A German politician got his metadata from his telco to show just how invasive it was. As a journalist, I also have concerns about what the Australian Federal Police can see when they investigate leaks to the media. Telstra had not revealed publicly in detail how long it stored customer metadata until I began asking questions. In December, for example, it told Fairfax Media that it stores metadata "for as long as it makes sense commercially and legally. For instance, we are required to hold billing data for up to six years to meet our obligations under the Telecommunications Consumer Protection Code". But through submissions and a legal hearing before the federal privacy commissioner with five Telstra representatives - including a senior network head - I've been able to ascertain more about Telstra's retention period of metadata and of telephone bills which contain far less information.

In the hearing, Telstra revealed it stored about 3000 terabytes worth of "network data" in total - its term for metadata - concerning all 16 million of its mobile phone subscribers for "network assurance" purposes. In other words, it stores this data to ensure its network operates as intended and it can assist customers when their phone or its network malfunctions. If a customer said their mobile service had no reception at home, for instance, Telstra could check this against their data. If the data showed there was no issue then Telstra could tell the customer that the problem may lie with their phone. Most interesting is the amount of metadata Telstra stores. The 3000 terabyte figure equals the same capacity of 192,000 16GB iPhones. This allows for a maximum of 30 days worth of certain customers' metadata to be retained, Telstra representatives said. Not all types of data - IP addresses, URLs accessed and so on - are stored for the 30-day period. Some metadata, such as who was behind a certain dynamic internet protocol (IP) address at a certain time is deleted after just three days, Telstra said. Another reason I want my metadata is to demonstrate visually to all Australians how personal it is. The data might also be useful if I ever decide to write a biography and couldn't remember where I was on a particular day. My metadata could tell me.

Wilson da Silva, a science journalist and a former editor-in-chief of science magazine Cosmos, recently argued that allowing people to access their metadata might actually improve their lives. I'm also not the first to want access to my data. German politician Malte Spitz successfully sued his telco in 2011 to get his metadata and published it to show constituents just how invasive having all of your metadata stored was in the wake of mandatory data retention in his country. Courts in Austria, Bulgaria, Cyprus, the Czech Republic, Germany, Romania and Slovenia have since ruled recently that mandatory data retention is unconstitutional, as has the European Court of Justice. Australia, however, has no constitutional protection when it comes to citizen privacy.

Some of the countries affected by the ruling have since altered their laws to allow for the retention of data again, such as the UK, which passed "emergency" laws to re-enact laws for the storage of the data. In trying to prevent me access to my records, Telstra said they were "unlikely to be complete" and could amount to "terabytes of data". After doing a primary school math equation, I argued that 3000 terabytes divided by 16 million customers did not mean my records could even be 1 terabyte (unless of course ASIO is watching and has asked my telco to preserve my data for a longer period.) Telstra also argued it would take a full-time person "up to two weeks to extract this data". The 30-day retention period is what Telstra's network engineer described as a "desire". And because its customer base keeps growing, the current period gets smaller and smaller, with new customers forcing the 3000 terabyte capacity to overflow earlier than the engineers would like.

The opportunity to store more data - which Telstra said would increase its attractiveness to hackers - is coming soon, with the Abbott government introducing what's been dubbed a "Data Retention Bill" into parliament last week. The scheme will force communications companies in Australia, including Telstra, Optus, Vodafone and iiNet, to store every subscribers' metadata for a period of up to two years just in case it's needed to solve a crime or find a terrorist. Web histories - URLs and IP addresses accessed - would not be required to be stored as part of the bill, although telcos may still want to store this data. It would be accessible under a warrant. I've been given no timeframe for when there'll be a determination in my case, but in any case you can expect Telstra to appeal to the Federal Circuit Court if it loses against me. And vice-versa. In the meantime, the movie studio behind Dallas Buyers Club is seeking IP address metadata from a range of Australian internet providers in the Federal Court to identify alleged pirates. Past cases show that companies have been forced to hand over such data in Australia.