Module encapsulation 

CCSDS Encapsulation Packet Protocol (CCSDS 133.1-B-3). CCSDS Encapsulation Packet Protocol (CCSDS 133.1-B-3)

Encapsulation Packets provide a mechanism to carry non-CCSDS protocol data (e.g., IP datagrams) over CCSDS space links. They share the same Packet Version Number (PVN = 7, binary ‘111’) space as Space Packets (PVN = 0) but use a different header format.

Header Layout

┌──────────────────────────────────────────────────────┐
│ Packet Version Number (3 bits) = '111'               │
│ Protocol ID (4 bits)                                 │
│ Length of Length (2 bits)                             │
│ User Defined Field (4 bits)                          │
│ Protocol ID Extension (4 bits)                       │
│ CCSDS-defined field (1 bit)                          │
│ Packet Length (variable: 0, 1, 2, or 4 bytes)        │
└──────────────────────────────────────────────────────┘

The first two bytes are always present. The Packet Length field is 0-4 bytes depending on the Length of Length field.

Modules

bitmask

Bitmasks for the 16-bit encapsulation header.

Structs

EncapsulationHeader

The 2-byte mandatory portion of an Encapsulation Packet header.

Enums

Error

Errors for Encapsulation Packet operations.

ProtocolId

Well-known Protocol ID values (CCSDS 133.1-B-3, Table 4-1).

Constants

ENCAP_PVN

Encapsulation Packet Version Number (binary ‘111’ = 7).

Functions

read_packet_length

Reads the variable-length packet length from the bytes following the 2-byte mandatory header.

write_packet_length

Writes the variable-length packet length after the mandatory header.