1. Expanding Internationally
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s si
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Challenges & Solutions
Jonas Borjesson
Tech Lead – All things SIP
jonas@twilio.com
@borjessonjonas

2. Challenges
● Signaling
● Establishing the call
● Connecting/interop with carriers around the world
● Media (Audio Quality)
● Delay
● Jitter (drop-outs)
● Strange audio artifacts
● Numbering
● People are used to certain number series
● Different laws around the world
jonas@twilio.com
@borjessonjonas

3. Latency
● Make sure that media takes the shortest route
possible – no matter where the users reside
● Less latency
● Minimizes risk for jitter
jonas@twilio.com
@borjessonjonas

4. Things can change!
● Have to be capable of changes mid-call
jonas@twilio.com
@borjessonjonas

5. Deploy Media Capabilities
Everywhere
● Essentially: carrier
● B2BUA:s for traffic
● Relays for media
lb
● Note:
● Carrier is not re-invited b2bua
● Media is not p2p
Why not???
1 3
2
Signaling
Media jonas@twilio.com
@borjessonjonas

6. Carrier Interop + Media Features
● In our experience:
● Carriers do not in general support re-invites
● Transcoding between carriers
also
● Users...
● wish to record the audio
● use DTMF for controlling the call (hangup-on star)
jonas@twilio.com
@borjessonjonas

7. THE END
jonas@twilio.com
@borjessonjonas