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ipv6_compare()

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Compares two IPv6 or IPv4 network address strings. The two IPv6 strings are parsed and compared while accounting for the combined IP-prefix mask calculated from argument prefixes, and the optional PrefixMask argument.

ipv6_compare('::ffff:7f00:1', '127.0.0.1') == 0
ipv6_compare('fe80::85d:e82c:9446:7994', 'fe80::85d:e82c:9446:7995')  < 0
ipv6_compare('192.168.1.1/24', '192.168.1.255/24') == 0
ipv6_compare('fe80::85d:e82c:9446:7994/127', 'fe80::85d:e82c:9446:7995/127') == 0
ipv6_compare('fe80::85d:e82c:9446:7994', 'fe80::85d:e82c:9446:7995', 127) == 0

Note

The function can accept and compare arguments representing both IPv6 and IPv4 network addresses. However, if the caller knows that arguments are in IPv4 format, use ipv4_is_compare() function. This function will result in better runtime performance.

Syntax

ipv6_compare(Expr1, Expr2[ ,PrefixMask])

Arguments

  • Expr1, Expr2: A string expression representing an IPv6 or IPv4 address. IPv6 and IPv4 strings can be masked using IP-prefix notation (see note).
  • PrefixMask: An integer from 0 to 128 representing the number of most significant bits that are taken into account.

IP-prefix notation

It's common practice to define IP addresses with IP-prefix notation using a slash (/) character. The IP address to the LEFT of the slash (/) is the base IP address, and the number (1 to 127) to the RIGHT of the slash (/) is the number of contiguous 1 bits in the netmask.

For example, fe80::85d:e82c:9446:7994/120 will have an associated net/subnetmask containing 120 contiguous bits.

Returns

  • 0: If the long representation of the first IPv6 string argument is equal to the second IPv6 string argument.
  • 1: If the long representation of the first IPv6 string argument is greater than the second IPv6 string argument.
  • -1: If the long representation of the first IPv6 string argument is less than the second IPv6 string argument.
  • null: If conversion for one of the two IPv6 strings wasn't successful.

Examples: IPv6/IPv4 comparison equality cases

Compare IPs using the IP-prefix notation specified inside the IPv6/IPv4 strings

datatable(ip1_string:string, ip2_string:string)
[
 // IPv4 are compared as IPv6 addresses
 '192.168.1.1',    '192.168.1.1',       // Equal IPs
 '192.168.1.1/24', '192.168.1.255',     // 24 bit IP4-prefix is used for comparison
 '192.168.1.1',    '192.168.1.255/24',  // 24 bit IP4-prefix is used for comparison
 '192.168.1.1/30', '192.168.1.255/24',  // 24 bit IP4-prefix is used for comparison
  // IPv6 cases
 'fe80::85d:e82c:9446:7994', 'fe80::85d:e82c:9446:7994',         // Equal IPs
 'fe80::85d:e82c:9446:7994/120', 'fe80::85d:e82c:9446:7998',     // 120 bit IP6-prefix is used for comparison
 'fe80::85d:e82c:9446:7994', 'fe80::85d:e82c:9446:7998/120',     // 120 bit IP6-prefix is used for comparison
 'fe80::85d:e82c:9446:7994/120', 'fe80::85d:e82c:9446:7998/120', // 120 bit IP6-prefix is used for comparison
 // Mixed case of IPv4 and IPv6
 '192.168.1.1',      '::ffff:c0a8:0101', // Equal IPs
 '192.168.1.1/24',   '::ffff:c0a8:01ff', // 24 bit IP-prefix is used for comparison
 '::ffff:c0a8:0101', '192.168.1.255/24', // 24 bit IP-prefix is used for comparison
 '::192.168.1.1/30', '192.168.1.255/24', // 24 bit IP-prefix is used for comparison
]
| extend result = ipv6_compare(ip1_string, ip2_string)
ip1_string ip2_string result
192.168.1.1 192.168.1.1 0
192.168.1.1/24 192.168.1.255 0
192.168.1.1 192.168.1.255/24 0
192.168.1.1/30 192.168.1.255/24 0
fe80::85d:e82c:9446:7994 fe80::85d:e82c:9446:7994 0
fe80::85d:e82c:9446:7994/120 fe80::85d:e82c:9446:7998 0
fe80::85d:e82c:9446:7994 fe80::85d:e82c:9446:7998/120 0
fe80::85d:e82c:9446:7994/120 fe80::85d:e82c:9446:7998/120 0
192.168.1.1 ::ffff:c0a8:0101 0
192.168.1.1/24 ::ffff:c0a8:01ff 0
::ffff:c0a8:0101 192.168.1.255/24 0
::192.168.1.1/30 192.168.1.255/24 0

Compare IPs using IP-prefix notation specified inside the IPv6/IPv4 strings and as additional argument of the ipv6_compare() function

datatable(ip1_string:string, ip2_string:string, prefix:long)
[
 // IPv4 are compared as IPv6 addresses 
 '192.168.1.1',    '192.168.1.0',   31, // 31 bit IP4-prefix is used for comparison
 '192.168.1.1/24', '192.168.1.255', 31, // 24 bit IP4-prefix is used for comparison
 '192.168.1.1',    '192.168.1.255', 24, // 24 bit IP4-prefix is used for comparison
   // IPv6 cases
 'fe80::85d:e82c:9446:7994', 'fe80::85d:e82c:9446:7995',     127, // 127 bit IP6-prefix is used for comparison
 'fe80::85d:e82c:9446:7994/127', 'fe80::85d:e82c:9446:7998', 120, // 120 bit IP6-prefix is used for comparison
 'fe80::85d:e82c:9446:7994/120', 'fe80::85d:e82c:9446:7998', 127, // 120 bit IP6-prefix is used for comparison
 // Mixed case of IPv4 and IPv6
 '192.168.1.1/24',   '::ffff:c0a8:01ff', 127, // 127 bit IP6-prefix is used for comparison
 '::ffff:c0a8:0101', '192.168.1.255',    120, // 120 bit IP6-prefix is used for comparison
 '::192.168.1.1/30', '192.168.1.255/24', 127, // 120 bit IP6-prefix is used for comparison
]
| extend result = ipv6_compare(ip1_string, ip2_string, prefix)
ip1_string ip2_string prefix result
192.168.1.1 192.168.1.0 31 0
192.168.1.1/24 192.168.1.255 31 0
192.168.1.1 192.168.1.255 24 0
fe80::85d:e82c:9446:7994 fe80::85d:e82c:9446:7995 127 0
fe80::85d:e82c:9446:7994/127 fe80::85d:e82c:9446:7998 120 0
fe80::85d:e82c:9446:7994/120 fe80::85d:e82c:9446:7998 127 0
192.168.1.1/24 ::ffff:c0a8:01ff 127 0
::ffff:c0a8:0101 192.168.1.255 120 0
::192.168.1.1/30 192.168.1.255/24 127 0