Editing 2224: Software Updates

{{comic
| number    = 2224
| date      = November 5, 2019
| title     = Software Updates
| image     = software_updates.png
| titletext = Everything is a cloud application; the ping times just vary a lot.
}}

==Explanation==
{{incomplete|Created by EXPLAINXKCD IS JUST SOFTWARE AS A SERVICE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

As time passes, upgrades to most products are inevitable, with software being no exception.

However, as many updates create multiple versions, support for all of them can become a bit of a hassle for the company that creates them, so old versions frequently become unsupported after some years, or in some cases even months, of their releases.

For users that prefer to stay on old editions because of unfavorable changes in the newer programs, this can mean that they are left unsupported, causing them to become more susceptible to hard to solve bugs, newly discovered security vulnerabilities, or incompatibilities with newer versions of operating system or other software.  Emulators or virtual machines are one way to keep such a program running as though it were in its native environment.

The punchline of the comic is the caption underneath the panel, "All software is software as a service". {{w|Software as a Service}} (SaaS) is a software licensing and delivery model in which software runs on the vendor's computers (servers), accessed by customers remotely. The software is said to run "in the cloud" as "cloud applications". Customers purchase subscription licenses. Since the only copy of the software is that which the vendor runs on their own computers, all customers use the one latest version of the software, which is upgraded whenever the vendor chooses to. If the vendor removes or changes a feature that the customer prefers, or introduces a bug, the customer has no ability to remain with an older version. A major benefit of SaaS is that the customer never has to do anything to upgrade to the latest version of the software to get fixes to newly discovered bugs or security vulnerabilities. A major disadvantage of SaaS is that the customer may lose some feature of the software that they depend on, or get impacted by a new bug that is introduced by an upgrade to the software, and has no ability to run the older version.

With traditionally marketed software that they purchase to run on their own computers, customers can choose not to upgrade. Vendors will stop providing support for their oldest versions, which can cause problems for those customers who do not upgrade when bugs or security vulnerabilities are discovered, or newer versions of operating systems require changes in the software. A customer may eventually be forced into the bind of having to upgrade just to be able to run the software, but then lose the feature in the software that they depend on.

Since vendors eventually stop supporting the older versions of software, and over time more problems may appear that make it more difficult to continue to run the unsupported versions, in a way all software has the same disadvantages that SaaS presents by forcing everyone to upgrade. In that sense "All software is Software as a Service".

The title text refers to a different aspect of cloud applications. Since they run "in the cloud" on remote computers, they are subject to the effects of network speed to the servers. The time for data to be sent to a server and a response to be received back is called the "ping time". 

Since a "cloud server" is just a computer, there is no fundamental difference between software running remotely and software running locally on a user's computer. The biggest difference is that software running locally will respond almost instantly to user input, whereas software running remotely may take longer to respond, since the data first needs to be sent over a network (the internet), processed, and then sent back to the user's computer. In addition, the chance of data loss (packet loss) may cause the response to be even slower, as data has to be re-sent, or often result in no response at all. Hence, in practice, this can have an enormous impact on the experience of using remote software vs software that runs locally (as anyone who has tried online gaming on a laggy server can attest). 

However, technically speaking, there is a nonzero time taken for the data to travel from the user's keyboard onto the computer, across the various circuitry, and back to the monitor. Hence there is a "ping" time even for a local computer (in fact, many "gaming" monitors advertise low input lag, in the order of 1-5 milliseconds, as a feature). Therefore, you could technically say that all applications are cloud applications, just that some (local computers) have very fast ping times whereas for others (servers on another continent) it may be quite slow. 

This ignores the fact that being a "cloud application" implies that it runs on a server in a remote location. The joke is like saying that everyone commutes to work - including those that "work from home" - but their commute times just vary a lot. For example, consider the "commute" from your bedroom to your home office.

==Transcript==
:[A graph with two axis. Over and right of the axis are two labeled arrows pointing along the two axis:]
:X-axis: Time 
:Y-axis: Software Version Number 

:[The graph consist of three lines. Two gray lines moves in upwards step from left to right. The upper line begins a bit up the Y-axis the bottom line begins somewhat down the X-axis. From there both lines move upwards in steps of different height. The distance between them stays on average about the same for the entire graph, but moves from bottom to top of the graph. Labeled arrows point to the top and the bottom gray line. The area between them is shaded light gray and has a gray label written in the middle. The third line is black. It begins from a dot just under the second step in the upper gray line. This line also makes steps, keeping close to the upper line, although it makes fewer step than that line. But a bit over halfway to the top, it stops stepping staying on the same level for the rest of the graph, thus  eventually it falls outside of the light gray area between the other two lines, where it had been until the bottom line steps above it. This black line is also labeled, with normal black text written beneath the first full step inside the gray area. Three other points on the black line is also labeled. The starting dot, a second dot just after the final step, under the next large step in the upper gray line, and finally at the end of the black line there are questions mark with an arrow beneath pointing right. The arrow has a label to the left.]
:Upper gray line: Newest Version
:Bottom gray line: Oldest Supported Version
:Light gray area: Support Zone
:Black line: My current version
:Start dot: First Install
:Second dot: An update finally breaks a feature I'm unwilling to lose
:End of black line: ??? 
:Arrow label: The Abyss

:[Caption below the chart]:
:All software is Software as a Service.

{{comic discussion}}

[[Category:Line graphs]]
[[Category:Timelines]]
[[Category:Programming]]