Dennis Baron, July 20, 2005

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Architecture Dennis
Baron July 20, 2005
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SIP.edu

• Goals
• Grow SIP connectivity in Internet2
• Increase value proposition for end-user SIP
  adoption
• Promote convergence of voice and email identity
• Low entry-cost means for campuses to...
• Provide a useful service
• Get their feet wet with SIP
• Means
• Publishing cookbook with several alternative
  recipes
• Obtaining corporate sponsorship and promotional
  pricing

3
Why Phone NUMBERS?

• Users should not be burdened with device
  addresses, when its people they really care
  about
• Addresses should be mnemonic and empower
  enterprises to manage the identities of their
  users
• sipdbaron_at_mit.edu
• Its time to put E.164 phonenumbers behind us!
• A.G. Bell did not say

1-617-252-1232, come here. I need you!
4
SIP.edu Architecture (Phase 1)
SIP User Agent
INVITE (sipbob_at_bigu.edu)
DNS SRV query sip.udp.bigu.edu
bigu.edu
SIPProxy
SIP-PBXGateway
PRI / CAS
INVITE(sip12345_at_gw.bigu.edu)
PBX
telephoneNumberwhere mailbob
Bob's Phone
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SIP.edu Architecture (Phase 2)
SIP User Agent
INVITE (sipbob_at_bigu.edu)
DNS SRV query sip.udp.bigu.edu
If Bob has registered, ring his SIP phone Else,
call his extension through the PBX.
bigu.edu
INVITE (sipbob_at_207.75.164.131)
REGISTER(Contact 207.75.164.131)
Bob's SIP Phone
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SIP.edu Call Flow Example

• SIP DNS lookup for MIT.EDU points to SIP proxy
• Sends INVITE to bob_at_mit.edu to proxy
• SIP proxy checks MIT directory
• Maps call to PBX extension eg. 37669_at_mit.edu
• SIP proxy checks dial plan
• Routes call to PBX gateway
• PBX rings phone

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SIP.edu Configuration
Campus Network
DNS Server
LDAP Server
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DNS SRV Lookup
DNS SRV
Campus Network
DNS Server
LDAP Server
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SIP INVITE
SIP
Campus Network
DNS Server
LDAP Server
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LDAP Lookup
LDAP
Campus Network
DNS Server
LDAP Server
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Call Sent to PBX Gateway
SIP
Campus Network
DNS Server
LDAP Server
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Media Stream via Gateway to PBX
RTP
Campus Network
DNS Server
LDAP Server
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SIP.edu Configuration
Campus Network
DNS Server
LDAP Server
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SIP to PBX and PSTN Calling
Campus Network
DNS Server
LDAP Server
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PBX and PSTN to SIP Calling
Campus Network
DNS Server
LDAP Server
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Workshop Configuration
sipedu-gw.tamu.edu
Texas AM
LDAP Server
sipedu-univ10.tamu.edu
DNS Server
Campus GW
...tamu.edu
Toll GW
195.91.160.4
PBX
PSTN
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Workshop Configuration
sipedu-gw.tamu.edu
Texas AM
LDAP Server
sipedu-univ10.tamu.edu
DNS Server
Campus GW
...tamu.edu
Toll GW
195.91.160.4
PBX
PSTN
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Workshop Configuration
sipedu-gw.tamu.edu
Texas AM
LDAP Server
sipedu-univ10.tamu.edu
DNS Server
Campus GW
91 10-digits
...tamu.edu
Toll GW
195.91.160.4
PBX
PSTN
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Workshop Configuration
sipedu-gw.tamu.edu
Texas AM
LDAP Server
8 4-digits
sipedu-univ10.tamu.edu
DNS Server
Campus GW
...tamu.edu
Toll GW
195.91.160.4
PBX
PSTN
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SIP.edu Just do it! Questions?