Mr Amirul Hafiz had sent me a few messages about the location of certain cell towers. He brought up to my mind that in some cases, the GSM tracker gives a location in UK while the actual location is in Malaysia. What’s even more awkward is that sometimes a cell tower could not be found and later I found it in my local database. As a matter of fact this is not the first time I have received such questions.

The requests have much to do with data. I now have one database online and another on my laptop, I usually process data on local server before uploading it to my online server. After years of backup I accumulated way more data on my computer than the online server, and it’s for a reason.

As you may know, you only need LAC and CID to do a search in the past. This worked rather smoothly for a few years. As I had been gathering more and more data, I began to run into issues.

When I started offering the service online, I had only 10 million unique cell towers. Now the number nearly tripled and amounts to over 40 millions (exclude China which alone has 10 million cell towers) and counting.

I emphasize unique is that I do not want to store duplicate data on my server. Duplicate entries on one hand slow down the search, and on the other hand eat up too much storage, although I do not have such worries on my laptop which has over 3T storage.

With such a huge amount of data, I created a unique index on LAC and CID to speed up searches. However I began to realize that a lot of cell towers have the same LAC and CID, the only difference is MCC and MNC. Since I have an index on LAC and CID, all similar data are ignored when I upload the data. That is why if you do a search with LAC and CID only, it could pinpoint the cell tower to another country, not to mention a lot of cell towers could not be found just because it has the same LAC and CID with some base stations already in database.

Giving the scale of duplicate entries, I started to use MCC-MNC-LAC-CID as index. In the meantime I re-uploaded the local data to my server and had some 8 million of extra cell towers inserted.

This could have some minor impacts on your daily usage. From now on you need to enter all values for MCC, MNC, LAC and CID to find a cell tower. According to my calculations, the number of cell towers missing MCC and MNC is merely 20 thousands in my database. That is, in rare cases (5/10000), you can still find a cell phone tower using LAC and MCC only. But I strongly recommend you enter all fields otherwise it could have no or incorrect result even though it’s included in my database.

Another impact would be that it will be little slower than before. But I bet you would not notice that.

The good news is that you it won’t give you incorrect locations in the future, LOL.