$ip = '111.222.333.444';
if ( preg_match('/([0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}):?([0-9]{1,5})?/', $ip, $match) ) {
   echo 'ip: ' . $match['1'] . (isset($match['2']) ? ' port: ' . $match['2'] : '');
}

(?::                #Match the :
  (?![7-9]dddd) #Ignrore anything above 7....
  (?!6[6-9]ddd)  #Ignore anything abovr 69...
  (?!65[6-9]dd)   #etc...
  (?!655[4-9]d)
  (?!6553[6-9])
  (?!0+)            #ignore complete 0(s)
  (?<Port>d{1,5})
)?

if (preg_match(
    '/b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)
    (?::
      (?![7-9]dddd) #Ignrore anything above 7....
      (?!6[6-9]ddd)  #Ignore anything abovr 69...
      (?!65[6-9]dd)   #etc...
      (?!655[4-9]d)
      (?!6553[6-9])
      (?!0+)            #ignore complete 0(s)
      (?P<Port>d{1,5})
    )?
    b/x',
    $subject)) {
    # Successful match
}

b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?):d{1,5}b

[0-9]{3}.[0-9]{3}.[0-9]{3}.[0-9]{3}:[0-9]{5}