Basics of IPv6
See about:
- Needs- Classes and Conversions
- Capabilities
- Address Composition
- Protocols
- Platform
and finally, the Bibliography.
Needs
Beginning in 1994, things on the internet started to get a little complicated. At that time, there were not enough IP addresses to serve large companies, which had several computers, and until then, there was no other more practical method, than putting them each with their IP address on the Internet, although it is not so frequently used, the need for more addresses was already noticed at this time. After that, methods like NAT ( networking address translation ) were created, which translates an Internet IP address into a local IP address, making the Internet network work locally for several computers using a single IP address.
In the past, people did not spend more than 2 to 3 hours connected to the Internet, so an alternative to reducing IP numbers (which were already getting restricted) was the use of dynamic IP addresses. This partially solved a major problem, which ended up generating profits for Internet providers, since it was possible to put more customers online, while other customers have their computers turned off, or without Internet activity (dial-up connections, the user barely used 1 hour of the day on average). However, things have changed, advanced, and more network devices like routers, NAT, servers, print servers, home remote control, among others.and others, work as if they were a computer on the Internet, and then they need an IP address for it, just like with cell phones, which now with the fashion of 3G, 4G and 10G in some countries, have taken over the Internet exhausting the last available IP addresses, apart from the time connected, before the user barely spent 3 hours connected to the Internet, but nowadays, with mobile devices, this has increased to almost 10 hours daily.
Before, people accessed the Internet, perhaps only in the service, and some in their own home. Currently, people connect at home, at the service, in shopping malls, walking the streets, on the move, while waiting for a bus, subway, sometimes in a simple MSN system (which Vivo offers to customers for R $ 5.00 / monthly approximately) to a Blackberry Curve from which the executive responds to emails every 5 minutes, and which are extremely important for the information of the company he works for. Today, deals are closed by e-mail, I myself have some products that I sell on a sales website, and the customers, from whom I buy my products, almost 90%, are customers I don't even know, and I never heard the voice of them, contact only by email, and in the nearest, only post offices.
With so many devices online, more people with more time online, carrying out the most diverse business transactions, email, entertainment, instant messaging, social networking sites, online shopping, online sales, has come to an end the number of IP addresses provided by version 4 of the Internet protocol.
The mobile terminal company OI, to try to minimize the problems of lack of IP address, all of its customers access the internet through a local network of the type WAN (local of long distance), of which it connects with its server of Internet to Internet, that is, all customers have only one IP address on the Internet. As most cell phones do not require open ports to receive data directly from the Internet, NAT does its job by being more than a guardian, since it works as a firewall, however, limiting users to access download sites (which lock the IP address to the every 24 hours per download) and / or file sharing services on adverse networks known as P2P (People To People).
The new version of the internet protocol, version 6, brings the advantages expected by the current nonexistent features of version 4.
Classes
In the new IPv6 standard, there are no classes defined as in the IPv4 standard, such as classes of type A, B, C, anyway, but there are other types of nomenclatures that should be highlighted. Obviously, since IPv6 encompasses all IPv4 addresses in a zero-started array, it can apply to the same class as IPv4, but officially, for IPv6 standard addresses, there are no defined classes.
The same definitions as for IPv4, are valid for IPv6. As described in the documentation, in the same way that it does not affect the security of the systems because IPv6 is very similar to its predecessor, in addition to being fully compatible, we have some specific classes of the new standard.
There is, instead of the previous standard that were divided into two types of class, Unicast and Multicast, there is another one called Anycast, which identifies network interfaces that belong to different nodes in the network. An anycast packet is sent only to one network interface, even if it is on different nodes and / or networks.
For compatibility with the previous standard, there are some important notes to follow:
:: / 96 | The zeros identify that the address is compatible with the previous IPv4 standard. |
:: 1/128 | Loopback address |
2001: db8 :: / 32 | Address used for example only, documents use this prefix (preferably) to assume that this address is an example. It should not be used, if used, routers will understand that it is just an example address for some type of test, and may discard the packet if there is too much traffic on the network, knowing that it is not an important packet for transit. |
fec0 :: / 10 | This is a local website address. This prefix identifies that this address is valid only within the organization. However, it has not been approved as an official standard by the RFC standard. |
ff00 :: / 8 | This prefix informs that the network is of the Multicast type, and any address with this prefix is understood to be a Multicast address. |
fe80 :: / 10 | Physical private local network address. It is not valid on the internet. |
Prefix 2001 | IP standard currently valid on the Internet. First, the prefix 2000 is used as the default. |
Multicast: It is sent to several network interfaces at the same time, as long as the address is in the range of ff00 :: to ff00 :: FF. (ff00 :: / 8).
Conversion of IPv4 Address to IPv6
Within IPv6, there is a conversion to hexadecimal format. Example:
0000: 0000: 0000: 0000: 0000: 0000: XXXX: XXXX.
Where there is an X, this is where the IPv4 address is allocated in the hexadecimal pattern, and for this reason, for IPv4 the mask :: / 32 is used. See the example below:
Capabilities
The capacity of IPv6 is unquestionable, it has in its total range, all IPv4 addresses for compatibility, in only a very small range.
There are eight groups with 16 bits each. In each group, it is possible to allocate 65536 computers, that is, before it was necessary 2 groups to allocate this number of computers, now in just 1 group a much larger quantity can be used.
See the table below with the number of hexadecimal digits used and the number of maximum network devices in the IPv6 topology, assuming the exclusion of IPv4 and reserved addresses, such as local network and / or other definitions:
IPv6 slot | Number of networked devices |
:: 0000 to :: FFFF | 65,536 |
:: 0000 to :: FFFF: FFFF | 4,297,967,296 |
:: 0000 to :: FFFF: FFFF: FFFF | 281,474,976,710,656 |
:: 0000 to :: FFFF: FFFF: FFFF: FFFF | 18,446,744,073,709,551,616 |
:: 0000 to :: FFFF: FFFF: FFFF: FFFF: FFFF | 1,208,925,819,614,629,174,706,176 |
:: 0000 to :: FFFF: FFFF: FFFF: FFFF: FFFF: FFFF | 79.228.162.514.264.337.593.543.950.336 |
Whole Ranjo (in scientific notation) | 3.4028236692093846346337460743177e + 38 |
For creating subnet-type networks, the network mask pattern is used by placing a “/” at the end of the address.
Example:
fe80: 3c6e: 3e6a: 3e90 :: / 128
This address informs that, each group from right to left, are the number of available hosts, and that the four groups from left to right, mean the identification of the network.
I believe that seeing this model above, it is clear how the network mask nomenclature works in the IPv6 standard, since typing ffff: ffff: ffff: ffff: 0: 0: 0: 0 would be out of place for this standard.
Each group has 16 bits, so for each group, add the ones used for the hosts, from right to left. By default, the default is to use up to 64 bits for hosts, which is enough.
Address Composition
IPv6, being a protocol developed to be fully compatible with the previous version, it encompasses all IPv4 addresses in its current range.
It consists of 8 groups of 16 bits (4 hexadecimal digits) separated by colons, that is:
To simplify writing, zeros written from left to right, can be supplied, as well as a conventional number that we know, that is, it is not mandatory to keep the four digits for the address in the IPv6 standard (as it also happens in IPv4, where you can write the number 5.3.10.3 instead of 005.003.010.003). The example would look like this:
To summarize further, there is another method, the summary of continuous zero blocks. By placing a colon in any part of the address, it is possible to supply the number of zeros. Look:
Note: You can only use “::” to inform that the address consists only of zeros.
For local networks, it starts with "FE8", see the example:
For multicast networks, the prefix "FF" is used. For IPv4 based addresses, on the basis, we take the IP address: 100.5.3.23. In IPv6, the equivalent is:
:: 100.5.3.23.
(IPv6 standard in a summarized standard that is easy to understand, points like IPv4 are used, but the value is converted to IPv6 within hexadecimal codes and with two points, in only two groups, namely the last two, considering from right to right) left, with 32-bit mask).
Protocols
ICMPv6
The new standard of the protocol, unites in only a single system, the old ICMP, ARP (Address Resolution Protocol), and IGMP (Internet Group Membership Protocol version 3), in only one standard, subdivided into two classes of information:
- Error Messages
Errors such as: Destination not found, Time exceeded, Package too large, etc.
- Information Messages
Subdivided into 3 message type groups:
Ø Diagnostic messages
Ø Network Area Discovery Messages (neighbor)
Ø Multicast Group Management Messages
Below, the detail of how the ICMPv6 package is composed and formed.
Here is a small table of some ICMPv6 data codes that are used in information packets and / or error messages:
ICMPv6 code | description |
1 | Destination Unreachable (Destination not available / found) |
two | Packet Too Big |
3 | Time Exceeded |
128 | Echo Request (Echo Request) |
129 | Echo Reply |
130 | Group Membership Query |
131 | Group Membership Report |
132 | Group Membershiop Reduction (Group Reduction) |
133 | Router Solicitation |
134 | Router Advertisement |
135 | Neighbor Solicitation (Area Request) |
136 | Neighbor Advertisement (Area notice) |
137 | Redirect |
138 | Router Renumbering |
Multiplataform. So much so that the IPv6 protocol has exclusive specifications for mobile devices, with specifications for handoff areas, reducing latency in the exchange of networks, whether they are WLAN, WCDMA, LAN, WAN, and other networks available in mobile interface networks.
Mobile IPv6
Mobile IPv6 is an IETF (Internet Engineering Task Force) standard on RFC 3775, which offers mobile interfaces and network nodes, improving speed in handoff areas, decreasing latency rates.
In the future, Mobile IPv6 can be used in networks such as WiMAX, WLAN and BWA, and others, maintaining the same IP address per mobile node.
IPv6 Handoff Areas (Mobile IPv6 implementation)
These are areas from which there is internet connectivity at two different points at the same time, such as on mobile devices, when there is an HSDPA 3G and Wireless signal at the same time, so the implementation of Mobile IPv6 improves the transfer from one to the other, totally transparent to the user, switching access points as quickly as possible, avoiding network bottlenecks at congested access points.
Adverse areas of IPv6 applications
Biometric sensors from the medical industry using IPv6
The sensors are used in patients, both in hospitals and in patients with critical levels such as old people or newly operated people.
These sensors created work natively with the new specification of IPv6, since it is possible to connect to available networks and maintain a single IP address for long years, without the need to change frequently, since there is a very large range for these addresses . The RFC is studying a case of using a specific range for network interfaces that take care of the patients' health. It is not yet known what is this range intended only for these types of devices.
Brief Description
IPv6, in addition to all these implementations, can be used on different types of platforms, health care, geographic control, as well as location devices, vehicles, in addition, of course, to computers and mobile cellular terminals.
Bibliography
IPv6 - Cisco Systems (visited: April 2010).
Cisco response to the US Department of Commerce IPv6 RFC ( Cisco response to the United States Department of Commerce on the IPv6 standards) http://www.ntia.doc.gov/ntiahome/ntiageneral/ipv6/comments/Cisco_IPv6_RFC_response.pdf
IPv6.com - ICMPv6 Technical Details and Advantages http://ipv6.com/articles/general/ICMPv6.htm
SubnetOnline.com - IPv4 to IPv6 converter http://www.subnetonline.com/pages/subnet-calculators/ipv4-to-ipv6-converter.php
Charpter 4 - Subnetting (IPv4 and IPv6) http://technet.microsoft.com/en-us/library/bb726997.aspx
Internet Engineering Task Force
http://www.ietf.org/
http://www.ietf.org/
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