[zeromq-dev] Can I make a ROUTER ignore a client's ZMQ_IDENTITY?

[Tom Nakamura]

If a REQ socket sends a message to a ROUTER socket, the recipient gets
the message prefixed with an identity frame and an empty frame. The
client can make the ROUTER use a specific client-id by setting
ZMQ_IDENTITY. Is there a way to make the ROUTER ignore this? If I expose
a ROUTER socket to unknown/untrusted clients, then the router may get
multiple connections with the same identity by accident or malice
resulting in a denial of service.  Or am I missing something in the way
routers work?
Tom