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VoIP at the University of Oregon The View from the Telephone Side. Dave Barta, University of Oregon dbarta@oregon.uoregon.edu. VoIP Applications Two Distinct Evaluations. Voip in the backbone OPX replacement Tandem networks Telephone switching systems to the desktop.
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VoIP at the University of OregonThe View from the Telephone Side Dave Barta, University of Oregon dbarta@oregon.uoregon.edu
VoIP ApplicationsTwo Distinct Evaluations • Voip in the backbone • OPX replacement • Tandem networks • Telephone switching systems to the desktop
OPX Replacement Locations • Oregon Institute of Marine Biology (OIMB) • 100 miles from Eugene in Charleston, OR • Pine Mountain Observatory • 200 miles east • Over a major mountain range • 19 miles from nearest paved road • Future locations in local area
OPX Replacement - OIMB • 2 analog ext. off UO PBX - 5 digit dialing • Trunk group in OIMB key system • Dial Access Code (DAC) + 5 digits • Tail End Hop Off (TEHO) in OUS Cities • LD Access • Rides US West frame relay T1 • $450/month • Relatively low traffic
OPX Replacement - OIMB (cont.) • Replaces one Off Premises Exchange line (OPX) @$250/month • No signalling except supervision • No compression (G.711) • Quality accptable (but noticeable difference) • 2 LEC service areas - GTE, USWest
OPX Replacement - Pine Mountain • Like OIMB except two phones instead of key system. • No OPX before - calls to campus LD. No access to dedicated LD services. • Served by T1 frame relay circuit dropped from microwave tower on same mountaintop.
OPX Replacement - Local Remotes • Rate changes creating advantageous climate • T1 @$300/mo. • DSL over 4-wire LADs @$48/mo., but possibly going to $200/mo. • OPX @$31.50/mo., but possibly going to $84/mo. • In use at staff homes • Contemplated for other off campus offices
VoIP to replace OPX is simple because: • Usually no DID (although fairly simple with E&M tie trunk interfaces) • No need for complex call accounting • No or simple voicemail requirements • Simple PBX translations • Voice bandwidth requirements minimal
VoIP in the OUS Tandem Network • Challenging • Interesting • Cost Effective (probably)
The Oregon University System voice network connects: • 3 semi-large universities: • UO, OSU, PSU • All in the Willamette Valley • 4 small regional universities: • WOU, SOU, EOU, OIT • Geographically remote • OHSU - Public corporation in Portland
OUS ETN history and culture • 1988 - Contract with AT&T • 8 PBXs - Sys 85-G2-G3 • Dorm phones for LD resale • Copper and multimode fiber backbones • Voicemail - Audix - Intuity • ETN network and NOC • 1992 - H.320 video and MCU • 1998 - Y2K upgrades to G3, Intuity, misc. systems • Intelcom Committee sets policy • Equivalent systems across OUS, with exceptions • Funding model subsidizes regional universities
OUS ETN consists of: • Multiple ISDN-PRI hubbed to OSU • AT&T SDN long distance from large universities w/ small schools using OSU SDN • Video MCU at OSU - multipoint H.320 video or voice and w/ upgrade H.323 gateway and multipoint • Shared CMS - ACD and trunking management statistics • Fault reporting - receives system alarms, filters based on severity, and pages support staff • NOC staff • Call accounting
ETN features: • 5-digit dialing between campuses - shared # plan • DCS - passes name info, answer and disconnect supervision • SDN access for regional universities • Networked voicemail - name, # in message header • TEHO - Tail end hop off in each metro area • H.320 video between schools and to MCU • Reliability and stability
Forces of Change: • Cost Factors • Long point-to-point T1s to EOU, SOU, OIT • 384K H.320 video and voice traffic forced T1 #2 • Opportunity factors • Available OWEN bandwidth in backbone • SDN rates dropping • LD market competition • Technological advances • Compression - Reliability • Features (signalling) - Standards
ETN Replacement Options: • ISDN-PRI SDN - Add SDN to regional schools and use it for LD, TEHO and (with QSIG) for all ETN functions • VoIP to some or all schools w/ or w/o QSIG, depanding on vendor solution • Hybrid Solution - VoIP in the Valley, ETN or SDN in the hinterlands
Major Assumption:All existing features will be maintained or improved
Challenges • Bandwidth limited on frame circuits to regional universities • At cheap frame price may be worth adding frame circuits just for voice except… • US West CIR unreliable • Support for DCS signaling just emerging • Cisco to support some sort of signalling soon • Lucent proprietary solution to packetize signaling information over IP network whether voice is IP or ETN
Other Issues • Call accounting - on-net/off-net pricing based on PBX trunk group, so not a problem • Video support • H.320 much easier with ETN network than SDN or 700 number option for schools without PRI trunking • Move to H.323 will help but H.320 still growing • Voice Quality - difference is noticeable, but meaningful?
Other Issues (cont.) • Control • Telecom is sole owner and user of ETN network (except for AT&T, US West, GTE, and PTI, of course) • Using OWEN introduces many more interested parties and we would, for now, be the only isochronous app. • SOEN/state politics - network ownership is a political issue which goes outside of higher ed. • Complexity - more hardware, more protocols, more people, multiple alarm platforms
Other issues (cont. again) • Installation cost • PBX cards • Router ports/cards • Possibly more SDN or frame circuits • Time and energy • Remote maintenance • PBXs don’t support IP access for maintenance and troubleshooting - modem or on-net EIA only • If/when IP maintenance access, security becomes an issue
Experimentation • Cisco solution without signalling • T1 from PBX to Cisco router at UO and OSU • Discrete trunk group with manual DAC access • QOS available but not necessary • Voice great at G.711, noticeable difference at G.729(a) • No fax or modem support • DID capability
Experimentation (cont.) • Lucent Internet Telephony Server (ITS) • Outboard NT Server w/ T1 interface to PBX • DID but no DCS • Good voice, fax support • No compression • Ping and measure delay on call setup and give busy if too much, but otherwise no QOS
Future Developments • Cisco to support signaling • We’re experimenting • Lucent • ITS replaced by inboard 3 slot card - G3V7 • 3 slot card replaced by one slot card - G3V8.1 • Support QOS via precedence bit - G3V8.2
VoIP to the DesktopWhat we have - What the users want • Lucent Definity G3 V7 PBX • 7,000 stations, 550 PSTN trunks, • 5 T1 to AT&T for SDN, TSAA, 0+ • 3 T1 to ETN network • Features Supported • Extensive alarm reporting • Call coverage off-net and back • The usual pickup, park, transfer, + 6-way conf.
PBX features (cont.) • ACD call centers w/ realtime, summary reports • Integrated and networked voicemail • Multiple sets from POTS to 36-button display • Supports wireless integration • Caller ID (# only) on digital sets and analog (v8.2) • Legacy applications - alarms, modems, faxes, emergency phones, elevator phones • ISDN-BRI
Experimenting with IP Phones • Purchased Selsius Trial Pack • 6 sets used consistently on campus • Sets to remote locations • One at OSU via Owen - worked fine • Took one to SLCC and used over congested commodity internet - that was cool and useful • OSU to try same trick with telecommuter in Phoenix - a potentially useful application. • Simple programming interface • Limited feature set • Lots of IP PBX rebooting • g.723(1) did not pass muster
Issues/obstacles to real implementation • Full feature set, array of telephone sets, and set cost • Redundancy/reliability in controllers and core routers • Distributed architecture means distributed backup power - $ and space • e911 - solvable at the expense of mobility • Voice quality - compressed voice IS different, but does it matter?
My opinion • Seriously viable in small locations • Reduced feature requirements • Consolidated closets so power not an issue • Usually not fully integrated with campus voicemail, etc. so not an issue • Price will decide • Soon a good option on a campus without an existing cable plant
Last few opinions • Wouldn’t want to be facing a PBX decision right now - cutting a large PBX is hard enough without it being a beta test • PSTN response important • IP or some packet approach would reduce expensive SONET gear • It’s time for compression • IP to PSTN breaks their pricing model to our advantage • Hybrid of traditional telephony, IP, wireless