Cross-Domain Zimbra Calendar Sync

I need a viable solution which can be hosted in a typical LAMP environment which will allow multiple Zimbra 7 OSE calendars to be synched between multiple Zimbra 7 OSE servers.

To give more clarity, here is a description of the challenge being faced:

I have multiple companies. Each company runs a separate Zimbra 7 OSE server. I have an account on each of the servers--and each account has its own calendar. I need all of the calendars to automatically synchronize multi-directionally.

I do *not* want to simply have all my calendars appear in each account's calendar list. I want 2 to 5 separate calendars to synchronize so that all are identical within five minutes of any change made on any calendar in the group.

The language to be used should be something standard like PHP or Python and the protocol for interacting between the calendars should be whatever can do so securely and is a typical method for Zimbra 7 OSE (CalDAV seems to be the best choice, since that is how my Android phone synchs bi-directionlly with one of my calendars). I'm perfectly happy to build a dedicated server for this purpose, so the environment can be customized as needed.

Part of the prjoject is to provide writtten instructions on how to create more "cluster connections" since I am not the only user in the situation of needing to sync multiple calendars.

I am not interested in synching tasks nor in synching email--just calendars.

I am sure I need to provide more details, so if you post a question, I will add "project clarifications"

Thanks!

PHP Software Architecture

Project ID: #1534271

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