Multi-Tenancy and Cherwell Service Management White Paper Release: NA CS-WPR-Multi-Tenancy Revision 1.0 30 July 2012 www.cherwell.com All Rights Reserved. Innovative Technology Built on Yesterday's Values
Copyright Cherwell Service Management and the Cherwell logo are trademarks or registered trademarks of Cherwell Software, Inc., in the U.S. and may be registered or pending registration in other countries. ITIL is a registered trademark of the Office of Government Commerce in the United Kingdom and other countries. PinkVERIFY is a trademark of Pink Elephant, Inc. All other trademarks, trade names, service marks and logos referenced herein are the property of their respective owners/companies. The information contained in this documentation is proprietary and confidential. Your use of this information and Cherwell Service Management is subject to the terms and conditions of the applicable End-User License Agreement and/or nondisclosure agreement and the proprietary and restricted rights notices included therein. All Rights Reserved. Cherwell Software, Inc. www.cherwell.com info@cherwell.com +1.719.386.7000 12295 Oracle Blvd., Suite 200 Colorado Springs, CO 80921 USA Revision History Revision Date Comments 1.0 30 July 2012 Initial release. Multi-Tenancy and Cherwell Service Management ii
Contents Abstract... 1 About this Document... 1 What Does Multi-Tenancy Mean?... 1 Shared Schema... 2 Licensing Considerations... 2 Shared Architecture... 3 Licensing Considerations... 3 Separate Instances... 4 Licensing Considerations... 4 How Does CSM Help with Multi-Tenancy?... 5 Security Groups... 5 Views... 6 Stored Searches... 6 Portal Sites... 6 External Tables... 7 Summary... 7 About Cherwell Software... 8 Contact Information... 8 Multi-Tenancy and Cherwell Service Management iii
Abstract There are two meanings to the term Multi-Tenancy, both at an architecture level and at the application level. This document investigates some of the meanings of multi-tenancy on both levels, and how Cherwell Service Management s rich and flexible functionality can help your business no matter what the needs. About this Document This document discusses the ways that Cherwell Service Management (CSM) can be configured and leveraged in a multi-tenant manner. There is one important distinction before we begin: Because Cherwell Software offers the Choice model with how the software is licensed, and we offer both on-premises and Software-as-a-Service (SaaS) options, it is easy to get the hosting model s architecture for hosting multiple customers confused with CSM s ability to offer multi-tenant features inside an individual customer s instance of the software. We have leveraged the latest in virtualization technology in our datacenters, which gives us the flexibility to offer our customers the most tailored of experiences. What this means is that any of our customers, regardless of the hosting model they have chosen, have access to the further ability to offer multi-tenancy functionality to their own end users. This document discusses multi-tenancy as a whole, and CSM s enabling features from the application point of view, rather than the architecture of a hosting environment. What Does Multi-Tenancy Mean? At the core, the concept of multi-tenancy is to isolate a user s data from the data of other users of the same system, meaning each user is able to connect to the same system individually and never know that other user s data even exists on the same system. Each user or group of users is called a tenant. The recent emergence of SaaS-only vendors times has popularized multi-tenancy design because it allows those vendors to gain economies of scale via shared hardware/software, simple upgrades, and centralized administration and reporting. In many cases, this is a simple choice of business and financial models for the vendor, and might not even have a relevant effect on product delivery to their customers in terms of end-user perception of functionality and reliability. On the other hand, as a customer or potential CSM customer you might need to decide how to set up your system to accommodate your business and financial needs. There are three common approaches to multi-tenancy, from a technical standpoint. For this article, we will refer to them as: Shared Schema. Shared Architecture. Separate Instances. Multi-Tenancy and Cherwell Service Management 1
Shared Schema The Shared Schema approach is a very common approach that involves all users accessing the same application, with strict security to segregate data by user or groups of users. This comes with pros and cons. While the system is easier to administrate in many ways because there is only one application, it also means that groups of users cannot have wildly different user experiences based on their business needs. Sometimes this approach is touted as the only true multi-tenancy approach, but that is somewhat of a purist viewpoint that overlooks many real-world business needs. For CSM, the Shared Schema approach can work well for departments or divisions of an organization, or to apply differentiation to different campuses or regional offices. It assumes similar data model and similar business logic applies across the board, but can still offer some significant customization opportunities for each user group. Tenant A Tenant B Tenant C DBMS Server Shared Some Shared Schema models allow for some level of differentiation of business processes, look and feel, and data modeling. CSM provides several features to allow for this that are covered later in this document. Licensing Considerations The Shared Schema model offers the most flexible licensing option. Because all users are in one single set of database tables, a single pool of concurrent licenses can be utilized by all, bringing a potential savings. Multi-Tenancy and Cherwell Service Management 2
Shared Architecture The Shared Architecture model provides the ability to offer very different business needs to very different groups of users. What is lost in easy central administration and reporting is gained in the ability to deliver completely different data models and business logic to different user groups. This approach can work well for Managed Service Providers and other service agencies that serve different groups of customers with varying business models, while still offering an economy-of-scale benefit on the infrastructure side. This approach is sometimes called a hybrid model by some tech writers and bloggers. For CSM, this approach can make a lot of sense if you have groups of users that require autonomous (as opposed to centralized) administration of their own data models and/or business logic. Tenant A Tenant B Tenant C VM App A App B App C DB A DB B DB C DBMS Server Licensing Considerations Because the Shared Architecture model splits the user groups into separate databases, this approach requires separate pools of licenses for each group of users. These are still concurrent seat licenses, but on a group-by-group basis as separate license keys from Cherwell. While one might lose the easy reallocation of licenses between groups, it is not necessarily a bad thing; this can, in some cases, simplify the internal accounting and billing associated with each group. Multi-Tenancy and Cherwell Service Management 3
Separate Instances The Separate Instance approach is perhaps the most drastic approach to tenancy and is sometimes known as single-tenancy. This is much like the old Service Provider (ASP) model, where every user group has its own completely separate infrastructure. This is useful in situations where: High security is a must, such as Government or healthcare. User groups require data-at-rest encryption or alternative access via VPN tunnels, or the like. Very high-volume user groups have high performance demands. User group needs are so wildly different that they offer no similarities to other user groups. With this approach, the idea of central administration efficiency gains is usually abandoned in favor of a fortress-style approach for each user group. You can still achieve modest economy gains by utilizing virtualization technologies with this approach. Tenant A Tenant B Tenant C Licensing Considerations The Separate Instance model, as with the Shared Architecture model above, requires a separate license pool for each group of users. Multi-Tenancy and Cherwell Service Management 4
How Does CSM Help with Multi-Tenancy? Regardless of the approach taken, CSM offers quite a few features that assist with successful multi-tenant implementations. Security Groups From creating and editing records, to searching, Dashboards, and reporting, a CSM Security Group always ensures that the user can only see the data that they are allowed to see. Security Groups allow the system administrator to set very granular rights down to the field level for different groups of users. Because Security Groups are down to the field level, they offer the system administrator the ability to have some level of customized data, even within a Shared Schema approach. Business Object Tenant A SharedField1 SharedField2 SharedField3 CustomFieldA1 CustomFieldA2 CustomFieldB1 CustomFieldC1 Tenant B Tenant C Shared Fields In addition to the object and field level security, CSM Security Groups also allow for dynamic criteria-based security clauses. This allows the system administrator to separate groups of users data based on an ID or organizational Name column. What s the most powerful thing about CSM and how it leverages security? CSM security applies to all aspects of the system. There are no holes where a user can run a search or process a report that does not run through the constraints of the user s Security Group. This brings users (and system administrators) the peace of mind that the data is safely secured. Multi-Tenancy and Cherwell Service Management 5
Views In addition to the powerful security features of CSM, there is another layer that is very useful for Shared Schema implementations: Views. Views are a method of creating separate UI and business logic for different groups of users, but on top of the same database tables. The end result is a tailored experience for each user group, but the ability for all data to still be central and reportable at a corporate level. Tenant A Tenant B Tenant C DBMS Server Stored Searches One of the many powerful features of CSM is what we call a Stored Search. A Stored Search can be used for basic queries of user data or for building very complicated queries involving related items. After a Stored Search is saved to the system, it can be utilized to drive grids of data, charts, graphs, and even printed reports from our powerful Report Builder. A system administrator can easily tailor searches to different groups of users, and only return the data that is useful to that group. While this is not as secure as using Security Groups to separate data, this can be useful in many environments where strict security is not necessary between groups, and the desire is to simply work with just the data that the users of that group care about. Portal Sites CSM offers one of the most flexible end-user portal systems on the market today, giving customers the ability to create any number of Sites that can offer completely individualized functionality, look and feel, Business Objects, reports, and more. These Sites can also leverage the features above, such as Security Groups and Views to provide a completely tailored yet secure experience for each group of users. Multi-Tenancy and Cherwell Service Management 6
External Tables Even if you chose a Shared Architecture or Separate Instances approaches, CSM offers features above-and-beyond the competition that can still allow you to have some level of centralized application functionality, Dashboards, and reporting. This is accomplished by using External Tables. It requires a bit of pre-planning and some extra configuration, but it brings a lot of power. The CSM External Table features allow you to treat a Business Object from another database as if it were internal to the CSM system. By setting up a central CSM system, and then accessing and mapping data from the different user group systems, you can gain the central business metrics and decision making ability normally only found by using the Shared Schema approach. Tenant A Tenant B Tenant C Corporate Summary To sum up, from a pure Shared Schema approach, to hybrid models, to completely Separate Instances, CSM has the tools to enable you to choose the right tenancy approach for your business. Multi-Tenancy and Cherwell Service Management 7
About Cherwell Software Cherwell Software is the developer of Cherwell Service Management, an integrated service management software solution for IT and support professionals. Cherwell Service Management (CSM) was designed from the ground up using Microsoft s.net technology and Out-Of-The-Box ITIL best practices. With fully integrated modules that have received PinkVERIFY certification such as Incident Management, Problem Management, Change Management, Release Management, Configuration Management, and Service Level Management, just to name a few, CSM provides a holistic approach to service management, allowing IT and support departments to align themselves with the businesses and customers they support. CSM offers enterprise power with mid-market prices and ease-of-use. Cherwell Software s customers include such companies as TV Guide, The Weather Channel, Ent Federal Credit Union, The University of Minnesota, Hallmark Services and Ohio State University. Headquartered in Colorado Springs, with European offices in England, Cherwell Software was founded and is managed by a team of industry experts, including the former CEO of Front Range Solutions, the former Chief Architect of Front Range Solution s HEAT and ITSM product lines, and the original founder and past CEO of the Help Desk Institute (HDI). We are passionate about customer care and "innovative technology built upon yesterday values." Please visit www.cherwell.com for more information about Cherwell Software. Contact Information Support Website: Sales Website: Support E-mail: Sales E-mail: www.cherwellsupport.com www.cherwell.com support@cherwell.com sales@cherwell.com Corporate Headquarters/North America Support Phone: Sales Phone: +1.719.386.7000 x3 +1.719.386.7000 x1 Address: 12295 Oracle Blvd., Suite 200 Colorado Springs, CO 80921, USA EMEA Sales Phone: +44 (0)1793 858181 Fax: +44 (0)800 098 8066 Address: Lime Kiln House Lime Kiln Wootton Bassett, SN4 7HF, UK Multi-Tenancy and Cherwell Service Management 8