IPv4 versus IPv6: comparative analysis and deployment considerations

IPv4 versus IPv6

The explosive growth in the number of devices that are connected to the Internet has placed enormous pressures on the system's infrastructure. The current Internet protocol addressing system is projected to be inadequate to handle the increased number of telecommunications devices that are expected to be in use in the coming years, and engineers have taken steps to accommodate these increases in use through a new protocol known as IPv6.* This paper provides an overview and history of IPv4 and IPv6 and a comparison of the two technologies, followed by a summary of the research in the conclusion.

What is IPv4?

According to IPv4 (2005), "IPv4 is version 4 of the Internet Protocol (IP). It was the first version of the Internet Protocol to be widely deployed, and forms the basis for most of the current Internet"; the IPv4 protocol was first described in Internet Engineering Task Force Request for Comments No. 791, published in September, 1981 (p. 1). Remaining much as it did when it was first developed over 20 years ago, IPv4 has supported the growth of the Internet to its current global proportions (Lee & Stewart, 2005).

B.

IPv4 address shortage. According to Patrick (2001), "Today's Internet is not prepared to handle the billions of devices that will be connected over the next few years. The capacity has been steadily growing and the advent of pervasive optical fiber will likely meet the demand. However, we will soon run out of addresses for all the devices" (p. 86). This address shortage is caused when users connect to the Internet and are assigned a temporary Internet protocol (IP) address; the Internet protocol is foundation upon which Internet is built. The IPv4 employs a four-part address for each device, such as 64.252.14.121, for instance (Patrick, 2001). Each component of the IP address can be between 0 and 256. Patrick points out that 256 times 256 times 256 provides in excess of 4 billion globally unique addresses; while that may appear to be sufficient, in reality, the number is considerably smaller because of the inefficient way in which the addresses are allocated. "Even at 4 billion, it is not enough," Patrick says, and "Cell phones alone are projected to be in the billions" (p. 86).

What is IPv6?

A.

History. Most of today's internet uses IPv4, however, because of its growing shortage of IPv4 addresses, the addresses will run out in about year 2008; in an attempt to remedy this shortfall, a new set of protocols was proposed by numerous internet groups such as "CNAT," "Nimrod" and others in 1993 and by 1995, and a basic specification was established (Internet Protocol Version 6, 2004).

B.

Need for IPv6. The new Internet Protocol version 6 ("IPv6") will gradually replace the existing Internet protocol, IPv4. The newly approved version of the IP standard is called IPv6, or IP "next generation" (Patrick, 2001). The new standard has "2 to the 128th power addresses which provides more than 50,000,000,000,000,000,000,000,000,000 addresses per person! If you look at it by surface area, it would be approximately 340,000,000,000,000,000,000,000 addresses per square meter of the planet! That should be enough!" (p. 87). The IPv6 standard requires software to include a globally unique identifier GUID in the header of every Internet communication (email, web browsing, chat, and others) (Froomkin, 2000). According to Froomkin, "Computers with an ethernet card would create a GUID by combining the unique ID number assigned to the card's manufacturer with a unique number assigned to the card in the factory. Thus, every packet you send out onto the public Internet using IPv6 has your fingerprints on it. And unlike your IP address under IPv4, which you can change, this address is embedded in your hardware. Permanently" (p. 1462). In his book, Net Attitude: What It Is, How to Get It, and Why Your Company Can't Survive without It, Patrick (2001) reports that "IPv4 has lasted twenty years but needs to be replaced" (p. 86). Beyond the additional addresses provided by the IPv4 approach, there are other benefits as well. These are discussed further below.

IPv4 versus IPv6. The fundamental constraint to IPv4 is an inadequate address field (32 bits), and even this capability is not used effectively (Internet Protocol Version 6, 2004). Anderson, Botterman and Cave et al. (2003) point out that, "IPv6 is necessary for effective broadband scaling and security and is a precondition for effective 3G mobile access to broadband networks" (p. 76). According to Patrick (2001), "IPv6 includes other benefits and simplifies end-to-end security. This will become very important for conducting e-commerce transactions" (emphasis added) (p. 87). The IPv6 also provides an improved option mechanism that are placed in separate extension headers located between the IPv6 header and the transport-layer header in a packet. The two key improvements of IPv6 over IPv4 are: