SURFNET EXPERTISECENTRUM

IP-telephony in research networks: the

big picture

Klaas WierengaSURFnet ExpertiseCentrum bv

june 1999

klaas.wierenga@sec.nl

SURFNET EXPERTISECENTRUM

Outline• SURFnet and the SURFnet backbone

• Multimedia conferencing infrastructure

• Current activities

• Why IP-telephony

• The test

• Initial results

• Gigaport activities

• Conclusion

SURFNET EXPERTISECENTRUM

The SURFnet backbone

622 Mbit/s

155 Mbit/s

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MM Conferencing Infrastructure• Paradoxical movements in education

– collective --> individual– knowledge-intensive --> communication-

intensive

=> Tele-education

• Pilot: Open Education Environment

• Middleware components…..

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Current activities• Conferencing

• Groupware

• Streaming

• MCU’s

• Web-innovation

• Directories

• Searching and Indexing

• Caching and replication

• QoS (RSVP, Diffserv etc.)

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Why IP-telephony?• Universities: high bandwidths, bad equipment

• Students at home: low bandwidths, good equipment

=> common denominator is low bandwidth, bad equipment

• (Limited) technical improvements• Easy transition to richer communication means

• Everybody has a phone

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– delay– jitter– packet loss

SURFnet

gatekeeper

IP tel.

Workstation/PC

Gateway/router

Tel (PSTN/ISDN)

PBX

pc-pc

tel-tel

pc-tel

The test

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Components• Gateways

– Cisco– Radvision– Lucent– Clarent

• Gatekeepers– Ericsson– Radvision– Selsius (Cisco)– Clarent

• Terminals– Netmeeting, Vcon, Selsius (Cisco) phone

SURFNET EXPERTISECENTRUM

Test items (1)

• QoS guarantees

• Delay (<200 ms)

• Jitter

• Networkload

• Authentication, authorisation

• Management

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Test items (2)• “MOS” (Mean Opinion Score)

– call setup (< 4 sec)– stability (0% disconnects)– completion (> 95%)– audio quality– echo

• Scalability

• Interoperability of gateways and gatekeepers!!!!

• Interfacing with PBX

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Initial results (1)

• Interfacing with PBXs very bad

• Interoperability gateways reasonable

• Interoperability gatekeepers bad

• Delay and jitter over SURFnet

dominated by codec and terminal

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Initial results (2)• Authentication and authorisation still suboptimal

• Quality of speech can be good

• Integration with other applications is good

• NRN shouldn’t operate gateways?

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GigaPort

‘Speed provides the one genuinely modern pleasure’

Aldous Huxley

• Access networks• Backbone• QoS• Generic Services• Communication Applications

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Conclusion

• Integration with other applications

instead of ‘cheap minutes’

• NRNs should concentrate on the infrastructural part of IP-telephony

• Interoperability is key factor for

NRNs