What is the relation between VRC and LRC?

Answer 1

VRC is generally a parity check for each group of bits, whereas LCR is generally a parity check performed horizontally across a set number of groups of bits.

eg. assuming even parity, for the follow 2 packets 10001100 and 01111011 the VRC is 10 (first bit is 1 as 1st packet has and odd number of ones, second bit is 0 as second packet has an even number of ones)

For the same 2 packets, LCR:
packet1: 1 0 0 0 1 1 0 0
packet2: 0 1 1 1 1 0 1 1
LRC: 1 1 1 1 0 1 1 1