| Wert | Bedeutung | 
| AA | Circuit switching | 
| AB | SITA | 
| AC | ARINC | 
| AD | AT&T mailbox | 
| AE | Peripheral device | 
| AF | U.S. Defense Switched Network | 
| AG | U.S. federal telecommunications system | 
| AH | World Wide Web | 
| AI | International calling country code | 
| AJ | Alternate telephone | 
| AK | Videotex number | 
| AL | Cellular phone | 
| AM | International telephone direct line | 
| AN | O.F.T.P. (ODETTE File Transfer Protocol) | 
| AO | Uniform Resource Location (URL) | 
| AP | Very High Frequency (VHF) radio telephone | 
| AQ | X.400 address for mail text | 
| AR | AS1 address | 
| AS | AS2 address | 
| AT | AS3 address | 
| AU | File Transfer Protocol | 
| AV | Inmarsat call number | 
| AW | Radio communication call sign | 
| CA | Cable address | 
| EI | EDI transmission | 
| EM | Electronic mail | 
| EX | Extension | 
| F | X.400 address | 
| FT | File transfer access method | 
| FX | Telefax | 
| G | Pager | 
| GM | GEIS (General Electric Information Service) mailbox | 
| H | International telephone switchboard | 
| I | National telephone direct line | 
| IE | IBM information exchange | 
| IM | Internal mail | 
| J | National telephone switchboard | 
| MA | Mail | 
| PB | Postbox number | 
| PS | Packet switching | 
| SW | S.W.I.F.T. | 
| TE | Telephone | 
| TG | Telegraph | 
| TL | Telex | 
| TM | Telemail | 
| TT | Teletext | 
| TX | TWX |