This is a cross-project effort, this is the part for VTN.

Both vtn and genius contain copies of AD-SAL classes, effectively forking removed AD-SAL. This means these components cannot inter-operate as they carry same concepts in different packages:

user@work : ~/odl/autorelease on master $ find . -name IPv4.java
./vtn/manager/api/src/main/java/org/opendaylight/vtn/manager/packet/IPv4.java
./genius/mdsalutil/mdsalutil-api/src/main/java/org/opendaylight/genius/mdsalutil/packet/IPv4.java

These classes should either be eliminated or be merged into a common repository, so they can be maintained in one place.