Performing NAPTR queries on Windows

While testing out my PowerDNS setup, which I blogged about yesterday I discovered that nslookup can not perform NAPTR queries.I poked around for a while to see what I was doing wrong, however it seems that even though Windows Server supports supplying NAPTR responses to DNS nslookup can not perform this query. (Yeah this seems odd to me as well.)

Thankfully I found this easy to use port of dig for Windows and within 30 seconds of downloading it I was performing successful NAPTR queries from my windows box. It is worth grabbing if you need anything beyond simple DNS queries on your windows box.

Setting up PowerDNS for ENUM

I have a few installations coming up that are going to be using ENUM for call routing. ENUM is a form of DNS that allows mapping of telephone numbers to URIs. While I understand the idea behind ENUM and how it works in a basic sense I wanted to get some hands on experience. So with that in mind I decided to set-up PowerDNS. I built mine within a VM running Cent OS but it can easily run on any version of *nix.

There are heaps of guides out there on how to set it up and I ended up using a combination including this one. Now, I didn't end up installing PowerAdmin as really it seemed like overkill in my case so I just stopped at step 3. Now all that is left is to add ENUM records into the database. These are simply standard NAPTR records with the correct format for ENUM which is specified in RFC 2916. I followed the instructions here, mainly because SQL is something that I can never seem to remember after a few days. 

Obviously I wanted to check that I had everything set-up by performing some queries. In my case local queries worked fine but I had some troubles with remote queries, I was getting no response. Stopping iptables sorted this out for me, obviously in a more permanent machine you would want to open up the firewall not remove it completely. Finally, while nslookup worked great for normal DNS queries it couldn't perform NAPTR queries so I had to turn to a windows port of dig, which can be found here.

Wifi Roaming

Some of you may have read my post a week or so ago entitled Wifi is too Fiddly. Well, according to this press release on Engadget it seems that the GSMA and WBA agree with me. It is nice to feel vindicated.

Essentially they are proposing that SIM based authentication could be utilised to connect to WiFi access points. Thus your mobile service provider could setup some access points in areas where there is very high data usage and shift users onto this, thus freeing up the radio network for voice traffic and users outside the wireless range. Areas like airports and train stations immediately spring to mind for this type of hand off.