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Whether we usual use dot-decimal notation to represent network or IP by opposite mask?

10.10.10.0 0.0.0.255 # a network
10.10.10.0 255.255.255.0  # a IP

Update

if we represent a network, we can use 10.10.10.0/24, but how can we represent a IP address of 10.10.10.0 with mask? Is it not 10.10.10.0/24 too?
I also sometimes find the 10.10.10.0 0.0.0.255 can represent a network, what's the difference.

Update-02

Some friend says like the 192.168.2.1/32 can not stand for the networks, but in the route, there obviously regard this as a subnet.

     192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C       192.168.1.0/24 is directly connected, GigabitEthernet0/0/0
L       192.168.1.1/32 is directly connected, GigabitEthernet0/0/0
     192.168.2.0/24 is variably subnetted, 2 subnets, 2 masks
C       192.168.2.0/24 is directly connected, GigabitEthernet0/0/1
L       192.168.2.1/32 is directly connected, GigabitEthernet0/0/1
244boy
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2 Answers2

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As far as I know, the only thing which uses the "opposite mask" are the "wildcard bits" of access control lists in Cisco equipment. These can represent hosts or networks (and portions or aggregations of networks), but in practice they don't represent hosts because they are optional on Cisco IOS:

ip access-list standard NTPCLIENTS
 permit 192.168.0.0 0.0.255.255   # network
 permit 10.10.10.0 0.0.0.0        # host
 permit 10.10.10.0                # host

Edit: ... also in Cisco configurations, some parts of the OSPF configurations also use wildcard bits, not masks. It needs saying that it doesn't mean anything different, it's just a different way of writing it, required for no reason other than that's the way Cisco decided to do it.

jonathanjo
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1

You are mistaken as both the first two examples you provide are networks.

---Networks---
10.10.10.0 255.255.255.0 (dotted decimal)
10.10.10.0/24            (CIDR)
10.10.10.0 0.0.0.255     (wildcard mask)

Each of these examples provides the information that defines a range of IP addresses, specifically 10.10.10.0 - 10.10.10.255.

To indicate a single host or IP address, your mask or wildcard mask would have to indicate that only a single IP address was indicated. For example:

---Host---
10.10.10.0 255.255.255.255 (dotted decimal)
10.10.10.0/32              (CIDR)
10.10.10.0 0.0.0.0         (wildcard mask)
YLearn
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