I am not sure if you guys are familiar with this topic but it has been a concern since the internet began taking off back in the 80s. It is a common topic discussed among IT professionals like myself. IPv4 is the current and most widely used internet layer, but the problem is that IPv4 is 32 bit and provides for about 2^32 (around 4 billion supposedly) unique IP addresses. Well as you probably know, the internet is always growing at a fast rate and it is inevitable that we will eventually run out of IP addresses. This is very similar to ESNs used with CDMA mobile phones in the US. A unique ESN is assigned to every CDMA mobile phone and because of the limitations of 32 bit numbering, ESNs are running out. A new system has been adopted to replace ESNs since then. Most end-users probably don't even think about this, but the topic of IPv4 exhaustion has come up once again recently. This is because many networking companies and experts (such as Cisco) have estimated that we will actually run out of IP addresses sometime around late 2010 or during 2011. The most practical way around this is to switch to IPv6 which is 128 bit. This will allow for up to 2^128 IP addresses which is a massive improvement over IPv4. (That would give us enough unique IPs that we would technically no longer have to use NAT routers.) IPv6 is currently still not very widely in use but it is most likely that most ISPs will begin issuing IPv6 addresses in the near future. All networked devices will eventually need to convert fully to IPv6 or use an IPv6 to IPv4 gateway as the two systems are not directly compatible. Most software and hardware companies are claiming that this transition won't be too much of a hassle for the consumers because most hardware will be upgradeable to IPv6 with a firmware patch and most software will receive an update. Hopefully then we won't have to go out and buy new hardware. Most software and hardware being sold now is already IPv6-ready including all current major operating systems. I would like to add the IPv6 addresses are much more complex and are longer (due to its 128 bit nature) than IPv4 addresses. Here is an example of an IPv6 address 2001:0db8:85a3:08d3:1319:8a2e:0370:7334 Anyways, that's what I have to say about IPv6 right now. Its a pretty interesting thought that we have almost exhausted all of our current IP addresses. What do you guys think about this topic?