Eventhough TCP checksums and Link CRC checks are robust, it is not entirely impossible that false positives can be generated on the verification of network packet data. This could lead to broken data in the database which cannot be detected.
Thus wire protocols are advised to implement application level data integrity checks such as CRC's to provide even greater redundancy.
CRC-32 implementation is trivial and with table lookups performance hits would be negligible.
By implementing a CRC32 into the header or footer of the wire protocol could provide even greater redundancy and stability to what already is a robust system.