SVL
    In Shared VLAN Learning, two or more VLANs are grouped to share common source address
        information in the MAC table. The common entry in the MAC table is identified by a Filter ID
        (FID). SVL is useful for configuration of more complex, asymmetrical cross-VLAN traffic
        patterns, like E-TREE (Rooted-Multipoint) and Multi-netted Server. The alternative VLAN
        learning mode is 
IVL (Independent VLAN Learning). The default VLAN learning mode is IVL.
        Not all switches support SVL.