Standard list and prefix list

Standard list and prefix list I. the anti-mask in the standard protection list is different from the anti-mask advertised in the routing protocol. For example, you can write access-list 1 permit 172.16.0.0 0.0.19.0, but not network 172.16.0.0 0.0.19.0 in the routing protocol. 172.16.0.0/24,172.16 .1.0/24,172.16 .2.0/24,172.16 .3.0/24172.16.16.0/24,172.16 .20./ 24,172.16 .18.0/24,172.16 .19.0/24 www.2cto.com write the changes to 0 based on the unchanged prefix; write 0 without changing the mask, and change write 1 to get the matching of the above eight routes in the Standard Control List: 172.16.0.0 0.0.19.0. Although there are more matching entries than the above eight entries, this is the most accurate match. II. the difference between access-list 1 permit 172.16.1.0 (1) and access-list 1 permit 172.16.1.0 0.0.255 (2) indicates that the method (1) matches all the same routes in the previous 24 s, if an entry such as 172.16.1.128/25 does not match, the method (2) means that all routes of 172.16.1.0/24 Match, including subnets in all ranges.
If Route 1: 172.16.1.0/25 and Route 2: 172.16.1.128/25 are available, when (1) is used for matching, only route 1 is matched. When (2) is used for matching, then both Route 1 and Route 2 will be matched. 3. The standard prefix list cannot match the mask. For example, access-list 1 permit 172.16.1.0 0.0.255 indicates that the mask can be 24 bits and 25 bits. Prefix list Syntax: ip prefix name permit x/y [ge A | le B] Where y <A <= B prefix list can precisely match the mask section: ip prefix-list name perimit 172.16.1.0/24 // indicates that the first 24 digits are fixed, the mask is a 24-bit ip prefix-list name permit 172.16.1.0/24 ge 25 // indicates that the first 24 bits are unchanged and the mask is between 25 and 32 bits. Ip prefix-list name permit172.16.1.0/24 le 32 // indicates that the first 24 BITs remain unchanged and the mask is 24 to 32 bits. Ip prefix-list name permit 172.16.1.0/24 ge 25 le 25 // indicates that the first 24 BITs remain unchanged and the mask is 25 bits.