SIP User AgentsSIP User Agents

SIP.edu WorkshopBCIT, Burnaby, British Columbia

Ben Teitelbaum <ben@internet2.edu>

SIP.edu WorkshopBCIT, Burnaby, British Columbia

Ben Teitelbaum <ben@internet2.edu>

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OutlineOutline

• Why UAs Matter• What they do or might do• Phyla• Hard phones• Soft phones• Mobile devices• B2BUAs• GWs and Tas• Media servers

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Quick SIP Review:REGISTER*

Quick SIP Review:REGISTER*

200 - OK

REGISTER: sip:dbaron@MIT.EDU

401 - Unauthorized

User B MIT.EDUMIT.EDU

Registrar

REGISTER: (add credentials)

MIT.EDUMIT.EDU

Location

sip:dbaron@MIT.EDU

Contact 18.18.2.4

* Slide courtesy of Dennis Baron

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Quick SIP Review:INVITE*

Quick SIP Review:INVITE*

INVITE: sip:dbaron@MIT.EDU“Calls” dbaron

@MIT.EDUINVITE: sip:dbaron@18.18.2.4

100 - Trying

180 - Ringing

Rings180 - Ringing

200 - OK Answers

200 - OK

ACK

BYEHangs up

200 - OK

User A

User BMIT.EDUMIT.EDU

Proxy

Talking TalkingRTP

* Slide courtesy of Dennis Baron

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User Agents: Architectural RoleUser Agents: Architectural Role

• User Agent Client (UAC) ≈ User Agent (UA)• Architecturally significant role• Global SIP “ecosystem” is a balance of

campus/enterprise infrastructure and P2P• Far more P2P than PSTN• SIP pushes functionality out to end-points

• Signaling after communication established• Media transport and negotiation• PBX-style “features”• NAT traversal• …

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User Agents: User ExperienceUser Agents: User Experience

• Personal communications is personal• UIs matter hugely• Usability (How do I do x?)• Ergonomics (Does it feel good in my

pocket?)• Style (Hello Kitty SIP phone, anyone?)

• Can campuses can stay out of the SIP UA business, just as most of us are out of the MUA business?

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User Agents: Edge InnovationUser Agents: Edge Innovation

• P2P nature of SIP should support forklift-free path forward• Just as IP has provided edge-enabling connective

network infrastructure, SIP will provide edge-enabling connective applications infrastructure

• Points of possible P2P innovation• New codecs (some baseline LCD needed)• SIP extensions (e.g. SIMPLE)• New features (e.g. CPL, personal IVRs, P2P

conferencing)

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UA FeaturesUA Features

• UI or form factor (for devices)• Codec support (G.711, G.729, iLBC, Speex)• Encryption (SRTP)• NAT traversal• Asserted identity• PBX feature set (hold, transfer, MWI, mute,

DND, conferencing)• DNS, ENUM, registration

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Hard Phones: Low EndHard Phones: Low End

• Basic functionality

• Zero, one or two line display

GrandstreamBudgeTone 100

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• Fancier displays

• High-quality speakerphones

• Directory integration

• Programmability

• Lots of buttons

• POE

Snom 360

Cisco 7960

Hard Phones: Mid-RangeHard Phones: Mid-Range

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Hard Phones: High EndHard Phones: High End

• Video

• Style

• Status

Motorola Ojo

Some Crazy Thing

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Soft PhonesSoft Phones

• Software running on a PC or laptop

• UI options• Picture of a phone• Contact list• Right-click application integration

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Softphone UI: a Picture of a PhoneSoftphone UI: a Picture of a Phone

Pingtel Instant Expressa

• Familiar interface• But on a PC, does

this make sense?!• Some of these feel

like HW simulators for firmware developers

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Softphone UI: Contact ListSoftphone UI: Contact List

Wave Three Software’s SessionMicrosoft Windows Messenger

• Presence-centric UI• Borrowed from AIM, etc.

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Some of BothSome of Both

Xten eyeBeam

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Mobile DevicesMobile Devices

Pulver WiSIP

HP iPAQ

Music + CommunicationComing Soon...

Vocera Wearable

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B2BUAsB2BUAs

Jasomi PeerPoint

Netrake nCite

• NAT-traversal• CALEA• Bad, bad, bad.

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Gateways and TAsGateways and TAs

Sonus GSX9000Grandstream HandyTone ATA-286 Cisco 2600 Series

*Small HugeMedium

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Media ServersMedia Servers

• IVRs

• Conference servers

…

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P2P SIPP2P SIP

• Skype phenomenon has caused rethinking of need for proxy/registrar

• 100% P2P SIP is on the way• Basic idea: clients REGISTER to join DHT,

which is then used for routing• Chord for DHT

• http://www.p2psip.org/

Node ANode-ID 023

Node BNode-ID 245

Alice’s NodeNode-ID 503

1. REGISTER

302 Node B

2. REGISTER

200 OKAlice-> Alice’s Node

Node CNode-ID 520

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Can Campus/Enterprise SIP Compete?Can Campus/Enterprise SIP Compete?

• <editorial>• With proper plumbing to campus IT

assets and freedom for P2P edge innovation, I believe it can

• If we lock down VoIP (e.g. deployed as a PBX replacement strategy) and not allow edge innovation, campus SIP will lose out to consumer services

• </editorial>

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