What is the need?
Consider an organization which has a high number of users. In this organization, a small minority (usually the top management) need all the collaboration features offered by O365 whereas the rest of the users mainly use only email. In such an organization, there is a requirement to host the email infrastructure of a company across 2 different solutions, such that both the solutions share the same SMTP address space and the company can divide their mailboxes across the two solutions.
For example, in an organization with 1000 users, a typical co-existence between Mithi SkyConnect and Microsoft Office 365 will allow the organization to host 100 users on O365 and 900 on Mithi SkyConnect, sharing a common domain name in their email ids, and with seamless mail flow between the users of both systems.
Watch this video to get a quick overview of how the co-existence solution works:
Why co-exist with Skyconnect?
- Co-existence enables the organization to optimize on the overall infrastructure, management and upgrade costs and at the same time ensure that the majority of the users remain on a flexible, reliable and secure cloud platform, which reduces TCO.
- The small minority of people who require the collabortaion features of O365 can continue to do so.
- Since the same domain is hosted on both the systems, the mail flow is seamless and transparent to the end users.
- The overall security of the setup increases as the incoming mail are checked for spam, virus and ransomware by the Trend Micro system servers.
- Coexistence with SkyConnect brings in value from the Open and free world, which gives the business an IT edge. For example, with open technologies, you could use any Android based phone/ pad/ tab, iPhone, iPad, to get seamless access to email, calendar, chat, and address book, while on the move. A possibility like this allows the field force to be more connected to each other and not just the top management.
How does Co-existence work?
To explain the working of co-existence, we have assumed an example domain of acmecorp.com and also assumed that there would be 100 users on Microsoft Office 365 and 900 users on the Mithi SkyConnect platform. The architecture is based on a loose coupling design, where the routing between the two systems happens via the Internet on the respective Mail Exchanger (MX) systems.
For the sake of understanding the flow, let us assume two users viz. o365user, whose mailbox is hosted on Microsoft O365 and mithiuser, whose mailbox is hosted on Mithi SkyConnect.
|Solution||Domain hosted||Sample User|
|Microsoft Office 365||acmecorp.com||o365user|
- On MS O365, provision the acmecorp.com domain and configure the 100 users, who will use the Microsoft o365 setup.
- On Mithi SkyConnect, provision the acmecorp.com domain and configure all the 1000 users as follows:
- 900 users will be pure SkyConnect users and their mailboxes will be hosted on SkyConnect
- The remaining 100 users hosted on O365 users will be added to the domain with the mailsystem set as “Others” and the mailboxlocation pointing to the O365 servers.
For details refer to this link.
Inbound Mail flow:
Inbound mail flow constitutes mail received from all external domains.
The MX for the acmecorp.com domain will land on Mithi SkyConnect. This means that inbound mail for all 1000 users will land on Mithi SkyConnect. Mail destined for any of 900 users, whose mailbox is on Mithi SkyConnect will be delivered and stored locally, whereas mail destined for any of the 100 users on O365 will be forwarded to the corresponding email id on O365.
The mail destined for the 0365 users will be routed as outbound traffic via the Internet.
Local Mail flow on acmecorp.com domain:
- O365 to O365: A user of the MS O365 system sends a mail to another user on the O365 system. This mail is routed internally within O365 and delivered to the recipient.
- O365 to Mithi SkyConnect: An acmecorp user of the O365 system sends a mail to another acmecorp user on the Mithi system (e.g. firstname.lastname@example.org sends a mail to email@example.com). The O365 system routes this mail via the secure send connector to Mithi SkyConnect, which accepts the mail and delivers it to the recipient’s mailbox. The mail flow is over the Internet.
- Mithi SkyConnect to O365: An acmecorp user of the SkyConnect system sends a mail to another acmecorp user on the O365 system. The Mithi system will attempt to deliver the mail to the acmecorp.com recipient on the Mithi system, who is configured to forward the mail to the corresponding email id on O365. E.g. if firstname.lastname@example.org sends a mail to email@example.com, the mail delivery configuration of this user instructs the Mithi system to forward the email to the receive connector on O365. The mail flow is over a secure Internet connection.
- Mithi to Mithi: An acmecorp user of the Mithi system sends a mail to another acmecorp user on the Mithi system. This mail is routed internally within the Mithi server and delivered to the recipient.
Outbound Mail flow:
- O365 to Internet: An acmecorp user on O365 sends a mail to an external recipient. This mail is routed to the Internet directly from the O365 system.
- Mithi SkyConnect to Internet: An acmecorp user on Mithi sends a mail to an external recipient. This mail is routed to the Internet directly from the Mithi SkyConnect system.
Virus and Spam control:
- Since the MX of acmecorp.com is landing on Mithi SkyConnect, the spam and virus scanning for all the mail is done by the Mithi SkyConnect system.
- Outbound mail from MS O365 may be scanned for Spam/Virus by the O365 system.
- Outbound mail from the Mithi system are not scanned for spam.
- The virus control engine is enabled on the Mithi system and all mail (inbound, outbound and local) are scanned for viruses.
To ensure that the recipients can perceive the hybrid mailing system to be one, it is important to configure the SPF record of acmecorp.com to contain the IP addresses of the outbound relay servers from both MS Office365 and the Mithi SkyConnect setup. The SPF record has to be configured with your DNS service provider.
The Mithi users will see the entire address book since all the 1000 users are added to the directory (although 100 of them will not have their mailboxes there). This makes it possible for the users of the Mithi system to see a complete global address book comprising of all 1000 users. As for the Office365 users, they will only see an address space of 100 users unless you can populate the Global address list on Microsoft Office 365 with all the 1000 users and also maintain this during provisioning (Adding and deleting users)
The users on O365 and Mithi will maintain their own passwords in the respective directories and via the respective interfaces. The password policies etc will apply from the separate systems respectively.
Mithi is the creator of Vaultastic – the easiest and safest cloud email archiving service, which has the capability to archive mail from both Microsoft Office 365 and Mithi SkyConnect (in addition to Google Apps/G Source, Hosted Microsoft Exchange, and others). To enable archival for the 1000 users of acmecorp.com, we would need to configure Vaultastic to receive archival mail from the 100 users on Microsoft 0365 and separately from the 900 users on Mithi SkyConnect.
In this architecture, the end user will have to create or remove users separately from Mithi and Office365. Is there a possibility to have a single address book.
In this design, which is a loose coupling design, there is no way to have a single address book. Just to clarify,
– when a new user joins on 0365, the user will have to be added on Mithi SkyConnect and 0365.
– when a new user joins on Mithi SkyConnect, the user will have to be added on SkyConnect and in the GAB of o365.
Groups: What if there is mix of users from Office365 and Mithi to be added to same distribution group or list?
This is not a problem on either system. Once the mail flow between the users of both systems is working fine, the distribution of mail via the DLs will also work fine.