Once again it is time to analyze browser usage in the US for the last month. July saw the appearance of Firefox 3.5, which has replicated the pattern seen with Internet Explorer 8, where it supplants the previous version slowly and linearly as people get around to upgrading.

Can MSIE 8 overtake MSIE 7 in August? How much will Firefox 3.5 usage grow in August and will it replace FF 3.0 as the dominant version in the Firefox family?

As with previous analyses, Internet Explorer 6 retains its iron grip on the corporate, custom Web application market. The question is not when, but if, this browser will actually fade away. It is unlikely that Internet Explorer 6 will disappear until Windows 2000 and Windows XP percentages are in serious decline.

This points to a larger concern that organizations will have to face within the next 18 months: What do they do when the Windows 2000 lifecycle terminates in July 2010 and as Windows XP sees fewer updates moving toward lifecycle retirement in 2014? [See the Microsoft LifeCycle information here]

Hiding from the inevitable just makes changes that much more dramatic and difficult.

It is not likely that the patterns in the StatCounter data will change until the summer vacation season is over in the US, and students bring their shiny new computers online at the start of the school year.

Using the visitor trending data collected and shared by StatCounter, I have undertaken a general analysis of browser distribution by global region. These metrics are collected using the embedded tags that StatCounter customers embed on their site to collect visitor metrics for their own use.

US data shows that MSIE 7.0 is in a dominant position, with Firefox 3.0 in the 25% range of market share. This trend extends into the North American data, which is heavily influenced by the US trend.

MSIE 8.0, still reports a lower distribution than Firefox 2.0. This data is most likely based on the usage of MSIE 8.0 RC1 version, as MSIE 8.0 was only released in GA last week. It is highly probable that these stats will change in the very near future with the release of MSIE 8.0 to Windows Update.

In the EU, where fear and loathing of Microsoft runs deep and true, Firefox 3.0 is approaching parity with MSIE 7.0. Also, the perennially favoured native son Opera makes a very strong showing with their 9.6 release.

Asia is a Web designers nightmare, with MSIE 6.0 continuing to be the most reported browser. This is concerning, not simply for design reasons, but for web compliance reasons. Effectively Asia has throttled Web development to an old warhorse, but to such a degree that there must be some overriding advantage to using this browser.

As an example, the statistical comparison of four Asia nations is broken out below. We’ll start with Japan where MSIE 7.0 has a clear lead in the statistics.

However, when China (People’s Republic), India, and South Korea are added into the analysis, the pull towards MSIE 6.0 is massive.

This trend needs to be studied in greater detail in order to understand why MSIE 6.0 is so popular. Is it because of licensing? Continued use of Windows 2000? Compromised computers? The data doesn’t provide any clear or compelling reason for this trend.

Moving to Oceania shows a return to the trend of MSIE 7.0 being the predominant browser with Firefox in second place, with these two browsers showing a substantial lead over the remaining field.

South America sees MSIE 7.0 as having the largest market share, followed by MSIE 6.0 and Firefox 3.0. Effectively there are no other browsers with substantial market share at present.

These statistics show that the three most dominant browser platforms by market share are the two MSIE platforms followed by Firefox 3.0. This is likely to change with the MSIE 8.0 GA last week and its predicted release to the masses via Windows Update in the near future.

However, the release of MSIE 8.0 may not be as exponential as is predicted. Corporate IT policies, which have been slow to embrace MSIE 7.0, are likely not going to make a giant leap to MSIE 8.0 overnight. Adoption among the general population will also depend on the ability of existing Web applications to adapt to a more standards-compliant browser platform.

Noticeably absent from most of these statistics is Safari in a position to challenge the three leading browsers. This indicates that even hardcore Mac users continue to use Firefox as their primary Web application and browsing platform. StatCounter backs this up by indicating that within their data, 8.36% of visitors from the USA were on Macs, while 3.15% of visitors used Safari.

Trends to watch in the near future:

• New browser releases (Firefox 3.1, Safari 4.0) and their effect on browser distribution
• Uptake of MSIE 8.0 once it is released via Windows Update
• Browser distribution is Asia

This is a “re-print” of an article I had on Webperformance.org that I notice that a number of people search for.

The use of Round-Robin DNS for load-balancing has been around for a number of years. It is meant to serve as a way to have multiple hosts with different IP addresses represent the sam hostname. It is useful, but as dedicated load-balancing technology began to evolve, its use began to decrease, as it was not sensitive to the conditions that exist within a server-farm; it simply told clients which IP they should connect to, without any consideration of the condition of the server they were connecting to.

Recently, I have seen a few instances where companies have switched back to Round-Robin DNS without considering the pitfalls and limitations of this particular method of load-balancing. The most dangerous of these is the limitation, set out in RFC 1035, that a DNS message carried in UDP cannot exceed 512 bytes.

2.3.4. Size limits

Various objects and parameters in the DNS have size limits.  They are
listed below.  Some could be easily changed, others are more
fundamental.

labels          63 octets or less
names           255 octets or less
TTL             positive values of a signed 32 bit number.
UDP messages    512 octets or less

When a UDP DNS message exceeds 512 octets/bytes, the TRUNCATED bit is included in the response, indicating to the client/resolver that not all of the answers were returned, and they should re-query using a TCP DNS message.

It’s the final phrase of the previous paragraph that should set everyone’s ears a-twitter: the only thing that should be requested using TCP DNS messages are zone transfers between servers. If a someone who is not one of your authorized servers is attempting to connect using TCP to port 53 of your DNS server, they may be attempting to do an illegal zone transfer of your domain information.

As a result, TCP connections to port 53 are usually blocked inbound (and outbound, if you run an ISP and you assume your users are up to no good). So, guess what happens when the truncated DNS information is re-requested over TCP? Web performance is negatively affected by between 21 and 93 seconds.[1]

So, simply put, DNS information needs to be tightly managed and examined, to ensure that only the most appropriate information sent out when a DNS query arrives. Using Round-Robin DNS to load-balance more than 5 servers indicates that you should be examining other load-balancing schemes.

This looks good on paper — apparently the project plan ran to eleven pages — but they made one very serious technical faux pas: they deployed two of the authoritative name servers in the UK.

The DNS gurus in the audience are saying “So what?”. This is because when you set up 4 authoritative DNS servers correctly, the query is sent to all 4 simultaneously and the one with the fastest response time is used. This usually results from the following type of configuration:

		dns1.foobar.com		10.128.6.2
		dns2.foobar.com		10.128.17.2
		ns0.snafubar.com	172.16.12.2
		ns-ext.barfoo.net	10.250.32.128

The client this morning, however, had a very different type of configuration.

		dns.foobar.com		10.128.6.2
		dns.foobar.com		10.128.6.4
		dns.foobar.com		172.16.12.2
		dns.foobar.com		172.16.12.4

When the authority record is returned in this fashion, the results are easily understood. The host name is the same for all four IP addresses, so the querying name server does what it is supposed to do in these situations: resort to the Round-RObin algorithm. Instead of querying all four name servers simultaneously, the querying name server rotates through the authoritative names.

Depending on where the authoritative name servers are located, the DNS lookup time could vary wildly. In the case of the client this morning, 50% of the DNS lookups were being routed to the UK, regardless of where the querying name server was located.