Introduction to IPv6

IPv4 has been around for quite a while now and up until recently it has worked fine. But with the address capacity limit of IPv4, new technology is needed. IPv4 has only a capacity of 4 billion addresses, and the introduction of handheld terminals and mobile phones with access to the internet are going to need more addresses than this.

IPv6 is not a new protocol, its ten years old but was released 6 years ago. It has many more addresses than IPv4, I don’t have the exact number but I’ve heard there are several hundred addresses for every square meter of the earths surface.

Even though IPv6 has a capacity of more addresses than IPv4, it’s actually smaller in space, about half. Here are the headers for both protocols:

IPv4:
Ver, IHL, ToS, Total Length
Identifier, Flags, Fragment Offset
TTL, Protocol, Cheksum
Source Address
Dest. Address
Options

IPv6:
Ver, Traffic Class, Flow Label
Payload Length, Next Header, Hop Limit
Source Address
Dest. Address

Details about the headers can be found here:
Short version
Long version

IPv6 has functionality that supports modern communication. One of the features is the possibility to prioritize data. This is very useful with broadband-services such as streaming of video and audio, wich is sensitive to slow connections. By giving this data higher priority it will be routed faster than e-mail and other internet-traffic on the network. This feature is also very useful for telephone services on the internet (VoIP, Voice over IP). This service is very sensitive to lost packages, as speech will become very unclear with just a little information lost.

The introduction of IPv6 is taking quite some time, because it’s not compatible with IPv4. You can’t just put an IPv6 router into an IPv4 network. Workarounds have to be created, here are two possibilities: 1. If an IPv6 router wants to gain access to a IPv4 network, it has to create a IPv4 wrapping around it’s packets. When another IPv6 router receives the IPv4 packet, it has to remove the wrapping. 2. Header translation, a way to translate an IPv6 packet to IPv4 and back again.

Ipv6 has built-in security. Perhaps this is going to compete with SSL. Her is a link on the issue.

Would you happen to know if the routers and other network devices will become kinda 'obsolete' once it changes?
Do you know when it is going to change? Apparently, Novell has some work already done and I would not like to be caught by the wave....

Thanks

Well, replacing IPv4 with IPv6 wont happen overnight. But sometime in the near future IPv4 will become obsolete. I suppose in a few years time, depending on the mobile-phone market. I guess there's some overhead involved with translating from one protocol to the other, so it's better to replace all the routers as fast as possible. Maybe we're just looking at a software upgrade, that I don't know.

As far as I've heard the process of replacing IPv4 with IPv6 is somewhat difficult. Metaphores like "replacing the engine of a plane while in mid-air" and the like is often mentioned. But there's some heavy resarch on this right now. I suppose the mobil-phone giants like Nokia, Ericsson and Motorola are spending quite a lot of resources, because their terminals(mobile phones) need the new protocol.

sometimes these coexist on the same piece of equipment on the same network right now. On some systems ipv4 and ipv6 are running. It is likely that the hardware corps will justify all these upgrades like they did in 2000.

No Doubt.... IPv6 is going to take years before it gets widely adopted.. But this is for the good...as its going to give technology a better chance to mature further and let admins and developers get a finer viewpoint of the required upgradation details ....

May the voyage be smooth.....

Its already taken years, it was orginally thought up in the early 90's...

for more indepth info check one of the leading websites on this sort of thing - http://www.cs-ipv6.lancs.ac.uk/

i2c