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Decision Framework, DF-16-9975B. Elliot

Research Note2 August 2002

Contact Center Architecture Layers Are Key

Contact centers are shifting away from vertically integratedmodels to a distributed, component-based architecture. Asthis occurs, enterprises must view the technology in termsof functional layers.

Defining functional layers of a contact center's infrastructure andapplications greatly simplifies the task of integration andmigration. In many cases, it is not possible to develop aneffective architecture without defining layers of functionality. Ascontact centers continue to evolve toward a software-basedcomponent architecture, the use of layers becomes increasinglycritical. Failure to define these layers typically results inincompatible "silos" of application-specific functionality, as wellas difficulty in integrating the components. Figure 1 shows thethree major layers of functionality in contact centers: 1)applications, 2) contact center middleware, and 3) voice and datanetworks.

Core TopicEnterprise Networking: Voice Applications

Key IssueHow will voice technologies andarchitectures evolve?

Strategic Planning AssumptionsBy 2005, all new large call center (morethan 150 agents) deployments will definefunctional layers as the basis for newcomponent deployments (0.7 probability).

Through 2006, large call centers (more than150 agents) that do not use the layeredapproach to call center design will expend30 percent additional effort and cost whenadding functionality (0.7 probability).

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The voice and data networking layer: This layer, shown at thebottom of Figure 1, provides the core physical transport, as wellas the logical connectivity, between applications, platforms, sitesand individuals. Virtually all contact centers now incorporateelements from circuit-switched voice networks and data networksof various sorts, including those based on TCP/IP. Enterpriseswill continue to develop voice and data evolution andconvergence plans that match their own needs. In most cases, itis critical that the planning of this layer of functionality be allowedto evolve at its own pace, independent of specific applications.When application needs change, or conversely, when networkoptions change, the changes can be implemented with minimaleffect on the rest of the enterprise.

The middleware layer: This layer provides the infrastructure thatis closely associated with voice calls, including automatic calldistributor (ACD), computer-telephony integration (CTI) andinteractive voice response (IVR) systems, as well asinfrastructure closely associated with Internet contacts, such ase-mail, chat and Web collaboration servers. As contact centersshift toward a software-based component architecture, it is usefulto view the middleware in terms of two sublayers: the lowerchannel-specific servers and a separate upper layer of n-tieredsoftware services. The channel-specific servers are responsible

Figure 1Layers of Functionality

ApplicationLayer

Network Layer

Channel-SpecificServers

N-TierSoftware Services

Middleware Layer

MOM

"Outdialer"Voice Portal

PBX/IP-PBXACDIVR

Text Chat

E-Mail

Collab. BrowsingERMS

WirelessVoice MailFaxInstant Msg.

Voice and Data Layer

Front-Office and Back-Office Applications

Queue Mgmt.RoutingRules

Agent Skills & Status

Reporting

Desktop Access

Benchmarks

Customer-Relationship-Enabling LayerMessaging

Workforce Mgmt.Workflow

Q&A

Analytics

Data Store

CTISOAP

LegendACD Automatic call distributorCTI Computer-telephony integrationERMS E-mail response management systemsIVR Interactive voice responseMOM Message-oriented middlewareSOAP Simple Object Access Protocol

Source: Gartner Research

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for interacting directly with a voice network or directly handlingdata networking protocols. In the past, call centers investedheavily in server-specific functions at this layer, especially ACDsand IVRs. Although this was necessary to achieve theconnectivity required, these servers were closely tied to theirunderlying physical connectivity and were often hardware-dependent, making them inherently less flexible. The softwareservices sublayer provides functionality used by multiplechannels or multiple sites. Investments at this layer can remain inplace even if the underlying physical servers are changed.

As contact center functionality moves to open software servers,the functionality shifts out of the channel-specific servers and intothe open contact center software servers sublayer. This enablesincreased independence of the contact center operations fromspecific underlying channels. It also allows enterprises to provideconsistent customer treatment, based on business rules, acrossall channels. These functions often are incorporated into auniversal queuing engine that performs multichannel queuing,routing and reporting. This independence enables contactcenters to make changes to the underlying networking layerwithout affecting the center's business operation. For instance, acenter can change from a circuit-switched ACD to one based ona Voice over IP architecture with fewer changes to its businessrouting rules. In another example, this tiered approach can befound in IVRs where the functionality that used to reside in asingle vertically integrated hardware/software system is nowshifting to lower-level VoiceXML interpreters and higher-levelvoice application servers. A key change in the services layer isthe use of message-oriented middleware (MOM) such as BEASystems' Tuxedo or IBM BQM, and the use of Simple ObjectAccess Protocol (SOAP). These approaches enable services tobe more loosely coupled with the applications they support.

The application layer: This layer encompasses front-office andback-office functionality, and also includes the server anddesktop portions of an application. It is at this layer thatapplications are most closely associated with customerrelationship management strategy functions. Figure 1 outlinesanother important group of contact-center-specific applicationlayer functionality: the customer-relationship-enabling layer.These are applications that are directly tied to managing thecontact center operations and ensuring the quality of thecustomer relationship. These include workforce management,quality assurance, analytics and audio mining, as well as others.Often these applications are operated independently of theunderlying contact center middleware. However, increasinglevels of integration with each other and with underlyinginfrastructure are likely over time.

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Enterprises should use these layers as a general guide ratherthan as a strict rule. Using these layers will assist with planningmigrations and architectures by reducing dependencies andclarifying functionality within a layer. However, enterprises shouldnot expect that all dependencies will be eliminated. Additionally,there are reasons why enterprises will wish to have specificvertically integrated solutions; for instance it is often easier tobring in a new contact technology as a single vertical stack.However, in this case, enterprises should be aware that greaterinter-layer dependencies cause downstream integration andmigration problems.

Bottom Line: Contact centers are in a constant state of change,and enterprises should use a layered approach to planning andevolution. The layers outlined allow each broad functional area toevolve independently. Without this layered approach, enterpriseswill find that their options will be more limited and the cost ofchange higher over time.

Acronym KeyACD Automatic call distributorCTI Computer-telephony

integrationIVR Interactive voice responseMOM Message-oriented

middlewareSOAP Simple Object Access

Protocol