Migrating from Centrex to IP Telephony at Penn

ISC Networking & Telecommunications

Migrating from Centrex toIP Telephony at Penn

Deke KassabianUniversity of Pennsylvania


About Penn• University of Pennsylvania is a private, Ivy

League university in Philadelphia• 20,000 students (undergraduate & graduate)• 4,000 faculty & 13,000 staff• 250 buildings• 30 RDPs (telephony points of presence)• 23,000 phone lines & 41,000 IP addresses


Some Background

• Networking & Telecom organization merger in 2000, with full integration over the course of the following four years

• Environment: Centrex +Penn-owned cable

• 4 exchanges, 1 area code

• 5 digit dialing on campus


Business Drivers

• Aging voice cable infrastructure and voice mail components

• Moves/adds/changes – inflexible and costly

• Wish to increase operational efficiencies

• Prefer vendor independence

• Prefer open standards

• Prefer open source


The Organization• Consciously avoided silos through integration of

Data/Voice staff with similar jobs– Operations– Engineering, New Service Development– Finance and Billing– Customer Service

• Some staff reductions took place• New organization is fully integrated, and increasingly

well cross-trained• New organization also includes Video group


Considering our Next Steps

• Wanted to make a business move to deliver highly flexible and cost-effective telephony with a longer horizon

• Had a track record of success with open source communications software

• What would it take to seriously pursue this approach?


The Breakthrough

• Project launch meeting with managers & team leads

• Identified biggest issues

• Committed significant local staff resources

• Hired project manager


Project Teams

Steering Committee

Technical Process BusinessFacilities

Network Architecture

Application Architecture

Telephony Architecture

InstallationsOperations

IntakeSupport

Billing

Provisioning

Communications


Internal Pilot Campus Pilot

• Roll out production pilot within our own department

• Structure installations to be cookie cutter• Train Centrex staff to be VoIP specialists• Start punch-list management• Continue to evaluate and adjust


Challenges• “Recruiting” pilot customers

– That fit the service profile– That are in a suitable building– That are willing to work with a pilot, providing

useful feedback• Supportable Handsets

– Single line & multi line sets – Multiple Manufactures


Open Source Strategy• Avoid over-customization

– Use existing functionality where possible– Maintain active relationship with developers– Try to get any essential changes built back into

mainline code

• Notable Asterisk customization– IMAP access to voice mail message store for true

unified messaging – Penn developed extension to Asterisk, likely to be

included in 1.4 with Summer 2006 release


Current State of Service• Production-grade

– Redundant servers, gateways and PRIs

– Single-line features, email/voicemail integration

– 911 support equal to legacy system

• layer 2 QoS, separate VLANs & subnets

• Full service- installation, support & billing


VoIP Topology


Campus-wide Pilot Rollout

0

200

400

600

800

1000

1200

Jul-05

Nov Jan Mar May Jul-06

Jul-07

VoIP PilotVoIP Actual


Success

• 400+ subscribers, 500 scheduled by June

• Network Architecture Team

• Process re-engineering

• Site/server failover recovery

• Open-source software (SER, Asterisk)


Penn iPhone Web Services (Phase 1.0)

Self-serviceVoice mail

Change Email

Password

Do Not Disturb

Call Forward

Reject Anon.

Blocked Caller ID

More . . .




Lessons Learned• Pilot one technology at a time (open-source vs. in

house commercial vs IP centrex)• Deliver service components in phases, to

compatible customers• Create/maintain a voice development environment• Use Centrex staff to manage VoIP installations• Pilot support services & involve customers


• Make project a priority across the organization• Deliver a production pilot• Cross-train staff, and allow time for adjustment• Augment staff with consultants in key areas• Technology is evolving: let current state determine

project scope

Recommendations


Migrating from Centrex to IP Telephony at Penn

Deke KassabianUniversity of Pennsylvania

Migrating from Centrex to IP Telephony at Penn

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