OSPF Network Mask?

Question:

I am configuring WS-C3560X-48T-S Price OSPF on our MPLS routers in order to advertise our internal networks out to BGP (via the redistribute command).  I am a bit confused on the proper syntax of the OSPF network command for our situation.  The normal setup is that the MPLS router has a link to the core router for that site via a /24 network.  That network is part of a /21 range for the entire site, so the networks would look something like this:

MPLS link to core: 192.168.1.0/24

Core networks: 192.168.1.0/24, 192.168.2.0/24, 192.168.3.0/24, etc.

Would the best option for  OSPF network statements be:

MPLS router: network 192.168.1.0 0.0.0.255

Core router: network 192.168.1.0 0.0.7.255

or

MPLS router: network 192.168.1.0 0.0.7.255

Core router: network 192.168.1.0 0.0.7.255

or

MPLS router: network 192.168.1.0 0.0.0.255

Core router: network 192.168.1.0 0.0.0.255, network 192.168.2.0 0.0.0.255, network 192.168.3.0

Answer:

I would enable OSPF just in the interfaces that are going to speak this protocol, for example WS-C3560X-48T-S :

net 192.168.1.1 0.0.0.0 area 0

net 192.168.2.1 0.0.0.0 area 0

net 192.168.3.1 0.0.0.0 area 0