ospf network definition for adding all interfaces / default route

What’s the difference?

router ospf 1

network 0.0.0.0 0.0.0.0 area 0

vs.

router ospf 1

network 0.0.0.0 255.255.255.255 area 0

Both add all existing interfaces into area 0 and all later added interfaces also. Both statements are valid.

For the default route it seems the same:

ip route 0.0.0.0 0.0.0.0 f1/1

vs.

ip route 0.0.0.0 255.255.255.255 f1/1

both work, sending traffic to the default gatewayf f1/1.

What IOS does not permit is a mixture for example.:

0.0.0.0 0.0.255.255

or

0.0.0.0 0.255.255.255

SW1(config)#ip route 0.0.0.0 0.0.255.255 f1/1
%Inconsistent address and mask

Both statements are the same. Since both have the same logical „AND“ing result for the host part, namely „0“.

0 0 0 0 0 0 0 0

1 1 1 1 1 1 1 1

———————-

0 0 0 0 0 0 0 0

vs.

0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0

———————-

0 0 0 0 0 0 0 0

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