IPv6 adoption continues to grow with Akamai Technologies observing a 2.1 per cent increase (from the third quarter of 2011) globally in the number of unique IPv4 addresses connecting to Akamai’s network, growing to over 628 million, in their most recent State of the Internet report.In the fourth quarter of 2011, over 628 million unique IPv4 addresses, from 236 countries/regions, connected to the Akamai Intelligent Platform – 2.1% more than in the third quarter of 2011, and nearly 13% more than in the fourth quarter of 2010. Although we see more than 600 million unique IPv4 addresses, Akamai believes that we see well over one billion Web users. This is because, in some cases, multiple individuals may be represented by a single IPv4 address (or a small number of IPv4 addresses), because they access the Web through a firewall or proxy server. Conversely, individual users can have multiple IPv4 addresses associated with them, due to their use of multiple connected devices.IPv4 exhaustion continues with the number of available IPv4 addresses continued to decline, as Regional Internet Registries (RIRs) allocated/assigned blocks of addresses to requesting organisations within their respective territories.The report notes austerity measures employed by APNIC as it reached its final /8 (16.8 million IPv4 addresses) block on 15 April leading to APNIC allocating the lowest volume of IPv4 addresses assigned during the fourth quarter. Of the other RIRs, AFRINIC’s IPv4 exhaustion proceeded slowly during the fourth quarter as well while LACNIC allocated/assigned over 2.5 million IPv4 addresses during the quarter, with over half a million allocated on November 7. In contrast, RIPE was significantly more active, assigning or allocating more than 200,000 IPv4 addresses on many days during the quarter, peaking at 883,968 IPv4 addresses on 1 December. However, in comparison, ARIN’s activity was much more subdued during the quarter.Recognising that IPv4 address space is a valuable commodity, the report notes bankrupt bookseller Borders announced a plan in December 2011 to sell 65,536 IPv4 addresses (a “/16″”) to Cerner, a healthcare software vendor for $786,432, or $12 per address. Akamai believes this was the second publicly announced sale of IPv4 space, after Nortel’s sale of $7.5 million worth of addresses to Microsoft in April.Projected exhaustion dates for the various registries range from August 2012 for RIPE to all the way out in October 2014 for AFRINIC.On IPv6 adoption, the report notes there were higher rates of growth seen during the second quarter of 2011, and commensurately lower growth rates seen in the third and fourth quarters that may be related to preparations for World IPv6 Day (8 June, 2011), organised by the Internet Society as a 24-hour “test flight” of IPv6 for real-world use under controlled conditions. Building on the success of this event, the Internet Society is coordinating World IPv6 Launch on June 6, 2012.The report examines a range of issues dealing with the internet. One is broadband adoption. The report found global average connection speed was 2.3 Mbps, and the global average peak connection speed remained 11.7 Mbps.At a country level, South Korea had the highest average connection speed at 17.5 Mbps, as well as the highest average peak connection speed, at 47.9 Mbps. At a city level, cities in South Korea and Japan continued to hold many of the top spots in the rankings of highest average and average peak connection speeds.Globally, high broadband (>5 Mbps) adoption declined slightly to 27 per cent in the fourth quarter, and South Korea continued to have the highest level of high broadband adoption, growing to 83 per cent. Global broadband (>2 Mbps) adoption remained at 66 per cent, with the Isle of Man having the highest level of broadband adoption, at 97 per cent. Global narrowband (<256 kbps) adoption continued to decline, losing a bit more than one percent quarter-over-quarter, but staying at 2.5 per cent.On mobile broadband and connectivity, the report observed overall fourth quarter attack traffic from known mobile networks increased slightly, with the top ten countries generating 78% of observed attacks. The list of top targeted ports remained mostly consistent with the third quarter -- Port 8080 (HTTP Alternate) replaced Port 4899 (Remote Administrator) among the top 10. Port 445 remained the target of an overwhelming majority of observed attacks as compared to other ports in the top 10.In the fourth quarter of 2011, average connection speeds on known mobile providers ranged from 5.2 Mbps down to 163 kbps. Average peak connection speeds during the quarter ranged from 23.4 Mbps to 1.6 Mbps. Looking at mobile content consumption, users on eight mobile providers consumed, on average, more than one gigabyte (1 GB) of content from Akamai per month, while users on an additional 75 mobile providers downloaded more than 100 MB of content from Akamai per month during the fourth quarter.More detailed information on the above and much more are available in Akamai Technologies’ State of the Internet report. A news release of the highlights is available from www.akamai.com/html/about/press/releases/2012/press_043012.html while a 50+ page report is available for download from www.akamai.com/stateoftheinternet.