Methods of connection to the network | Code | T1E1 | Description |
| CA1D | JM8 | 4-Wire Transmission (mini 6 pin) |
| CA1E | NA | Proprietary intra-exchange metallic channel |
| CA11A | RJ11C | Single Line Single Exchange Access Line |
| CA14A | RJ14C | Two Line (mini 6 pin) |
| CA15A | RJ15C | Waterproof jack |
| CA17A | RJ17C | Single Line hospital critical care (mini 6 pin) |
| CA25A | RJ25X | Three Line (mini 6 pin) |
| CA41A | RJ41S | Data DCE (mini 8 pin keyed) |
| CA45A | RJ45S | Data Programmed (mini 8 pin keyed) |
| CA48S | RJ48S | 4-wire Data line (mini 8 pin keyed) |
| NA | RJ61X | Four Line (mini 8 pin) |
| CA2DA | RJ2DX | DB50 Multiple line (PBX, KTS, or MUX) |
| CA2EA | RJ2EX | DB50 Multiple line (PBX, KTS, or MUX) |
| CA2FA | RJ2FX | DB50 Multiple line (PBX, KTS, or MUX) |
| CA2GA | RJ2GX | DB50 Multiple line (PBX, KTS, or MUX) |
| CA2HA | RJ2HX | DB50 Multiple line (PBX, KTS, or MUX) |
| CA21A | RJ21X | DB50 Multiple line (PBX, KTS, or MUX) |
| CA26A | RJ26X | DB50 Multiple line (PBX, KTS, or MUX) |
| CA27A | RJ27X | DB50 Multiple line (PBX, KTS, or MUX) |
| CA48T | RJ48T | DB50 Multiple line (PBX, KTS, or MUX) Data Route |
| CA81A | NA | DS-1 Digital Interface 1.544 Mbps |
| CA-A1 | RJ49C | ISDN 2 wire basic rate U reference point |
| CB-1D | NA | ISDN 4 wire basic rate S or T reference point |
| CA48C | RJ48C | DS1/ISDN Primary rate U reference point |
| CA48X | RJ48C | DS-1 Digital Interface 1.544 Mbps |
| CA48H | RJ48H | DS1/ISDN 50 pin multiple Primary rate U reference |
