With mass communication comes mass annoyance. That bane of modern life – the overheard cellphone conversation – has now come to North Korea, prompting the authorities there to issue guidelines on how to use the newfangled devices.

"As mobile phones are being used increasingly in today's society, there has been a tendency among some people to neglect proper phone etiquette," some North Korean state journalists, taking a break from their usual stories about Kim Jong Un’s amazing feats, wrote recently in a piece titled "Language etiquette in phone conversations" published in a quarterly magazine on North Korean culture.

The piece, first reported by South Korea’s Yonhap news agency, stresses the importance of proper manners in mobile phone use – and how to deal with the advent of caller display.

"On mobile phones, unlike on landlines, conversations usually take place with knowledge of the other person. However, even in such cases, one must not neglect to introduce oneself or offer greetings," the magazine advises, according to Yonhap. For example, if someone doesn’t introduce themselves, a polite North Korean phone user would still confirm that it really is the phone owner who’s on the other end: "Hello? Is it you, comrade Yeong-cheol?"

And forget about those mega-decibel “I’m on the train!” answers. "Speaking loudly or arguing over the phone in public places where many people are gathered is thoughtless and impolite behavior," North Korea’s answer to Miss Manners advises.

Cellphones are a relatively new piece of technology in North Korea, where Kim Jong Un’s regime keeps control of the populace by severely restricting their access to information. There’s no Internet service. Outside newspapers? Forget it. DVDs of foreign films? Go for it, if you like gulags.

Cellphones were banned until a few years ago, when North Korea allowed the Egyptian phone operator Orascom Telecom to start a cell service called “Koryolink.” About 2.5 million people – coincidentally the same number of people who live in Pyongyang, home of the most loyal political class – are thought to subscribe to the service. That’s 10 percent of the population. North Korea even makes its own cellphones now – or rather, it puts its labels on Chinese phones. Basic phones are the most common, but technophiles can get an Arirang smartphone – but no 3G, of course.

If you want real phone access in North Korea, you need a Chinese subscription and to be on the border, in range of Chinese cell towers. Yep, North Korea is so restricted that even China seems like an information paradise.