CHECKSUM CALCULATION
Computed based on 64-bit Words
Simple Arithmetic Register Sum of ALL Five Words including DATA
Starting Value of SUM = 0x0123456789ABCDEF
Starting Value of In-Memory CHECKSUM field = 0x0000
ENDIAN variations result in Multiple Possible "Correct" Values
Right-Most 16 bits of Arithmetic Sum stored as CHECKSUM
CHECKSUM does not change in transit because TTL or Hop-Limit Re-Purposed
ADDITIONAL DATA CHECKS
All Data is REPEATED as many times as possible filling 16 bytes
Data can be checked for errors in concert with CHECKSUM
Errors in the 4-bit DL (Data Length) Field can be Detected & Corrected
CHECKSUM errors can trigger Data Integrity Checks & Re-Construction
ZERO Synchronization
Deprecated Payload Length of 0X0000
CHECKSUM can be viewed as 32-bits with 0X0000
Other Fixed Values (i.e. 59) can also be used in CHECKSUM cross-check
USAGE in DHT KEY
CHECKSUM is used in the 480-bit DHT KEY in 320-bit Packet
CHECKSUM created by Sender or Originator reflects Sender ENDIAN
