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ExakTime gives users the FASTEST software downloads

More than 20,000 organizations rely on ExakTime for wireless time tracking and payroll solutions. However, new software releases, consisting of large 100-150MB files, to thousands of global customers, began to max out bandwidth from their South Bend, Ind.-based single location servers. ExakTime found themselves at high risk of customer churn due to slow downloads.

According to ExakTime’s Director of Software Development, Eric Renken, “We started doing our research and found some CDNs — most of which were outrageously priced. We needed performance, global coverage and speed…Doing it ourselves wasn’t economical.”

After undergoing a free trial, ExakTime chose CacheFly. Find out why.

Read the Case Study >

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We can purge your edge cache. . . Really Fast

Are you annoyed by waiting for things to happen?

Fed up with micro-managing web updates?

Wouldn’t you rather say, “make it so…” and move on to the next item in your to do list?


Introducing CacheFly’s new and improved Reverse Proxy purging system. We’ve now managed to update edge cache and measure it in milliseconds. Take a moment to watch our demo video, which demonstrates what we mean by ‘really fast’.

Whether you have 5 or 5 million objects, our instant purging system can handle it all.


Tech companies need to optimize software delivery and downloads: How CDNs can help

The halcyon days where software programs were delivered on compact discs and DVD media are gradually fading away—remember the floppy disk? However, despite this evolution, software is not actually getting any smaller. Embedded video, audio, and other media content are making the install size of most programs increase at an almost exponential rate.

Tech companies that provide software to customers are faced with a dilemma. They need to provide web-based delivery of their software programs, as well as any updates, while maintaining the file size for this software. Only the best content delivery networks (CDN) solve this dilemma.

Leveraging a CDN for fast web-based software delivery

Tech companies that offer online software to their customers need to ensure that clients are able to download the software in a timely manner. Slow or interrupted downloads are an easy way to make a customer unhappy, and you can be sure that word of these issues will spread quickly and discourage potential customers.

Leveraging a CDN for software delivery is a more practical way to improve download performance at a minimal cost than trying to make on-premise technology investments at your own company. Letting the experts in the field work their magic allows your firm to concentrate on writing great software.

What a CDN provides to software companies

In addition to 10 times the improved download times, CDNs also offer other tangible benefits to software providers. Unlimited scalability ensures that as your customer base grows, your download performance doesn’t suffer—no matter the size of your software. Security is handled easily using URL/referrer blocking as well as tight control to subscription-based content.

It is vital for tech companies to put their best foot forward when offering online downloads. Partnering with a quality CDN like CacheFly is a smart move to ensure your customer base remains happy and continues to grow.

Sign up for a free test drive and see why thousands of software providers trust CacheFly for faster downloads.

Photo credit: Wikimedia Commons

Measuring Throughput Performance: DNS vs. TCP Anycast Routing

Since 2002, when we pioneered the first TCP-anycast CDN, CacheFly has always used throughput and availability as the two metrics that drive us as a company.

Many CDNs rely on DNS-based routing methods; however, there are several differences between the two , which directly translates to throughput, the real indicator of a CDN’s performance as well as availability.  Since customers frequently ask us what the differences are between the technologies, here’s a quick overview discussing the benefits of TCP-anycast routing over DNS.


Cedexis measures highest average CDN throughput performance of a 100kb file in the U.S. in April, 2014.

Traditional DNS CDN

DNS-based routing is known as the ‘traditional’, or old-school way of doing global traffic management. DNS routing works by locating the customer’s DNS server and trying to make an informed decision on where the DNS server is located, and which CDN location is closest to that DNS server, and returns that IP address. This operated under the assumption that the physical location, as well as network topology, of the DNS server is a good approximation of both of those values for the actual client behind the DNS server. This is a big leap of faith* (especially in the age of services like OpenDNS and Google Public carrying a significant amount of the worlds DNS traffic).  As an example, a certain DSL providers maintains their DNS infrastructure in Atlanta, yet almost 60% of their subscribers are in Southern California – this results in 100% of the traffic behind those DNS servers being served from Atlanta. Not good.

* The edns-client-subnet extension (which CacheFly supports and uses with OpenDNS and Google, among others) ‘fixes’ this problem, however, the DNS based CDNs are struggling with the transition as their systems were designed to map nameservers to POPs, and the edns-client-subnet solution effectively requires them to now be able to map the entire routing table, which is a much bigger challenge to properly monitor performance/availability on a prefix-by-prefix basis in real-time.

More importantly, availability and failover is a large challenge when using a DNS solution, as the TTL of the response must be reached to change locations, and even then, some clients cache the first response and users have to actually restart their browser or client to get a new IP if a POP goes offline (assuming the CDN is even aware that it became unreachable). This can be mitigated by choosing a low TTL which many providers do; however, in turn, this delays performance as resolvers must frequently re-request the same DNS record, delaying the first connection for hostnames that should be in the resolvers cache.

TCP-Anycast CDN

Our TCP-anycast method leverages the best of both worlds – using both DNS and the actual core routing table of the Internet (BGP) to intelligently take client requests and serve from where the *client* is located on the Internet and lets the providers internal metrics find the topographically closest CDN server. This is a huge win for both performance and availability. With anycast, the actual IP address of endpoints never changes, which means we can use a high TTL to ensure a great end-user experience by letting resolvers cache a response. In the event of a provider outage, or if we need to take a POP offline for maintenance, traffic is seamlessly routed to the next best location, without requiring a browser restart, and with a rapid convergence time that’s simply not possible with DNS solutions.

Evaluating CDNs? Look for throughput.

Many of our customers use CacheFly to deliver larger files: videos, apps, games, software downloads; our throughput performance makes it a no brainer to use CacheFly.  What most people don’t realize, is throughput is *as important* for small object/web page delivery.  When researching web performance it’s easy to be convinced that response time or time-to-first-byte (TTFB) is the metric that you need to optimize for.  Those same articles and so-called experts will also tell you it’s extremely important to enable browser side caching, so that your clients don’t have to make a 304 request back to the CDN.

Here’s the thing.. measuring ‘response time’ or TTFB, is simply measuring the performance of 304 responses (headers without content).  These are the very requests you just eliminated with client-side browser caching!

So, if you’re not re-requesting content from the CDN, you want that first request (200 response) to complete as fast as possible.  That’s time-to-last byte (TTLB) – That’s throughput!


Start optimizing your static objects for time-to-last-byte and your site will load faster, period.


So..Why do people still focus on response time?

First, it’s still a huge factor in loading dynamic, server-generated content where the payload is small and the client spends most of the time waiting for the response to be generated.

However, for large, static content, the TTFB is a small percentage of the overall request – the client spends most of the time actually downloading the object.

Using latency or response time to estimate TTLB/throughput is a pretty good idea – when you don’t have a way to measure throughput.  And for most of the 2000’s, people didn’t have a way to measure this in the real world, so TTFB was as good a metric as any.

However, with the advent of RUM (real user monitoring) measurements from companies like New Relic of page render time, and companies like Cedexis and CloudHarmony actually measuring and reporting on real-world throughput, there’s no reason to use TTFB to makes guesses as to how fast the page will load, you can actually choose the fastest provider based on throughput.

Whether you’re looking for a CDN or are already using one, make sure you’re optimizing for throughput. I encourage you to take advantage of our 30-day test account and experience the CacheFly difference for yourself.

Cloud benchmarking provider finds CacheFly leads in global CDN throughput

CloudHarmony, a cloud performance benchmarking provider, recently announced results of its “Cloud Speedtest,” testing average latency and throughput performance of major CDN providers from 2011-2014. CloudHarmony’s data was entirely based on results of over 20M CDN tests from 5.1M unique users on 27,000 different ISPs, using Maxmind’s industry-leading GeoIP intelligence.

We’re pleased to say that the report found the CacheFly CDN to be #1 when it comes to overall throughput performance for both small and large file throughput. In the tables below, you’ll see CacheFly ranked highest among all major CDNs in 2014 for both small and large file throughput in North America, Europe, Asia and Oceania; small file throughput delivery in South America, and large file throughput delivery in Africa.

CDN Large File Throughput CacheFly

CDN Large File Throughput (2014)

CDN Large File Throughput Results (CloudHarmony, 2014)

CDN Small File Throughput Results (2014)

Seeing these results over such a long term study is extremely gratifying, since our entire platform has always been built around delivering our customers, the highest possible throughput. This report validates all the work our team does on a daily basis to optimize throughput. The amount and quality of the data that CloudHarmony has gathered is really impressive – they’re committed to offering the best cloud benchmarks and it shows.

Jason Read, founder of CloudHarmony, noted, “We created the cloud speedtest because we think the most important feature of a CDN is how fast it gets content to users. Measuring this is challenging, however, because there are thousands of ISPs each with unique and continually changing network performance capabilities. The speedtest allows us to summarize CDN performance regionally using data from millions of real users and thousands of ISPs globally.”

Read CloudHarmony’s full report, CDN Performance Summary 2011-2014