Editing 1514: PermaCal

{{comic
| number    = 1514
| date      = April 20, 2015
| title     = PermaCal
| image = permacal.png
| titletext = The flood of PermaCalNTP leap-second notifications was bad enough, but when people started asking for millisecond resolution, the resulting DDOS brought down the internet.
}}

==Explanation==
This comic proposes a new calendar system, named PermaCal (a malamanteau of the words "permanent" and "calendar"). In it, the date stays constant. In order to accomplish that, as each day passes, it is interpreted as "drift", and a new PermaCal leap day (analogous to the {{w|February 29|leap day of the Gregorian calendar}}) is added to compensate.

In the comic, which was published on Monday April 20, 2015, Megan wonders why today would be the 19th, since Cueball said it was the 19th a day ago. [[Cueball]] interprets the news from Megan, that a day has passed, as "drift" in the date, and resolves to add another leap day to PermaCal so that his calendar will be correct. He is presumably becoming frustrated that he has to do this so often.

Leap days in the {{w|Gregorian calendar}} are days added to the end of {{w|February}} every year that is a multiple of 4, but not by 100, unless it's also a multiple of 400. The purpose is to synchronize the calendar with Earth's orbit without having a partial day each year. {{w|Leap second|Leap seconds}} are necessary because the earth rotation is not constant, but speeds up and slows down over time. The leap seconds account for the differences in the length of our 24 hour day and a solar day (the time taken for Earth to rotate once with respect to the sun), and are announced several months beforehand.

{{w|Network Time Protocol|NTP}} servers are used to keep local computer time from drifting. They also are used to announce {{w|Leap second|Leap seconds}}. In the context of this comic, leap seconds would refer to a different system in which there is a new leap second each second, so the time also stays constant, down to the resolution of one second. This would require something like setting the NTP leap second bit anew every second. The title text presumably refers to moving to a resolution of one millisecond via leap milliseconds. This would require at least 1000 updates being requested every second, using enormous network bandwidth and resulting in a Distributed {{w|Denial-of-service attack}} (DDoS) situation.

The comic relates to several DDoS problems due to {{w|NTP server misuse and abuse}} over the years.

Part of the humor stems from the problems that leap seconds are causing for some computers. [http://www.livescience.com/49370-leap-second-added-2015.html] The last leap second disrupted computers at big companies such as {{w|Reddit}}, {{w|LinkedIn}}, {{w|Gizmodo}} and {{w|FourSquare}}. {{w|Google}} first [http://googleblog.blogspot.com/2011/09/time-technology-and-leaping-seconds.html introduced a new approach of ''smearing'' the leap second], smoothly changing the reported time over an undisclosed number of hours around midnight UTC on December 31, 2008. The smooth shape of the adjustment is graphed at [http://stackoverflow.com/questions/11279992/math-behind-google-leap-second-smear-formula synchronization - Math behind Google leap second smear formula - Stack Overflow].

A new calendar was also proposed in comic [[1061: EST]].

==Transcript==
:[Megan and Cueball are in the panel. Cueball appears to be holding a phone, tapping.]
:Megan: What day is it?
:Cueball: Sunday the 19<sup>th</sup>.
:Megan: But you said it was the 19<sup>th</sup> yesterday.
:Cueball: It changed ''again''?  Crap, better add another leap day.
:[Caption below the panel:]
:My simplified calendar system assumes the date never changes, then corrects any drift via leap days.

==Trivia==
*The "H" in Megan's version of "19TH" is missing the upper part of the left bar, making it look like an mirrored "h". This must be unintended, since the H in "19TH" is written correctly when Cueball says it. Also only capital letters are used in the comics (except in special cases).

{{comic discussion}}
[[Category:Comics featuring Cueball‏]]
[[Category:Comics featuring Megan‏]]
[[Category:Time management]]
[[Category:Portmanteau]]
[[Category:Calendar]]