Welcome to IPv6. This day around the world marks the commitment by industry to deploy IPv6. ISP's, home networking equipment, and web companies will enable IPv6 in their products and services. This is a staged roll-out. ISP's have committed to providing IPv6 to at least 1% of their customers to start. Home network manufactures will enable all new products to use IPv6. It is expected as users upgrade their network hardware the IPv6 percentage will grow. IPv6 was enabled and tested by major web companies last year, so web companies are ready to enable IPv6 on their sites.
The old IPv4 addresses, like 172.16.254.1, will gradually go away. The problem was, or is, the growing need for IP addresses from mobile phone users and wireless connections has used up the four billion addresses that are possible with IPv4. IPv6 has the capacity to have 340 Trillion addresses. With the world's population currently standing at 6,840,507,000 trillion. This would give each person on earth 50 connections before a new limit would be reached. A number that leaves plenty of room for the Internet to expand, hopefully, over the next 100 years.
The new IPv6 address will be considerable longer, consisting potentially of 8 four digit numbers. Here's an example of an IPv6 address: FE80:0000:0000:0000:0203:b3dd:FE1E. This is an 128 bit address, where as, IPv4 was a 32 bit address. In the IPv6 example here, when using the address the 0000 sets can be omitted, leaving the example IPv6 address as Fe80::203:b3dd:FE1E. Leading 0000 can be omitted, a group of consecutive 0000 can be replaced with a double colon. So a loopback address of, 0:0:0:0:0:0:0:1 can be shortened to ::1.
IPv4 addresses were poorly allocated. The address space utilization will be small in IPv6 and network management and routing efficiency will be improved by the large subnet space and hierarchical route aggregation. IPv6 also enables multicasting or the transmission of packets to multiple destinations in one send operation. Mobile IPv6 is more efficient for mobile devices avoiding the triangular routing used be IPv4.
The packet header in IPv6 is different. It is 320 bits that contains the source and destination address, traffic classification options, a hop counter, and a pointer for extension headers. Routers will never fragment a packet, like they did in IPv4. This make IPv6 potentially more secure, making it much harder for hackers to remain anonymous. IPv6 incorporates your real MAC address into the IPv6 address so if you download some copyrighted material you would be able to be identified. Some initial threats to the use of IPv6 is incompatible firewalls, intrusion-preventions devices, and other security devices will have growing pains as they adapt. If the security devices are turned off to enable IPv6 addresses, it may become easier, not harder, for hackers to penetrate networks. There will be some growing pains as hackers exploit IPv6 vulnerabilities during the roll out, and the vulnerabilities are fixed.
IPv6 is here to stay with major companies like Cisco, Facebook, Microsoft, Google, AT&T, Comcast, and Time Warner cable all committing to the roll out starting today. Because of the gradual roll out, IPv4 will work right along side IPv6 for the foreseeable future. This will cause a minimum of problems as the roll out proceeds.