The 5 Main Concerns In Implementing Ipv6

Published Date: 02 Nov 2017

The Internet provides unlimited connectivity, but in order to provide this connectivity necessitates that the computers and other devices are able to establish a connection using a common addressing scheme. The Advanced Research Projects Agency Network (ARPANET) was the world's first operational packet switching network, to use only TCP/IP and IPv4 addressing on January 1, 1983. (Hauben, 1998) With the depletion of addresses recognized in the 1990’s a new addressing scheme was developed called IPv6. IPv6 is being put into place to accommodate with the growth of the Internet. These questions need to be asked:

Why IPv6 is needed?

What is IPv6?

How to Subnet IPv6?

What are the 5 main concerns in implementing IPv6?

What are ‘best practices’ to implement IPv6?

Why IPv6 is needed

Internet Protocol (IP) addressing is the IPv4 is the most commonly used version of addressing. IPv4 addresses are 32-bit numbers often expressed as 4 octets in "dotted decimal" notation. (IANA, 2013) By the end of the 1980’s it became increasingly obvious that the 4,294,967,296 ( addresses that were available were not going to sufficient to supply the explosive growth in the Internet’s acceptance. The number of devices that would need to link to the Internet using an address far exceeds the available addresses. The Internet Engineering Task Force (IETF) develops and promotes Internet standards, cooperating closely with the W3C and ISO/IEC standards bodies and dealing in particular with standards of the Internet protocol suite (TCP/IP). (Russell & Cohn, 2012)

When the depletion of the IPv4 address was obvious in the 1990’s the IETF was tasked with devising a new addressing scheme. While IETF was working on the new IP version several workarounds were put into place to slow the depletion of the IPv4 address. The following stop gaps insured that the address space would last till a viable solution could be put into place.

Establishment of Private Network Addresses (RFC 1918)

Establishing gateways

Network Address Translation (NAT)

These protocols provided companies and network administrator’s time before they would have to implement the IPv6. This time was to allow for a smooth transition and not be a permanent solution to the address depletion. Without adding these protocols to the IPv4 addressing scheme the address space would have been used up prior to IPv6 being ready for deployment. RFC 1918 defined has reserved the following three blocks of the IP address space for private internets:

10.0.0.0 - 10.255.255.255 (10/8 prefix)

172.16.0.0 - 172.31.255.255 (172.16/12 prefix)

192.168.0.0 - 192.168.255.255 (192.168/16 prefix)

Private network addressing allowed an administrator to assign internal IP addresses to computers running on their internal network by using these address blocks. (Rekhter, Moskowitz, Karrenberg, Groot, & Lear, 1996) Then a gateway would be defined and with NAT running on the edge of a network would change the IP address to the company’s external address or from a group of addresses that are assigned to the company with a port translated to the connecting computer. These measures preserved address space being assigned by IANA delaying the complete depletion of address space available within the IPv4 address space. IANA is the entity that coordinates global IP address allocation, root management of the Domain Name System (DNS) and other Internet Protocol-related symbols and numbers. (IANA , 2013)

IANA assigns the available blocks of IP addresses to the five regional internet registries that in turn divide the addresses into smaller blocks and delegate them to Internet Service Providers and other organizations. "On Monday, January 31 2011, IANA allocated two blocks of IPv4 address space to APNIC, the Regional Internet Registry (RIR) for the Asia Pacific region, which triggered a global policy to allocate the remaining IANA pool equally between the five RIRs. Today IANA allocated those blocks. This means that there are no longer any IPv4 addresses available for allocation from the IANA to the five RIRs." (NRO: The Number Resource Organization, 2011).

What is IPv6

In 1996 IETF developed IPv6 to expand the number of IP addresses available. IPv6 addresses are 128-bit addresses, expressed in hexadecimal notation (for example, 2001:DB8:8::260:97ff:fe40:efab). ( RIPE Network Coordination Centre, 2010) RFC 2460 published in December 1998 became the standard for the IPv6 protocol. With the development of the IPv6 protocol a viable replacement for IPv4 was found.

The internet has exploded with the growth of mobile devices that need to link with the internet and IPv6 will accommodate this growth. Because IPv6 and IPv4 are built upon a similar structural design, a majority of operational transport layer protocols that function within the IPv4 protocol will also function with the IPv6 protocol. Most application layer protocols are expected to be able to function with IPv6 as well, but, there are exceptions most notably File Transfer Protocol (FTP). FTP uses embedded network layer addresses to facilitate data transmission. Covering the main reason for its development IPv6 will increase the address space available. The 128-bit length of IPv6 addresses will allow for an almost unlimited number of unique IP addresses.

Subnetting IPv6

An IPv6 address consists of eight groups of four hexadecimal digits. If a group consists of four zeros, the notation can be shortened using a colon to replace the zeros. When ARIN supplies a company an IPv6 address they will typically assign a number for example 2FFB:1000:2000::/48. With this assignment we cannot change these 48 bits that are the network bits. Typically with IPv6 we would reserve the last 64 bits as the host bits leaving 16 bits for the subnet that can be assigned in hex from 0000 to FFFF allowing for a combination of 65,000 subnets. Each of these subnets you can have available for hosts.

2FFB:1000:2000:_____:____:____:____:____

Network Subnet Host

Host portions of the address can be assigned in a number of ways dynamically or manually. The IETF has issued RFC 2462 to set guidelines for IPv6 auto-configuration defined as EUI64. The EUI64 method would dynamically assign the host with an address using its unique mac address of the network interface card. The mac address of 00-24-C1-96-AD-E9, EUI64 will take the first 8 bits in binary and change the second to least significant bit to a 1. (00 is written in binary as 0000 0010) This would change the first portion of the mac address to 02. In IPv6 leading zeros are dropped so using EUI64 on next field on the address would be 224. The next field will start with C1 and because a mac address is only 48 bits long will require padding to complete the address FF:FE will follow starting the next 16 bits. Then rest of the mac address will complete out the IPv6 EUI64 address. (Example 2FFB:1000:2000:1000:224:C1FF:FE96:ADE9 would be the final address of the device.) . Manually best practice is to use is by assigning a number in the last field of the host. (Example, 2FFB:1000:2000:1000::42) As with anything that is new there are many concerns by individuals and companies as in how to migrate to the new IPv6 addressing format.

Concerns implementing IPv6

With the ultimate depletion of IPv4 address from the pool soon companies will have no other choice but to convert their systems to IPv6 just maintain internet connectivity. The only addressing they will be able to get is an IPv6 address from their ISP. It is only a matter of time, the clock is ticking. The migration to IPv6 will be a complicated one for all organizations. There are scans of existing equipment to do, information to gather, and plans that need to be made through the organization to accommodate these concerns. Most of the concerns will be answered by the network administrators and the IT teams that companies have in place. 6connect.com published an article on February 8, 2012 outlining the following top five concerns of that network administrator have about making the switch to IPv6:

Selling the migration internally to the decision makers

The cost of migrating

Complexity of migrating

Dealing with legacy system issues

Removing current IPv4 devices

Selling the Migration Internally to within an organization, the organization will rely upon the IT professional. Corporate decision makers must know exactly what is at stake in the migration and what it means for the organization. Results must be conveyed along with the consequences that are surly going to be part of the process of migrating to IPv6. Once the communication of why the migration is to be done the decision makers can then look at the costs that will be involved with such a task.

The cost to a corporation is not only the amount of money will spent on the project but, also, the time and personnel that will be involved. An exorbitant amount of planning is going to be required to complete the migration as quickly as possible, and having connectivity with hardware/software working as an end result. Trained personnel that can be efficient at their tasks, communicate well, and have different experience and points of view will help reduce the overall cost. By far the costliest will be the new equipment needed to perform the specific IPv6 functions, or for new equipment to replace non IPv6 compatible. In an article published by Greg Ferro on March 7, 2011 he states, "Implementing IPv6 will require significant resources, extensive planning and commitment to implementing change." Ferro continues, "The migration to IPv6 means upgrades to data center equipment, but also significant changes to desktops, security and compliance software, network management systems, WANs, telecommunication strategies, IP telephony and more." (Ferro, 2011) With these changes needing to be made the complexity issues with a migration to IPv6 seems to be very formidable road block to complete the process.

With migrating to IPv6 complexity, all departments of an organization will be effected from the president, management personnel to the end users, and all equipment used on the corporate network. The best way to approach the complexity issues is to have a plan that has been and communicated throughout the organization. The plan should be broken up into manageable tasks that can be accomplished one at a time. Legacy system devices and applications add to the complexity, the administrator will have to insure that all mission essential applications and hardware are compatible with IPv6.

Legacy systems can be defined basically as older systems. They likely are missing some common functionality from current technology, but still exist because they perform a key or important function for the organization just fine, thus there is no reason to replace it. With IPv6 migration, there may be a reason now to update older systems and application to be compatible with emerging technologies. To accommodate this an organization will need to have an IPv6 address, along with their existing IPv4 address (a technique known as dual-stacking). If a device is not able to use a IPv6 address, it will sooner or later cause conflicts and problems by not being able to communicate properly with newer devices. As the network moves further into the migration legacy devices will lose more and more communication with the network until it is gone. It is inevitable that an important piece of equipment will not be compatible with the IPv6 addressing. Identifying the equipment or applications that are not compatible with the IPv6 scheme leads us to the fifth concern is to clean of current IPv4 inventory.

For many network administrators doing away with of IPv4 equipment will involve getting new equipment, implementing it, hanging onto the old equipment temporarily for backup purposes, then getting rid of it. But it is more than just equipment. Inventory in this case should also include services such as DNS and DHCP, both of which change or are removed with IPv6. Without the capability to communicate with v4, the devices will simply not function and do not pose a threat to the network connectivity or as a security risk. However, at this point it is less about the plan itself, and more about executing it. By this stage, dual-stacking should be fully implemented and all non-compatible devices either replaced or their purpose moved to a compatible device. Then DHCP can be turned off for IPv4 and all devices with static addresses having their IPv4 addresses removed. This is where the concern comes in. If one device is missed at this point, it will immediately lose all communication with the network if it has not already. The addition and sheer volume of devices this may have to be done for, and suddenly the scope grows even more.

https://6connect.com/resources/top-5-Concerns-of-network-admins-about-migrating-to-ipv6

‘Best Practices’ to implement IPv6

IPv6 is nearly a decade old yet according to Google IPv6 prevalence is still low, but the numbers are growing by the week.