Firstly i am resolving this stun server "stun2.l.google.com:19302" which has high priority.
StringVector servers = new StringVector();
if (stunservers == null || stunservers.size() < 1) {
servers.add("stun2.l.google.com:19302");
} else {
for (String s : stunservers) {
servers.add(s);
}
}
mEndpoint.natUpdateStunServers(servers, true);