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IP Version 6 FAQs

Last Updated: Thu, 23 Jan 2014 > Related Articles

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IP version 6 (IPv6) is the newest version of the Internet Protocol that allows for continued Internet growth over the existing IP version 4. View general information about this newest Internet Protocol.


Cox is working diligently to ensure all networks, systems, and products are fully IPv6-enabled in preparation for IPv4 address exhaustion and a gradual adoption of IPv6 by the internet at large. To manage this migration, Cox has established an IPv6 Migration Program so that when the IPv4 addresses are exhausted, we will continue our business operations without interruption.

IPv4 vs. IPv6

IPv4 and IPv6 addresses are not compatible. A computer configured with an IPv4 address is unable to communicate with a computer or website that is configured with an IPv6 address.

We have created a short video to explain the IPv6 transition. Click the button below to view it.

Launch Video

What is IPv4?

IPv4 or Internet Protocol version 4 is the communication protocol used on the Internet for over 30 years. It is commonly recognized by its address notation of

What is IPv6?

IPv6 or Internet Protocol version 6 is the successor to the Internet Protocol version 4 offering a vastly expanded address space, simplified header, and an auto-configuration option among other features.

How does the new IPv6 address differ from the IPv4 address?

IPv6 addresses are 128 bit where IPv4 addresses are 32 bit.

  • IPv6 address: 2001:0578:0123:4567:89AB:CDEF:0123:4567
  • IPv4 address:

Why could the IPv4 address not be expanded with additional octets?

Many proposals for the next-generation Internet Protocol were proposed and debated in the early 90s to address the IPv4 address shortage. The final compromise was for a 128 bit address schema supporting a base 64 bits for Interface addressing and another 64 bits for subnets. The amount of work to add two additional octets to IPv4 would have been equivalent to the amount of work to do IPv6.

IPv4 Exhaustion

What is IPv4 exhaustion?

The current Internet Protocol version 4, supports only 4.2 billion unique addresses in total. This numbering schema, which has been used on the Internet nearly 30 years, is quickly approaching the end of its number of unassigned Internet addresses. As a result, there will be a time in the near future where no more new IPv4 addresses can be allocated.

Why are IPv4 addresses used up so quickly?

The explosion in demand worldwide for devices such as laptop, desktop, and wireless devices able to communicate instantaneously using the public Internet has resulted in the rapid depletion of available Internet addresses. In addition, there are inefficiencies in the way that IP addresses have been allocated in the past, which decreased the total available pool size.

Who is impacted by IPv4 exhaustion?

All Internet Service Providers are faced with providing a migration path from IPv4 to IPv6 for all their customers. Cox is working to ensure that the impact to our customers will be minimal.

When will we run out of IPv4 addresses?

Cox is no longer receiving new allocations of public IPv4 addresses from ARIN, the North American Regional Registry. However, due to some re-allocations of Cox’s existing IP addresses space, we can continue providing IPv4 addressing to our customers while we introduce support for IPv6 in parallel.

What is Cox doing about IPv4 exhaustion?

Cox has established an IPv6 Migration Program to make sure that all Cox networks, systems, and products have IPv6 compatibility so that when the IPv4 addresses are exhausted, we will continue our business operations without interruption. We are in the process of developing the IPv6 migration plan for all of products and services.

How do I know if I am affected by IPv4 exhaustion?

If you are a current Cox High Speed Internet residential or Cox Business customer, you will not be impacted by IPv4 exhaustion in the near term. If you have Cox Optical Internet Service and have a need to implement IPv6 in the near future, you should contact your local Account Executive or System Engineer.

Cox Plans for IPv6

There are many IPv4 and IPv6 "transition" technologies that enable IPv4 and IPv6 host to communicate with each other. Cox has chosen "dual stack" as our transition method. In "dual stack", every networking device, computer, server, switch, router and firewall in the Cox network will be configured with an IPv4 and an IPv6 address, meaning "dual stacked." This enables Cox to process either IPv4 and/or IPv6 traffic at the same time.

Will I be affected when Cox changes to IPv6?

Cox is planning to fully support IPv6 in a way that is transparent to the customer experience. For customers with IPv6 capable devices and software, IPv6 will need to be enabled in your home equipment, if it is not enabled by default. When the Cox network is completely IPv6 enabled, Internet experience will be provided using a mix of IPv4 and IPv6, but in a way that is transparent to the end-user.

What do I need in order to utilize IPv6?

IPv6 is not supported on all customer equipment, so in order to receive IPv6 addressing and communicate with other IPv6 devices on the Internet, the following are needed:

  • A DOCSIS 3.0 cable modem, WiFi Modem, or WiFi Internet & Telephone modem. If using a standalone router, it must be IPv6 capable.
  • A computer operating system, such as Windows 7, that is capable of IPv6.

When will the Cox network be upgraded to IPv6?

Cox is working diligently to ensure all networks, systems, and products are fully IPv6-enabled in preparation for IPv4 address exhaustion. Cox began deployment of IPv6 on the Cox High Speed Optical backbone early in 2009 and is now in the process of enabling IPv6 throughout the remainder of the network.
Network upgrades in the markets have started and are expected to be completed by year end 2014. Residential customer trials are planned for 2014. Stay tuned for more announcements.

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