File System Driver or Filter Driver ?

I need to write a device driver that reflects as a network share some data
(and metadata) that exists in another media:

simple Client A will access server B.
Server B will export a share (CIFS/SMB share). The share should reflect the
content in server C which has a media that cannot be accessed by simple
client A.

Should I write a File System Driver or a Filter Driver for server B ?
What are the considerations ?