Home » Technology » (IPv6) Internet Protocol Version 6

(IPv6) Internet Protocol Version 6

  • What does IPv6 Internet Protocol Version mean?
  • Internet Protocol Version 6 (IPv6), in short, was developed by the IETF on the fact that IPv4, which actually has a 32-bit address structure, is no longer available for addressing and causing serious bottlenecks.

 

  • It was not calculated that the Internet would go so far when IPv4 was created. However, the widespread use of the Internet and the emergence of new devices (mobile phones, telephones, digital photocopiers, etc.) that require an IP address (Internet Protocol, ip address) have caused existing addresses to be inadequate. Now, when the addressing problem occurs, it is inevitable to switch to IPv6, which is a 128-bit address structure. This time it is an address structure created with a lot of thought in mind. There will be an unlimited address range in the new address.
  • In IPv6, addresses are composed of 8 octets and 16 (sixteen) bases are represented. 128 bits are divided into 16-bit parts (octets). Each octet is converted to hexadecimal. And they are separated by a colon (:).

 

  • 21DA: 00D3: 0000: 2F3B: 02AA: 00FF: FE28: 9C5A IPv6; Authentication and location of computers on the network.

 

  • IPv6 Addressing Mechanism
  • In IPv6, the addressing architecture and address structure have changed considerably, as well as the 128-bit address length; In the writing of addresses, it is generally preferred to use the notation of the 16th position. For example, here are two typical IPv6 addresses. As you can see, each group of four characters is separated by a “:” character. Since each character is represented by 4 bits on the 16th pad, the four characters are 16 bits in total. That is, the 16 bit address bits consist of 4 (four) characters and are separated by “:”. Therefore, in an IPv6 address, there are 8 (eight) parts, each consisting of 16 bits.

 

  • a) 1234: 5678: 9ABC: DEF0: 1234: 5678: 9ABC: DEF0 b) 1999: 6: 13: 0: 0: 1962: 2: 15

 

  • Two different IPv6 (a and b) addresses have been given above. It is not necessary to write all the characters in the upper (a) address while the left characters of the 4 (four) characters are zero (0), as shown in the bottom (b) address. If all four-character parts are zero, one zero is written and if there are more than one parts, a special abbreviation can be used. For example, the following are shown in full spelling and abbreviated spelling:

 

  • 1999: 6: 13: 0: 0: 1962: 2: 15 → abbreviated → 1999: 6: 13 :: 1962 :: 2: 15
  • 0: 0: 0: 0: 0: 0: 0: 1 → abbreviated →: 1
  • 0: 0: 0: 0: 0: 0: 0: 0 → abbreviated → ::
  • FF01: 0: 0: 0: 0: 0: 0: 101 → abbreviated → FF01 :: 101

 

  • In addition to addressing the next generation protocol, there is also a change in address type and communication patterns. The new generation of broadcast-type forwarding, which is used extensively in IPv4 today and brings together some problems for network specialists, has been removed in the routing protocol. The address types in IPv6 are as follows:

 

  • Unicast: A node can be assigned to an interface; This is a singular situation and it makes the interface identity-possessed. However, the same interface can have multiple IPv6 addresses. For example, such a situation can be used for band combining of two different communication channels. However, a single-address can be assigned multiple interfaces; So that it becomes an “addressable” address, not a one-sided address.
  • Anycast: Adrenalin assigned multiple interfaces. If the IP packet arrives first of all, the packet goes to it. That is, a package sent to any recipient adrese will be delivered to the nearest interface with this adrese.
  • Multicast: An address type that can be given multiple interfaces. This adrese goes to all the interfaces that a given package address is assigned to. Multihomed addressing also addresses the need for broadcast-type addressing.

 

  • Addressing Model
  • A device, identified as at least one address in the IPv6 network backbone, is seen as a system “node”. However, IPv6 addresses are assigned to interfaces rather than nodes. A node can have one interface and multiple interfaces. In short, IPv6 addresses are assigned to interfaces. If a node has one interface, that address is also the node address. More than one IPv6 address can be assigned to an interface; These addresses can be single-recipient, any recipient or multi-recipient.

 

  • The traffic occupying packet headers in IPv4 have been removed and a speed increase has been made. In addition, more secure transmissions are provided with newly added encryption systems. AH and ESP headers are available to facilitate encrypted transmission between the ends. The AH and ESP headers are used to support the IPSec protocol, which encrypts all data transmissions between the ends.
  • Also, at this time, IPv4 will be solved with IPv6, the problem of image and voice transmission, which is managed by QoS addition but can not be fully supported. IPv6 assigns a “priority packet” to video and audio packets, allowing them to prioritize traffic.
  • ipv4 ipv6

    ipv4 ipv6

  • IPv6 addresses. A 32 bit address (IPv4) structure means
  • ipv4 ipv6

    ipv4 ipv6

  • Means IPv4 address.

 

  • To send data to a group of devices is called multicast. Broadcast is the sending of data to all devices on the network. When data is broadcast, an intensive network traffic occurs. IPv6 does not have broadcast transmission. This reduces the traffic on the network and makes it easier for attack attempts to be prevented (it can also be used as an attack because there is no authentication in the ARP and DHCP protocols). It uses IPv4 broadcast communication mostly in ARP and DHCP protocols. In IPv6, the equivalents of ARP and DHCP protocols use multicast communication. There are three distribution types in IPv6; Unicast (single distribution), anycast (any distribution), multicast (multiple distribution).

 

  • The IPv6 host addresses themselves can be configured automatically when ICMPv6 router discovery messages are connected to the Neighbor Discovery Protocol (NDP) IPv6 network.

 

  • IPSec (an extension of the IP protocol that provides security for IP and higher layers) was first developed for IPv6, but was later also designed for IPv4.

 

  • Compared to IPv4, the most important advantage of IPv6 is its wide address space. IPv4 addresses are 32 bits long and are around 4.3 billion. The ipv6 addresses are 128 bits long and are about 340 deciles (10 ^ 36 times a million times). IPv6 addresses are assumed to be sufficient for the foreseeable future.

 

  • IPv6 addresses are written in 8 groups of 4 separated by commas, 2001: 0db8: 85a3: 0000: 0000: 8a2e: 0370: 7334. IPv6 unicast addresses begin with 000 digits and are divided into 2 parts: the first 64 bits subnet prefix and the second 64 bit interface identifier. For stateless address autoconfiguration (SLAAC) operation, subnets require a 64-block address as defined in RFC 4291 section 2.5.1. Local internet recorders take at least 32 blocks separated. This block is divided between ISPs (internet service providers). The old RFC 3177 Recommendation / 48 has been assigned to the end user side. This has been replaced by RFC 6177, which promises to give more than a single / 64 bit to the client side, but it is not foreseen that each house can be given either 48 or 56 bits in specially.

 

  • ISPs (internet service providers) seem to agree with this forecast. In the initial release, Comcast customers were given a single / 64 network. IPv6 addresses are classified with 3 types of network metrology. Unicast addresses define each network link interface, anycast addresses define group link interfaces, usually the closest channel interface is automatically selected at different locations, and multicast addresses are used to distribute multicast addresses across multiple link interfaces. The broadcast method is not implemented in pv6.

 

  • Each ipv6 address has a designated area within a piece of valid and unique network. Some addresses are unique only on the local network. The others are universally unique. Some ipv6 addresses are reserved for certain groups; Such as loopback, 6to4 tuning and Teredo tuning. These are specified in RFC 5156. Addresses such as link-local addresses, which are taken into account at some address ranges, use only Unique Local Addresses (ULA) on the local connection. ULA is defined in RFC 4193, and the querying host (solicidet-node) multicast addresses (Neighbor Discovery Protocol) are used in the Neighbor Discovery Protocol.

 

  • Custom IPv6 addresses
  • The following addresses are specific IPv6 addresses:

 

  • Unspecified addresses:
  • Unspecified addresses (0: 0: 0: 0: 0: 0: 0: 0 or: : ) indicate that only one address does not exist. This address is equivalent to the address 0.0.0.0 in the IPv4 version. The unspecified address is typically used as the source address before the unique address is set. An unspecified address is never assigned as an interface or used as a destination address.

 

 

 

 

 

  • Loopback address
  • The loopback address (0: 0: 0: 0: 0: 0: 0: 1 or :: 1) is used to specify a loopback interface that enables a node to send packets to itself. This address is equivalent to the 127.0.0.1 address in the IPv4 version. Packets must not be sent or forwarded to the Loopback address through the IPv6 router.

 

  • General Security Concepts
  • In order to protect the data, you need to be aware of possible Threads. People often focus only on malicious attacks from foreign networks. A comprehensive security concept should be considered in many ways. Below are the possible weaknesses listed:

 

  • Larger address space
  • The main advantage of IPv6 on IPv4 is that it has a larger address space. IPv6 has an address length of 128 bits and ipv4 has 32 bits. Therefore, the address space is approximately 3.4 × 1038. This amount is approximately 4.8 billion × 1028 addresses are falling. In addition, the ipv4 address space is reserved as 14% of the ready address. While the numbers are too large, the intention of ipv6 address space designers is not to take the geographic satisfaction of available addresses.

 

  • Instead, their intent is to make long addresses easier to allocate addresses, to enable efficient routing stacks, and to allow certain addressing features. Classless inter-domain routing complexity in IPv4 As we know, Classless Inter-Domain Routing (CIDR) The standard size of the subnet in IPv6 is 264, which means that ipv4 is twice the size of the entire address space. In other words, the actual address space provision rate will be small in ipv6, but the network management and routing efficiency has been improved with large subnet space.

 

  • IPv6 requires a great deal of effort. Renewing an existing network for a new link provider with a different redirection requires a great deal of effort. With IPv6, the entire network will be advertised as a prefix change, and the host will be given a host number. Network identifier (at least meaningful 64 bits ) Are configured independently of each other by the host.

 

  • On a network, multiple destinations are multicast,
  • In IPv4, this is a common implementation, but it is optional. In IPv6 it is part of the basic definition. IPv6 multicast addressing shares common protocols and common features with ipv4 multicast, but ipv6 IPv6 does not require traditional IP broadcast implementation. A packet is sent to all connected hosts (internete connected computers) that use a specific broad-cast address. ) And therefore does not define the broadcast address. In ipv6, the same result as the broadcast is obtained by sending a packet to the link-local node (the connected machine-host). The ipv4 broadcast address matches the address 224.0.0.1 in ipv6 Ff02 :: 1 is the link-local multicast address. IPv6 provides a new multicast implementation that includes meeting with the point addresses within a multicast group address.

 

  • This facilitates the realization of inter-domain solutions. Achieving a globally routable multicast group assignment in IPv4 is very difficult and the implementation of the inter-domain solution is very mysterious. At least 64 bit forwarding prefix for ipv6 Unicast address assignments by the local internet registry produce the same result as the smallest subnet size in ipv6. With such an assignment, the unicast address prefix is ​​added to the ipv6 multicast Address format. Thus, each user of the ipv6 subnet can be adapted to globally routed source-specific multicast groups for automatically multicast applications

 

  • Network layer security
  • Internet protocol security (IPSec) was originally developed for ipv6. However, in the first ipv4, it found wide area usage. IPSec is a mandatory description of basic ipv6 protocol compliance, but has since come to be optional.
  • Simplified operation by routers

 

  • Packet headers and packet progression processes have been simplified in IPv6. Packet handling by routers is generally more efficient, although IPv6 packet headers are at least twice the size of ipv4 packet headers. For this reason, the end-to-end principle of Internet design has been developed.

 

  • Specifically:
  • The packet header in ipv6 is simpler to use in ipv4, because the selected header is used to distinguish advanced areas from infrequently used ones.
  • Ipv6 routers do not perform fragmentation. IPv6 machines (ipv6-configured network-connected computers) run path MTU discovery, or

 

  • They use a larger MTU than 1280 octets, which is the default MTU size of ipv6 to send packets or send packets. IPv6 headers are not checked by checksum. It is assumed that protection is secured by both link-layer and upper layer (TCP, UDP) error detection.

 

  • UDP / IPv4 can have a value of 0 if there is no checksum control, and ipv6 UDP needs its own checksum control, so ipv6 routers do not need to recalculate their header fields (like Time to Live (TTL) or hop count) . This enhancement can allow routers to perform checksum calculation using the hardware indicated in the connection speed, but there are still divergences for software-based routers.

 

  • The IPv4 TTL field is a renaming of the hop limit to indicate whether there is more waiting to calculate the time of the packet sent in the queue.

 

  • IPv6 in the Domain Name System (DNS)
  • In the Domain Name System, the machine names are matched to the IPv6 addresses by the AAAA resource records, called the 4-A registers. For the solution, the IETF has allocated the ip6.arpa field. This field is divided into 4 hexadecimal digits of the 4 bit units of the namespace IPv6 address. Method is defined in RFC 3596

 

  • On mobile communication
  • The mobile ipv6 triangular routing problem (mobile ip) is similar to mobile ipv4, and the packets sent from the corresponding host to the mobile host are first sent to the mobile hotsun home agent and then to the mobile host by looking at the home agent in the current location. The packets sent from the mobile host are not obtained with this method but are instead sent directly to their destination.

 

  • Expandability Options
  • The IPv6 packet header has a fixed size (40 octets).

 

  • After the IPv6 header, additional extensions are added as headers, whose size is limited to just the size of an entire package. The extension mechanism allows the protocol to be extensible, which allows future quality of service, security, transport, and many other features to be done without modifying the underlying protocol.

 

  • IPv6 transition preparation
  • Compatibility with the IPv6 network is primarily a matter of software or firmware. However, it is likely that some of the older equipment that can be upgraded in principle is replaced. The American Registry for Internet Numbers (ARIN) recommended that all Internet servers be served only to IPv6 clients as of January 2012. If the sites do not use IPv4 resources, they will only be accessible via NAT64 (Network Address Translation).

 

  • Privacy
  • Like ipv4, ipv6 supports unique global ip addresses that each device can potentially track. The design of IPv6 has been re-influenced by the end-to-end network design principles originally designed during early development of the Internet.
  • In this approach, each device on the network has a unique adrese that can be accessed directly from any location on the internet.
  • The effort required to provide the appropriate address space is provided by Network-address-translation (NAT), but the topologies in network address spaces, hosts and ipv4 have been disrupted. When address autoconfiguration is used, the hardware address (MAC address) The address is made unique by assuming the user’s online activities and the type of equipment for unique management.

 

  • Address auto configuration is not required for IPv6 hosts. With it, addresses are still not MAC address-based. Incoming networks are globally unique by NAT in private networks. The privacy extension for IPv6 defines secret addresses. When the privacy extension is activated, the operating system randomly generates an ip address with the network prefix assigned by generating the random host identifier.
  • These temporary addresses are used to communicate with remote hosts instead of traceable static ip addresses. The use of forwarding addresses makes it difficult to accurately track the user’s internet activity by scanning the activity flow for a single IPv6 address.
  • By default, the privacy extension is activated in Windows, Mac OS X (since version 10.7), and iOS (since version 4.3).

 

  • In some Linux distributions, the privacy extension is also active. Privacy extensions do not protect from monitoring user activity. Privacy extensions do not protect user activity monitoring if only one or two hosts use the given network prefix, and activity viewers keep this information. In this scene, the network is a unique identifier for front-end monitoring.

 

  • Network prefix monitoring is less conservative if the user’s ISP assignments are made by DHCP giving the dynamic network prefix.
(IPv6) Internet Protocol Version 6
Author: wik Date: 8:57 pm
Technology


Wik's Random Content