The IPv4 address defined by IETF in RFC 791 published in 1981. The first design of IPv4 does not expect the growth of the internet and this created many issues, which proved IPv4 need to be changed. Through the years, IPv4 has updated to address new challenges. However, IPv4 has still some major issues which we listed below.
Shortage of IPv4 Addresses
The IPv4 addressing uses 32-bit address space. This 32-bit address space is further classified into A, B, C, D and E classes. These classes have a limited number of unique public IPv4 address which is about 4 billion. while there are, the increasing number of new IP-enabled devices, always-on connections, and the potential growth of less-developed regions have increased the need for more addresses.
Security Related Issues
As we discussed earlier that IPv4 addresses published in 1981 and the present network security issues were not projected at that time. Internet Protocol Security is a protocol suite which enables network security. Internet Protocol Security provides security for IPv4 packets, but it is not built-in.
Address configuration related issues
Internet routing table expansion
A router, routing table select the best path for communication. Because of the number of servers connected to the Internet increases which also increase the number of a route. These IPv4 routes use a memory and processor resources on Internet routers.
Lack of end-to-end connectivity
Within IPv4 network, NAT is generally used. NAT makes possible to give a way for multiple devices to share a single public IPv4 address. This is difficult for technologies that need end-to-end connectivity. Because the public IPv4 address shared and the IPv4 addresses of an internal network host remain hidden.