host of subnet D wants to send an IPv6 datagram to a host on subnet B. Assume that the forwarding between these two hosts goes along the path: D --> E--> d --> b --> c --> B: (i) Which protocol encapsulates the other: IPv4 or IPv6? (ii) For the IP packets from E to d, what is the IP source and destination addresses. What is the source and destination of the encapsulated IP packet. (iii) For the packets om c to B, what is the IP source and ination addresses. What is the source and destination of the encapsulated IP packet A4RE:BEC2:E753:BA44:3E92:44C:ED59:F14F 93E77421:BA77:C998:19EA: 106:0948 IPv6 222.49.60.3 220.10.37.32 C subnet F a b F F30642C50EF3:8192C171 996F:6937:A57F:695F:29E7:7C37:E94F:6835 A D IPv6/v4 IPv4 IPv6/v4 IPv6 subnet A IPv6 subnet D IPv6 C E IPv6 IPv4 IPv4 IPv6/v4 9.50.174.237 34.87.46.224 SF18:2FTC:8874:ED42:47FE:EFCE:816:585 Figure 1.3 Mixture of IPv4 and IPv6 networks 108.53.213.226 B 240.47.136.34 IPv6 IPv6/v4 subnet B A77F:5478:8088:3E76:F5A1:0F83:4452:8299 141.255.243.82 IPv4 d 1.144.220.124