IPv6 tutorials free ipv6 study guide free What is IPv6

IPv6 tutorials free ipv6 study guide free What is IPv6

No matter for which certification are you preparing IPv6 has become the essential part of all major certifications. In order to get IT certification you must be familiar with IPv6. With a complete series of article on ipv6 tutorials we have tried our level best to give you whatever universal certifications require from IT professionals.

The current version of IP (known as version 4 or IPv4) has not changed substantially since Request for Comments (RFC) 791, which was published in 1981. IPv4 has proven to be robust, easily implemented, and interoperable. It has stood up to the test of scaling internetworks to a global utility the size of today’s Internet. This is a tribute to its initial design. 
However, the initial design of IPv4 did not anticipate the following:

Limitations of IPv4

The recent exponential growth of the Internet and the impending exhaustion of the IPv4 address space

Given that an IP address is 32 bits in length, there are 232 actual IP addresses, which are 4.3 billion addresses. Only 3.7 billion of these are actually usable. Many addresses are reserved, such as the research (239–254), broadcast (255), multicast (224–239), private (10, 172.16, and 192.168), and loopback addresses (127). And, of course, many of the usable addresses are already assigned, leaving about 1.3 billion addresses for new growth. As a result, public IPv4 addresses have become relatively scarce, forcing many users and some organizations to use a NAT to map a single public IPv4 address to multiple private IPv4 addresses. Although NATs promote reuse of the private address space, they violate the fundamental design principle of the original Internet that all nodes have a unique, globally reachable address, preventing true end-to-end connectivity for all types of networking applications. Additionally, the rising prominence of Internet-connected devices and appliances ensures that the public IPv4 address space will eventually be depleted.

The need for simpler configuration

Most current IPv4 implementations must be either manually configured or use a stateful address configuration protocol such as Dynamic Host Configuration Protocol (DHCP). With more computers and devices using IP, there is a need for a simpler and more automatic configuration of addresses and other configuration settings that do not rely on the administration of a DHCP infrastructure.

The requirement for security at the Internet layer

Private communication over a public medium such as the Internet requires cryptographic services that protect the data being sent from being viewed or modified in transit. Although a standard now exists for providing security for IPv4 packets (known as Internet Protocol security, or IPSec. This standard is optional for IPv4 and additional security solutions, some of which are proprietary, are prevalent.

The need for better support for prioritized and real-time delivery of data

Although standards for prioritized and real-time delivery of data—sometimes referred to as Quality of Service (QoS)—exist for IPv4, real-time traffic support relies on the 8 bits of the historical IPv4 Type of Service (TOS) field and the identification of the payload, typically using a User Datagram Protocol (UDP) or Transmission Control Protocol (TCP) port. Unfortunately, the IPv4 TOS field has limited functionality and, over time, has been redefined and has different local interpretations. The current standards for IPv4 use the TOS field to indicate a Differentiated Services Code Point (DSCP), a value set by the originating node and used by intermediate routers for prioritized delivery and handling. Additionally, payload identification that uses a TCP or UDP port is not possible when the IPv4 packet payload is encrypted. To address these and other concerns, the Internet Engineering Task Force (IETF) has developed a suite of protocols and standards known as IP version 6 (IPv6).