| CltpTag | Marker for a connectionless transport protocol tag in IEC 61850-90-5 data frames. |
| DummyKey | Temporary key used by IEC 61850-90-5 draft implementations. |
| KeySize | Size of keys. |
| MaximumAnalogValues | Absolute maximum number of possible analog values that could fit into a data frame. |
| MaximumDataLength | Absolute maximum data length (in bytes) that could fit into any frame. |
| MaximumDigitalValues | Absolute maximum number of possible digital values that could fit into a data frame. |
| MaximumExtendedDataLength | Absolute maximum number of bytes of extended data that could fit into a command frame. |
| MaximumPhasorValues | Absolute maximum number of possible phasor values that could fit into a data frame. |
| SessionHeaderSize | Common session header size. |
| Timebase | Timebase used by IEC 61850-90-5 protocol implementation. |
| TimeQualityFlagsMask | Time quality flags mask. |