Comment 6 for bug 1708316

network names are definitely not unique in neutron and I don't think it would be tenable to make them that way. Ignoring the backward-compatibility, it would make the acceptable name field values for a given tenant completely unpredictable because they can't see all of the names that are in use.

Even if we scoped uniqueness to (network tenant_id, network name), it would still result in cases where just the name collides when you have networks shared to a tenant either globally or via an RBAC entry.

I think the Nova API is going to have to change to key based on network IDs instead of names or one of the other solutions.