BBC iD on CBBC
But migrating existing Children's services presented its own problems and a fair bit of head-scratching in the last few months.
With over 12 large scale games and activities (aimed specifically at 6-12s) already using the old SSO sign in system, the CBBC site represented the largest number of active SSO users in the BBC.
So it wasn't as simple as just turning on one system and pulling the plug on the other.
From audience feedback we know some of users have invested weeks, months and often years playing these games, nurturing their Roar safari parks, building up reputations and contributing UGC. It would be a hard man who would turn round and say all of that was for nothing. But more importantly we wouldn't want their enduring memory of BBC online services, during their most formative years, to be a sense that we just didn't care.
So the team had a double challenge to ensure that the data our users have amassed within their SSO accounts eg game points scored, saved submissions or progress within games would be follow with them to the new system whilst also protecting their safety.
Big challenge 1: Keeping user data
As SSO for CBBC did not require an email address to be provided during registration it was commonplace for users to open different accounts for each game or activity. The styling on individual games also seemed to confuse people that one sign in did not fit all. At one time we estimated there were 3 million active accounts amongst a potential available audience of just 4.2 million children.
By contrast the 'adult' full-fat BBC iD sign up requires users to provide an email address and limits users to one account per email address.
This gave us an important decision to make - do we ask users to select just one of their accounts and to resign themselves to losing all other accounts and the data saved against these accounts? Or do we allow users to transfer the data from all their accounts into their one new BBC iD account?
As recognition of the loyalty and commitment of our users, we decided to create a system by which they could keep their accounts.
A 'transfer' or 'coalescence' tool was built and users are passed through this (ably guided by a one-eyed bunny character) as part of the registration process. CBBC is unique within the BBC in offering this coalescence.
Challenge 2: Safety
As always safety of our users is paramount and, as such, with the launch of BBC iD, we have also taken the opportunity to add another layer of safety by introducing a Display Name Generator.
Whereas adults signing up to BBC iD can use any username they like and repeatedly change their display name through their account settings, this feature would create a major undertaking for CBBC in terms of additional moderation. Profanity filters can be used to ensure offensive screen names are excluded but we have an extra duty of care to guarantee kids don't inadvertently reveal their identities to all and sundry.
Consider an innocuous screen-name like MarcW127RJ. With a first name and postcode information like this, that child could be easily identified. (The astute among you will have worked out that's my work address).
So to help CBBC users keep themselves safe when signing up we also ask them to create a unique Display Name from a pre-filled word generator of random colours, adjectives and nouns. Expect to see a RedFieryLobster or ChocolatePancakeDude appearing on the messageboards anyday now.
Inevitably, some long-term regular users have objected to having the previous naming freedom restricted but when delved deeper we discovered most of these had actually outgrown our age band. And the children we've met in user testing seem to appreciate the safety benefits this system brings.
And it appears that our worst fears that children could just get confused by the whole process have been confounded.
In the first 10 days of offering the chance to coalesce data we have had over 45,000 users visiting the transfer tool and close to 72,000 users visiting the Display Name Generator (both old and new).
Any thoughts on how we can improve the process would be gratefully appreciated.
Marc Goodchild is Head of Interactive and On Demand, BBC Children's.