【正文】 P/L, where T is the throughput, P is the packet size in kbits and L is the latency that corresponds to a packet of that size. The following ?gure plots the throughput for packet size ranging from 64 to 768 bytes. The packet size was kept less than 1440 bytes to avoid potential fragmentation problem in the IPv6 protocol stack. The maximum throughput is reached for largest packet size. The throughput generally increases with the increase in packet size. The overhead varies from 7% to 30% depending upon the packet size. The overhead decreases with increase in the packet size (Fig. 4). 7. Comparison with other mechanisms In this section, some related works proposed under IETF Next Generation Transition Working group (Ngtrans) (Waddington and Chang, 2020). 4 3 IPv4 Tunneled Latency 2 1 0 64 128 256 Packet Size 512 768 Fig. 3. Latency analysis. 6 Throughput (kbps) 2500 Throughput 2020 IPv4 Tunneled 1500 1000 500 0 64 128 256 512 768 Packet Size (bytes) Fig. 4. Throughput analysis. Dual stack (Bound and Tountain, 1999) mechanism is one of two basic transition mechanisms, which mandates the plete support for both IPv4 and IPv6 in hosts and routers. But it does not reduce the demand for globally routable IPv4 addresses and increases the work plexity due to the need for a mixture of IPv4 and IPv6 routing infrastructure. Application Level Gateway (ALG), SOCKS64 (Kitamura et al., 2020) and TCP Relay (Kitamura et al., 2020) are proxybased mechanisms which can provide munication between IPv4 nodes and IPv6 nodes. They all split one IP connection into two closed connections on application or TCP layer, one is in the IPv4 work and the other is in the IPv6 work. Their mon demerit is that they break the endtoend principle of the Inter, which is important aspect for emerce and business munications. ALG is an applicationdependent mechanism, which means for the different applications it should provide different application gateway ponents. SOCKS64 can only be for sites consisting of SOCKS aware clients and a SOCKS server. NATPT (Tsirtsis and Srisureshi, 2020) is derived from the traditional NAT (Srisureshi and Hodrege, 1999) mechanism, plus protocol translation between IPv4 and IPv6 protocol. BIS (Tsuchiya et al., 2020) adds an address translator module into the node’s system, cooperated with an address mapper and an extension to the name resolver, to facilitate the transition. SIIT (Nordmark, 2020) provides a ?exible and stateless translation between IPv4 and IPv6, but it is inplete since it does not specify how the packets with IPv4 translated IPv6 address to be routed in the IPv6 work. These three mechanisms can be thought as NATbased mechanisms, so they have the inherent NAT de?ciencies. NATunfriendly applications can not pass through the translator box without involvement of application level gateways. At the same time, NATbased mechanisms also have the same demerit as proxybased mechanisms as far as the endtoend munication is concerned. Further, any solution based on NAT boxes is inef?cient and not scalable. 7 8. Conclusion and future scope In summary the proposed prototype has many advantages that are listed below. IPv6 only hosts can reach corresponding IPv4only nodes on the Global inter. Being on a v6 only environment does not isolate the hosts from the rest of the Inter. Applications not yet IPv6ready can be run over IPv6only hosts and works. Network is con?gured for IPv6 only. There is no need to con?gure addresses and routes for IPv4. Any type of protocol/application can be transparently forwarded. No need to con?gure translators. The prototype assumes that the IPv6 nodes have both IPv4 and IPv6 addresses available. In future when the nodes are upgraded to IPv6 domain, then the IPv4 address would be required only on a temporary basis only to municate with IPv4 only nodes. A mechanism is required to detect the need of an IPv4 address for an IPv6 node. This mechanism would require snooping at the kernel level, tracing the IPv4 API system calls. Consequently a procedure is needed to obtain an IPv4 address from a server. The procedure utilized may be DHCPv6 or RPCv6 or any other speci?cally designed for the purpose. Similarly a server would be required for maintaining global IPv4 addresses. References Af??, H., Tountain, L., ENST Bretagne, Methods for IPv4IPv6 Transition. IEEE 1999. Bound, J., Tountain, L., Af??, H., Dupont, F., Durand, A., dual stack transition mechanism (DSTM) Inter draft (draftietfngtrans ) 2020. Chakeres, ., AODVUCSB Implementation, University of California Santa Barbara. / Davies, J., Introduction to IP version 6 Mic