The command message format used by russian central military commandment network is called Monolyth (rus. сигнал Монолит).
The name came from urgency level name. Urgency levels used in russian military radiotelephony are
- Monolyth(Монолит) - the most urgent message level, interrupts all other possible transmissions
- Air (Воздух) - came after Monolyth and interrupts all other messages except Momolyth level messages
- Rocket (Ракета) - cames after Monolyth and Air and interrupts all other except those two mentioned
- Airplane (самолет) - cames after Monolyth, Air and Rocket, interrupts regular messages
- Regular (обыкновенная) - cames after all previous categories
This is taken from standard russian military radiotelephony rules
The message content use generic standard as following:
callsign(s) xx xxx CodeWord xx xx xx xx
There is no description in public about the meaning of each part, but our monitoring give some thoughts about first two digit groups, which seems to be in connection with recipient. It is possible for example that they are coming from: xx - district number, xxx - some numbers from unit number (which is 5-digit number in Russia).
This theory can be seen for example in this PIP message addressed for 4 recipients:
ДЛЯ 5Ф7Щ 49ФГ ТУЗР 5Й7Щ 66 431 56 298 43 202 66 185 ОТЦЕПЩИК 98 69 21 67
As you can see, there are 4 recipient callsigns, followed by 4 2+3 digit groups and then comes the message itself.
The message content has been discussed a bit in russian forums and it is known that message CodeWord usually address some envelope with instructions, where last 4 2-digit groups is the message itself and can be decoded using given envelope.
МДЖБ 34 568 ГАШЕНИЕ 48 95 48 13 ЗИЗИФУС 98 36 19 35
There are also so called Zone Covering messages, their purpose is to fill up the air with some content without any real meaning. Their format follows monolyth format, but the message itself has no real meaning. In russian terminology they are called Зонально-Маскировочные сообщения or Зоны (zones).
Here is the old buzzer transmission site log journal page showing both monolyth (сигнализация Монолит) and zone covering (зона) messages