Exam JN0-231 topic 1 question 92 discussion

got it even though the 173.145.5.21 255.255.255.0 is accepted in the address book it shows as a /32 same goes for the 203 address

some one explain please just did this on my srx with the slash / they are not valid set address 173.145.5.21/255.255.255.0 set address 153.146.0.145/255.255.0.255 a space in between prefix and mask are valid set address 173.145.5.21 255.255.55.0 set address 153.146.0.145 255.255.0.255 these two are valid and accepted in address book set address newyork 191.168.203.0/24 this is valid as well not valid set address ABCD 203.150.108.10/24 even if you type the below set address 203.150.108.10/24 203.150.108.10/24 address-book { address 173.145.5.21 255.255.255.0/32; address 153.146.0.145 255.255.0.255/32; address newyork 191.168.203.0/24; [edit security zones security-zone trust address-book] 'address 203.150.108.10/24' Invalid address entry<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<invalid

the two valid address book entries are: C. 203.150.108.10/24 D. 191.168.203.0/24 A. 173.145.5.21/255.255.255.0: This is a mix of an IP address and a subnet mask, but in a format that's not typically used for address book entries. Address book entries usually use CIDR notation, not a combination of an IP address and a traditional subnet mask. B. 153.146.0.145/255.255.0.255: This option is invalid because the part after the slash is supposed to be a subnet mask in CIDR notation (which is a number between 0 and 32 for IPv4), but "255.255.0.255" is not a valid subnet mask in any format. C. 203.150.108.10/24: This is a valid address book entry. It uses CIDR notation, where "/24" indicates the subnet mask (255.255.255.0 in traditional format), and "203.150.108.10" is the IP address. D. 191.168.203.0/24: This is also a valid address book entry. Here, "/24" is the CIDR notation for the subnet mask, and "191.168.203.0" is the network address.

B - That's how you configure 'WildCard' address. D - Valid /24 address.

why b and d?

A,D correct answer