Dear Professor Phil,
I’ve heard a lot about the change from IP version four to IP version six. Is it really a big deal to AV professionals?
Ben, Atlanta, GA
Yes, it is a really big deal. Many people think that the significant issue is the change in the size of the IP address. It’s changing from four bytes to sixteen bytes. However, the implication of the version change goes much farther. Every IP version six (IPv6) data packet on the network, whether carrying voice, video or data, will be formatted differently. This means that network interface cards, routers and system protocol stacks need to interpret the IP information under new rules. There are fields within IP being dropped and other fields added.
The version change will more significantly affect hardware devices that can’t be upgraded. For example, a current IPv4 device knows to search for the IP source address in bytes 15-18 of the Ethernet frame. It looks for the destination IP address in bytes 19-22. In IPv6, the device would need to find source address in bytes 15-30. The destination address would follow in bytes 31-46. A device hard coded to search for a version four address would be useless with version six traffic. Of course, if the firmware is upgradable in the device, the problem might be overcome.
Two other significant issues will be the use of hexadecimal in documenting addresses and multicasting. My experience has been that hexadecimal numbers are very confusing to technicians. It will be important for them to understand hexadecimal before encountering IPv6 addresses because they will often be documented in hexadecimal. Also, multicast addressing, which is heavily used in video, is entirely different in the new version. It, too, will require some study and thought before using it.
Phil Hippensteel, PhD, is a professor of information systems at Penn State Harrisburg.