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Title text: SMS is just the worst, but I'm having trouble convincing people to adopt my preferred system, TLS IRC with a local server and a patched DOSBox gateway running in my mobile browser.

Explanation

This explanation may be incomplete or incorrect: Created by A VAGUELY MODERN SMS. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.



Messaging systems suffer from the network effect, as in order to communicate, both parties need to be using the same system. Though relatively ancient by modern standards, SMS is supported by almost every mobile device (unless you're using a kosher mobile phone or still on a DynaTAC) that has a phone number attached, which means if you want to send a message to someone, but aren't sure if you have a messaging protocol in common, you can be sure at least they have SMS.

The comic mentions many other communication systems, which offer various advantages in either security (end to end encryption) and or a bunch of general improvements filed under the label "vaguely modern", such as longer character limits and the ability to share media such as images in-service.

The messaging systems are shown in a Venn Diagram, with the categories corresponding to these three advantages. The intersections between the categories are very minimal: there are a few systems that have both E2E encryption and are modern, but no intersections with "supported by everyone", and SMS is the only system in that category. So when choosing a method of communication, you're usually faced with a compromise.

The title text proposes an alternative, absurd mingling of technologies in the vein of 1636: XKCD Stack. IRC is Internet Relay Chat, a similarly antiquated messaging service that may also never die, as suggested in 1782: Team Chat. DOSBox is an emulator that recreates the operating environment of MS-DOS; part of the absurdity is that DOSBox is intended almost solely for video games.

Various other comics have referenced the issue of chat services, including 1810: Chat Systems, 1254: Preferred Chat System, and 1782: Team Chat.

Vaguely Modern

Slack

Slack is a workplace messaging service that offers the ability for administrators to create channels in order to organize the discussion. It is asynchronous, which means that conversations can occur out of time, hours apart from each other. It also keeps track of every message, and everything in a public channel stays there forever for everyone to see. It is not encrypted and has been moving towards being less privacy-focused for end-users over the years as corporate demand for employee surveillance has prompted the company to offer ever more invasive services to administrators. Overall, it is a popular service with some large companies and non-profit organisations but does not yet have universal adoption.

Facebook Messenger

Facebook Messenger is Facebook's messaging app for phones, but not everyone has a Facebook account, or uses Facebook regularly.

Hangouts

Google Hangouts is a messaging service that can be accessed through the online Gmail client, as a separate web page and a standalone app for the phone. Theoretically, that means everybody has access to it, but modern usage patterns mean that most people do not use the attached web client and don't bother downloading the app. It allows users to upload significantly degraded images, links, and other media along with text with a copy-paste.

Discord

Discord is a communications program that offers both direct messages and "servers", membership groups with a variety of voice and text channels. Discord was initially designed to serve the needs of online gaming communities, but is now used by many other groups.

Various DMs

A DM (direct message) is a private message between two or more users. The term DM originated from Twitter, but is now broadly applied to any user-to-user messaging feature within a larger service.

Vaguely Modern & E2E Encrypted

Signal

Signal is an encrypted messaging service, popular among protesters and hackers who wish to remain anonymous. Signal allows for highly secure messaging and for messages to be deleted after a period of time.

iMessage

iMessage is the instant messaging service for Apple devices. iMessage features end-to-end encryption; however, it only works between Apple devices, so users of Android devices are not able to receive or send messages through iMessage.

WhatsApp

WhatsApp is a messaging service owned by Facebook. It is popular in multiple countries, namely Latin America and India.

E2E Encrypted

End-to-end encryption is another messaging system where only the communicating users can read the messages posted. In principle, it prevents potential eavesdroppers – including telecom providers, internet providers, and even the provider of the communication service – from being able to access the cryptographic keys needed to decrypt the conversation.

PGP Email

PGP (short for "Pretty Good Privacy") is an encryption protocol for privacy and authentication developed in 1991. PGP can be used for signing, encrypting, and decrypting data. It is used to ensure the validity of the nature of the sender of the message (ie. to make sure you got the email from the sender and not from someone else pretending to be someone else with malicious intent). PGP was also featured in 1181: PGP.

Various Obscure Projects

Randall is probably referring to the multitude of projects similar to those listed here that had end-to-end encryption but never went far.

Skype I Think

Skype is a video conferencing service owned by Microsoft released in 2003; thus Randall does not consider Skype "modern". He is unsure if Skype is end-to-end encrypted or not. Skype used to be E2E encrypted, but that was changed and now it does not have E2E encryption.

Jabber + TLS

Jabber.org (based on XMPP) is a communications protocol based on XML that was developed in 1999. The Jabber protocol could be used with Transport Layer Security (TLS) to have a secure communications service.

Supported By Everyone

SMS

SMS (short for Short Message Service) is a text-messaging service formally defined in the GSM standard in 1985 and first used in 1992. It limits messages to 160 characters, text-only. SMS has been extended by MMS (first used in 2002), which allows for "multimedia", including short videos, images and audio. MMS is also supported by most modern phones, but does not have any security features and is less powerful and less reliable than other messaging apps, making it less modern.

Transcript

A Venn Diagram is shown, framed in a box. It has three components:

Vaguely Modern, E2E Encrypted, Supported By Everyone



Items Solely in the Vaguely Modern category are:

Facebook Messenger, Hangouts, Discord, Various DMs



Items In both 'Vaguely Modern' and 'E2E Encrypted' categories are:

Signal, iMessage, Whatsapp



Items Solely in the E2E Encrypted category are:

PGP Email, Various Obscure Projects, Skype I think, Jabber + TLS



Items Solely in the 'Supported By Everyone' category is:

SMS

All other categories are empty.

[Caption below the comic]: Why SMS refuses to die



