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The risk of letting the coordinator parse this schema is that it will be harder to make changes to it in the future. For example, if we want to add a new field, we will have to be careful to upgrade the broker before the clients which which depend on the new field. To address this problem, we propose to let the coordinator parse this data as version 0 only. Effectively it will ignore the value of the version field and just look for the array of subscribed topics. Any trailing bytes will be ignored. Future protocol changes will have to preserve the topic list.

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