A whitepaper on the client-side vs server-side sync written based on our team's experience. All the cons and pros for those who are researching both options.

1. OutlookBridge-based vs Direct Exchange
Integration for Contact and Activity
Processing
Comparison Guidelines
Prepared By: 650 Castro street, Ste. 120/385 Mountain View, CA, 94041 www.invisiblecrm.com

2. The Problem
Whenever CRM/ERP/Social (LOB from now on) software vendors start solving the problem of integrating
activity management in their contacts and activities management functionality with that in Outlook,
there are a lot of possible solutions.
Solutions range by complexity - from one-way activity publishing from LOB to user Outlook, to solutions
with full-featured and seamless synchronization.
Given the complexity of such integration, correct comparison criteria may help a lot in choosing the right
path. This article provides our view on such criteria and compares two approaches an integration
solution may be based upon.
Selection Criteria
Designing the correct solution requires careful prioritization of functionality, with focus on the following:
1. Full synchronization versus replication.
2. Support for Calendars, Tasks, Emails, and Contact synchronization:
a. Custom objects support is a big plus;
b. Custom fields on standard objects is a big plus;
c. Email synchronization has specific integration scenarios (emails typically are not
synchronized but selectively replicated).
3. Granular selection of what to synchronize and what to keep private.
4. Seamless synchronization and collision resolution:
a. Policy-based: server wins, client wins;
b. Controlled by the user;
c. As detailed as field-by-field merging.
5. Heterogeneous environments support. Some clients may be on Exchange, some may have
Internet mail accounts set up and store mail and calendar items in a .pst.
6. Presence of configuration applications for both administrators and end users to select what to
synchronize and when.
7. Complexity of Exchange configuration to deploy the solution.
8. Support of standard activity processing scenarios in Outlook/Exchange (recurrences, exceptions,
participant parsing, time zones) as well as advanced scenarios (shared folders, delegate access,
different Outlook versions on computers accessing the same Exchange mailbox).
9. Client independency – enable Windows, Mac and mobile users to use the integration.
10. Completeness of LOB API – different LOB provide varying level of activity processing support,
some APIs can handle only simple scenarios.
11. Developing a custom solution versus basing the solution on a proven platform.
12. Productivity features and advanced scenarios in addition to basic data synchronization.
© 2005-2011 InvisibleCRM®. All rights reserved. 2
InvisibleCRM® and InvisibleCRM® logo are trademarks of Avora Holdings, Inc. All other product names are used for
identification purposes only and may be trademarks of their respective holders.

3. 13. Onboarding – initial installation of the product to the mailbox which already has potential
duplicate contacts.
14. Co-existence with other synchronization solutions.
15. Upgradability of solution and no vendor lock-in.
This document leaves aside one-way publishing/replication solutions since they address problem only
partially. Instead, our comparison focuses on the following two ways of integrating – direct
synchronization between Exchange and LOB system and OutlookBridge-based approach working from
Outlook.
Exchange to LOB Direct Integration
Pros
 Client-independent, user can be on Windows, Mac or on mobile.
 No software installed on client.
Cons
 Requires a desktop or web application to administer which data to synchronize for each user,
and to enable users for such synchronization.
 Requires an application to manage user-specific settings like filters, and it is a complex task to
present users with a flexible solution to configure granular filters for selecting what to
synchronize.
 Makes it difficult for the user to mark what is private and what is shared in their calendars.
 While a solution can synchronize tasks and appointments, automatic email sharing requires
separate design since emails are not good for bi-directional synchronization, and decision on
what to share is typically user-controlled.
 Does not provide fine-grained collision resolution, can only use "LOB always wins" or "Exchange
always wins" patterns as no user interaction is possible for the server-side solution.
 No LOB extended data attributes. Limited to standard fields of Outlook items - not possible to
have LOB-specific fields or associate with custom objects.
 It is a complex task to match Exchange activity processing model and LOB activity model as there
are a lot of specifics, such as:
 Recurrences and recurrence exceptions;
 Automatic or manual participant parsing;
 Time zones support;
 Differences between activities originated in LOB and in Outlook;
 Activity ownership concept in Exchange and LOB are typically different;
 Requires impersonation setup for LOB and for Exchange to enable server-side synchronization to
work on behalf of all users. Possibly, custom modules may be required to install on Exchange
servers. Both of these may require on-premise Exchange configuration because hosted
Exchange configurations may lack that configurability options.
© 2005-2011 InvisibleCRM®. All rights reserved. 3
InvisibleCRM® and InvisibleCRM® logo are trademarks of Avora Holdings, Inc. All other product names are used for
identification purposes only and may be trademarks of their respective holders.

4.  Any “above-the-minimal” Exchange to LOB integration requires investment into a new custom
product to be developed, stabilized, and rolled out.
 Deployment of Exchange-based synchronization in large corporate environments is challenging
to configure and complex to support.
 A lot of large software companies have started from server based solutions and ended up
shelving those due to complexity, instability and lack of value to the user, in favor of client-
based synchronization.
OutlookBrigde-based Integration
Pros
 Available as OutlookBridge platform, requires only the development of the LOB-specific
connector and customization. (May still need API changes to comply with OutlookBridge
platform sync API requirements).
 A lot of corner cases with activity processing are already researched and implemented in the
current OutlookBridge platform, and the platform is constantly improving.
 Granular filters to define which activities should be synchronized. Filters are managed by both
administrators (via customization packages) and end-users.
 Level of activity processing support includes:
 Recurrences and recurrence exceptions;
 Automatic or manual participant parsing;
 Time zones support;
 Activity de-duplication support.
 Selective sharing of information – users themselves define what to share and what to keep
private with the two different patterns available out of the box – “share the most, and let me
unshare what I do not want to share” or “share the least, and let me pick what to share”.
 Synchronization model in OutlookBridge can be adapted to existing LOB API, gracefully
downgrading the integration level to the one supported by the LOB API.
 Supports custom fields – Tasks, Appointments, Emails, and Contacts can get custom fields to
provide LOB data in Outlook as needed.
 Supports custom objects - allows association of tasks, appointments and emails with LOB-
specific objects.
 Supports different approaches for associating emails. Email can be shared with LOV as a whole,
with or without attachments, or custom logic can be implemented such that it can be defined
where to put the email attachments in the LOB system.
 Users can do most of the synchronization filters configuration themselves from Outlook.
 Fine-grained collision resolution. Users resolve collisions manually in Outlook or may set up rules
for automatic resolution.
 Heterogeneous configuration support. Some users may still use Internet email accounts (data
will be stored in a .pst file), while others can be on Exchange – it just works.
© 2005-2011 InvisibleCRM®. All rights reserved. 4
InvisibleCRM® and InvisibleCRM® logo are trademarks of Avora Holdings, Inc. All other product names are used for
identification purposes only and may be trademarks of their respective holders.

5.  Does not require Exchange configuration changes, users become productive immediately after
they install (except the cached mode requirement, which itself is typical these days). No need to
modify the Exchange server in larger accounts where that might be an IT control and security
issue.
 Full product functionality is available offline thanks to the full Object Data Model being
integrated and contained within Outlook storage.
 Supports various productivity features like:
 extensive data validation to improve data quality and reduce human errors;
 data prefilling to make it faster for users to enter data into the system;
 calculated fields support;
 reflection of LOB security rules into Outlook, so that the user can’t edit in Outlook what is
read only to him in LOB;
 auto-suggest when associating items with LOB data;
 automatically saving correspondence for a given person;
 one-click initiation of meetings/emails to customer team or to internal team working on a
particular topic/opportunity;
 ability to open a specific item directly in web for detailed drill-down
Cons
 Partially client-dependent. Requires Outlook to be running for synchronization between LOB and
user mailbox/calendar to happen:
 Allows mobile to synchronize with Exchange, letting Outlook to do heavy-lifting for moving
data between Exchange and LOB;
 Any Exchange originated activity is available immediately to Exchange users; delay is only
with reflection of that in LOB.
 Requires software to be installed on Windows box.
Future
It is important to note that InvisibleCRM is working on a hybrid platform which is going to provide LOB
to Exchange synchronization without the need of having Outlook up and running for synchronization to
happen, and keep all the productivity features of the current OutlookBridge offering.
The new platform capabilities will allow making the solution client-neutral, that is, Windows, Macs and
mobile devices can work directly with Exchange and have the data repli cated in LOB using automatic
rules set up by users. Outlook still remains as a rich client providing current OutlookBridge functionality
and enabling more scenarios for users.
Once available, the new platform will provide clear migration path for existing OutlookBridge customers,
and leverage the new functionality.
© 2005-2011 InvisibleCRM®. All rights reserved. 5
InvisibleCRM® and InvisibleCRM® logo are trademarks of Avora Holdings, Inc. All other product names are used for
identification purposes only and may be trademarks of their respective holders.