3 - ES-IS CLNS - End System to Intermediate System / ISO 9542

CLNS ES-IS (Fixed Part) PCI

Network-Layer Protocol ID (1 Byte)

Length Indicator (1 Byte) (ISO 9542)

Version / PID Extension (1 Byte)

Type (5 Bits)

Holding Time (2 Bytes)

Checksum (2 Bytes)

Address Part (n Bytes)

Options (n Bytes)