1. The NSE that is associated with an NSVC cannot be removed.
2. The NSE that is associated with a local NSVL cannot be removed.
3. The NSE that is associated with a remote NSVL cannot be removed.
4. The NSE that is associated with a PTP BVC cannot be removed.
5. The NSE that is associated with an SGSNNRINSEMAP cannot be removed.
6. The NSE that is associated with an SGSNNULLNRINSEMAP cannot be removed.