IPv6

What Is IPv6?

IPv6, also known as Internet Protocol version 6 or IP Next Generation (IPng), stands as a second-generation standard for network layer protocols. Within the network layer, where IPv6 operates, it furnishes connectionless data transmission services. The Internet Engineering Task Force (IETF) has conceptualized IPv6 as an upgraded iteration of IPv4, aiming to rectify several shortcomings present in its predecessor. The most notable distinction between IPv6 and IPv4 lies in the expansion of IP addresses from 32 bits to 128 bits. IPv6 positions itself favorably in upcoming markets due to its streamlined header, ample address space, hierarchical address structure, adaptable extension header, and improved neighbor discovery mechanism.

Why Do We Need IPv6?

IPv6 is deemed necessary due to the evolving landscape of networks and the limitations posed by the widely used Internet Protocol version 4 (IPv4). As a network layer protocol within the TCP/IP suite, responsible for facilitating the transmission of IP datagrams by utilizing the routing table, IPv4 has played a pivotal role in the early stages of the Internet. Its rapid adoption was fueled by a straightforward design, easy implementation, and seamless interoperability.

However, the swift growth of networks has outpaced the availability of IPv4 addresses, leading to a critical shortage. In response to this challenge, the IETF explored potential solutions, initially proposing drafts for IPv6, IPv7, IPv8, and IPv9. The objective was to find a successor to IPv4 that could accommodate the expanding demands of the network landscape.

Following extensive deliberation, the IETF ultimately selected IPv6 as the successor to IPv4, rendering IPv7, IPv8, and IPv9 drafts obsolete. This decision aimed to address the escalating demand for addresses and ensure the continued growth and functionality of the Internet.

Why Is IPv5 Unavailable?

In 1990, the IETF put forth the IPv5 draft with the initial expectation that it would handle streaming services, including voice and video. Simultaneously, IPv4 was envisioned to continue supporting data services. Despite these intentions, the IPv5 draft encountered various challenges and obstacles, preventing its widespread deployment and public usage. As a result, IPv5 has not seen significant adoption, and its intended role in carrying streaming services did not materialize as initially envisioned by the IETF.

What Is an IPv6 Address?

An IPv6 address comprises a network prefix and an interface ID. The network prefix, akin to the network ID in an IPv4 address, consists of n bits, while the interface identifier encompasses (128 – n) bits, similar to the host ID in an IPv4 address.

Structure of the IPv6 address

2001:A304:6101:1::E0:F726:4E58

The structure of an IPv6 address is 128 bits long and is represented as X:X:X:X:X:X:X:X, where each X represents four hexadecimal characters, separated by colons. The IPv6 address is segmented into eight groups. For simplification, an IPv6 address, such as FC00:0000:130F:0000:0000:09C0:876A:130B, can be abbreviated. Leading zeros in each group can be omitted (FC00:0:130F:0:0:9C0:876A:130B), and consecutive groups with only zeros can be replaced by two colons (::), resulting in the address FC00:0:130F::9C0:876A:130B.

Transitioning all systems from IPv4 to IPv6 in a short timeframe is impractical. The most effective solution involves embedding IPv4 addresses within IPv6 ones. The original 32-bit binary IPv4 address, expressed in dotted decimal notation (d.d.d.d), is converted into a special IPv6 address format X:X:X:X:X:X:d.d.d.d. Here, the first 80 bits are set to 0, the last 16 bits are set to 1, followed by the IPv4 address. For instance, if the IPv4 address is 192.168.0.1, the IPv4-embedded IPv6 address becomes ::FFFF:192.168.0.1.

IPv4 vs IPv6

With the rapid evolution of networks, the shortcomings of IPv4 design have become increasingly apparent. In contrast, IPv6 offers several new features and improvements.

IPv4 vs IPv6

Impact of IPv6 Deployment on Existing Networks and Services

1. Impact of IPv6 on Network Performance:

Enabling IPv6 on high-performance routers generally has minimal impact. It does not significantly affect network transmission delay or packet loss rates. In the event of a router failure, IPv6 has limited impact on the efficiency of updating information and calculating optimal paths.

2. Impact of IPv6 on Network Maintenance:

While deploying IPv6 increases the workload for network engineers and demands additional skills, it generally has a minor impact on overall network maintenance. Engineers familiar with IPv4 can quickly adapt to IPv6, minimizing the learning curve.

3. Impact of IPv6 on Services and Applications:

Existing services and applications on an IPv6 network remain unaffected. Moreover, IPv6 allows access to additional IPv6 resources. However, deploying IPv6 may necessitate adjustments in service systems, such as the domain name system (DNS). Incorrect configurations or defective software can impact user experience.

Association between IPv6 and the Domain Name System:

In an IPv6 network, each network device is identified by a 128-bit IPv6 address, which can be challenging to remember. To simplify access, an IPv6 domain name system is established. Users can use easy-to-remember domain names when accessing network devices. Servers on the network then resolve these domain names into corresponding IPv6 addresses.

Example:

Google's public domain name servers can map user-entered domain names to IPv6 addresses, such as:

2001:4860:4860::8888

2001:4860:4860::8844