Bash script update he ipv6 tunnel info

HE.net ipv6 tunnel end

#!/bin/bash
#
#Script to update ip on Hurricane Electric every 30 minutes
#@author Aaron Ogle

#Variables
HE_userid=<userid>
HE_passwd=<password hash>
HE_tunnelid=<tunnelid>

#Get current ip.
CurrentIP=$(curl -s checkip.dyndns.org|sed -e 's/.*Current IP Address: //' -e 's/<.*$//')

#Initial update to services
echo ***Starting update script***
HE_updateparms='ipv4b='$CurrentIP'&user_id='$HE_userid'&pass='$HE_passwd'&tunnel_id='$HE_tunnelid
curl -F $HE_updateparms http://ipv4.tunnelbroker.net/ipv4_end.php
echo 'Ip set:'$CurrentIP
#Loop to keep time updated
address='dynamic'
until [$address -eq 'static'];
   do


   #Get Current IP again.
   IP=$(curl -s checkip.dyndns.org|sed -e 's/.*Current IP Address: //' -e 's/<.$//')

   if ["$CurrentIP" != "$IP"];
   then
      #Could use AUTO instead of passing.  But were've already got it.
      #Might as well pass it
      curl -F $HE_updateparms http://ipv4.tunnelbroker.net/ipv4_end.php
      echo 'Updated IP:'$IP
   else
      echo 'Unchanged.'
   fi

   #Sleep for 30 Minutes
   sleep 1800

   done