Bridging the IP Migration Gap

Computerworld -

Mergers, acquisitions and the convergence of emerging technologies have resulted in a dilemma for companies, both big and small. The problem stems from the lack of transparency across heterogeneous communication systems and technologies. This lack of transparency and/or interoperability can include systems purchased from the same manufacturer depending on the time of purchase and the particular models.

As companies look to add IP telephony into their communications network, they are faced with making decisions that can be disruptive and costly. Depending on the existing infrastructure, a company's strategy could include a complete system replacement, upgrade or migration approach such as:

• Telephony-enabled LAN: A pure packet-switched system that requires forklift replacement of traditional private branch exchanges.


• IP-enabled PBX: A station-side gateway that allows IP phones to be connected to a traditional PBX.


• Converged systems: A hybrid that uses a combination of circuit and packet switching to provide a migration path for legacy infrastructure.

Mixed Systems
With a mixture of systems and technologies, IT managers could be dealing with any of these connectivity issues:

• Handing off calls from one system to another while maintaining calling party information so that it can be routed properly. Although QSIG, a signaling standard, will resolve some of these issues, it's expensive and sometimes not available for all of communications systems.


• In some scenarios, operators, supervisors and assistants are unable to "see" a user's extension status to redirect, pick up or forward calls ringing at a coverage point.


• Disparate voice-mail systems that were purchased to work with a specific manufacturer's telephone system can create call completion issues for users and system operators.


• Setting up and tearing down conference calls is compounded when several of the participant's extensions reside on different systems. The conference coordinator must know which digit strings to enter based on how connectivity is provided to each system.

Although the forklift approach resolves all of these issues, it is sometimes not feasible or practical to rip and replace all systems at once. Therefore, during the transition period, which could last two to three years depending on the magnitude of the project, overall staff productivity suffers due to the lack of a cohesive communication infrastructure.

A solution to this problem would be to make use of presence and call control software that will allow systems to coexist while the migration plan is implemented. This will provide all users with a desktop interface that spans the enterprise so that the migration is transparent to all users, eliminating many issues users face in a mixed environment.

What Is Presence?

Presence has become an industry buzzword with the rollout of instant messaging and single in-line package-based products. Unfortunately, traditional technologies such as those found in corporate telephone systems have been left behind and thus aren't included in the presence-based products being developed. What's needed is technology that addresses the issues related to this multibillion-dollar installed base of enterprise telephony systems and provides a clear path for companies to strategically plan their migration from the old to the new without compromising their internal communications infrastructure.

Presence-based software enables the user to know where people are, what devices or services can be used to communicate with them, and the real-time status of those devices (for example, on hook/off hook, connected, available, online, away and so on). This information is collected, then stored and updated in a real-time state engine and made available to other users across the enterprise.

Note that presence isn't exclusive to any one technology or limited to an instant messenger "buddy list." To obtain the full value from this technology, presence-based products must be capable of monitoring every conceivable type of communication device that an individual could use. This includes, and should not be limited to, traditional telephone systems, home telephones, cell phones, PDAs, desktop and portable computers, and other network appliances.

Real-time information is collected by simultaneously monitoring the state of every communication device in use across the enterprise. Interfaces such as TAPI, TSAPI, CSTA, SIP, WAP or proprietary connections provide events that are used to update the status of these monitored devices. The updated state changes are then made available to enterprise users facilitating communications between employees and customers.

Adding call control into this model enhances the overall value of presence-based applications by expediting the user's ability to contact the desired party by simply clicking a button. Call control software enables the user to control the operation of a communication device (answer, hang-up, dial, hold, transfer, conference and so on). With a knowledge of presence, a user could initiate a call to the intended party by pressing a command key or through spoken commands if voice recognition has been deployed.

How Presence and Call Control Can Help

Applications embedded with presence and call control functions are able to overcome many of the problems seen when an organization has multiple locations with an assortment of telecommunication systems or is in the process of migrating to IP telephony. These empowered applications can bridge the gaps that disparate systems and technologies create.

By simultaneously monitoring and displaying the real-time state of an individual's extension, mobile device and IM presence, a user can quickly identify how to best contact a co-worker. By embedding third-party call control into the application, digit strings needed to process the call to the requested party's extension are seamless. Operators can quickly process calls across a disparate enterprise without knowing how the call should be routed. By simply knowing that the party's communication device is available, the operator can initiate a transfer using a supervised or unsupervised approach as if on the same system. The displaying of IM status provides the operator with an alternative means of contacting the requested party, notifying them of a call holding.

If unavailable, the operator can offer to immediately transfer the caller to the requested party's voice mailbox. Once again, with the click of a button, the application automatically inserts the appropriate digit strings needed to complete the transfer regardless of the voice-mail system that the extension is connected to. The transfer is immediate, avoiding the need to ring the party's telephone enable to invoke the extension's call-forwarding parameters.

Supervisors and executive assistants can also provide call coverage for key personnel. Embedding the presence and call control technology into existing contact management applications, organizations can improve employee-to-employee and customer-to-employee communications. Frequently used applications, such as e-mail and CRM, could provide employees with a visual display of the presence and availability of everyone's communication device across the enterprise as well as displaying pop-up messages on an incoming caller's record and providing automatic dialing.

The use of presence and call control-based applications provide powerful productivity tools that can help make disparate systems and technologies work better together while allowing organizations to adopt a migration strategy that's transparent to customers and staff.

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