Transcript Presentation

SIP-based VoIP Deployment in
Taiwan
Speaker: Dr. Quincy Wu
([email protected])
National Telecommunications Program Office
October 16, 2003
1
Topology Map of TWAREN
(Taiwan Advanced Research & Education Network)
SINICA
NCU
NCTU
NTU
Taipei
NTHU
Hsinchu
NCHU
NCNU
Taichung
NSYSU
Eastern Broadband (STM-64)
Chunghwa Telecom (10GE)
Chunghwa Telecom (5 G)
Core nodes
CCU
NCKU
NDHU
Tainan
Dual circuits from two vendors
form the physical backbone to
guard against failures.
2
NTP VoIP Platform
3
Year 2003
NTU
• Five SIP-reachable
Universities
NTHU
NCTU
NDHU
NCKU
– National Taiwan University
– National Tsing Hua University
– National Chiao Tung
University
– National Cheng Kung
University
– National Dong Hwa University
• PBX phones and SIP-based
softphones are all “SIPreachable” in each campus.
4
SIP UA Addressing
• SIP URI
– [email protected]
– [email protected]
• E.164 number
– 886-944-021021 (for international users)
– 0944-021021 (for domestic users)
• This number will be transformed (internally by the call server)
to SIP URI sip:[email protected]
• Each call server maintains a “routing table” and forwards an
INVITE request to its target according to the prefix.
5
E.164 vs. SIP URI
Problem:
How to Address (or Locate) a User in IP Telephony World or
PSTN/VoIP Integrated Network ?
ENUM is a Mechanism to Translate
an E.164 Number into A List of URI (Service@host)
So that An IP User Can be Accessed by E.164 Number.
E.164 Number
ENUM
Mechanism
URI (Service@Host)
Domain Name System (DNS)
 RFC2168, “ Resolution of Uniform Resource Identifiers using the Domain Name System”, June 1997.
 RFC 2916, “E.164 number and DNS”, September 2000.
 RFC 2915, “The naming authority pointer (NAPTR) DNS resource record”
6
Taiwan ENUM Trial
NTU
Tier 1
NS(e164.tw)
SIP
TWNIC
Proxy
Tier 2
NS
IP Phone
Tier 2
Registrar
Softphone
NCTU
SIP
Proxy
IP-PBX
SIP
RTP
Softswitch
SS7
PSTN
7
Conclusion
• By establishing a nation-wide VoIP testbed, NTP
wishes to promote the convergence of voice and
data services and encourage advanced researches
in Taiwan.
• With the joint-effort from ENUM Trial Project
Taiwan, all these SIP users can be reached from
PSTN phones by dialing E.164 numbers, and vice
versa. 100,000 numbers are allocated for this trial.
• SIP coverage in this year is approximately 50,000
users. NTP plans to double the coverage in 2004,
and hopefully extend the connectivity with
SIP.edu project in Internet2.
8
Appendix: Softswitch Architecture
• Softswitch: Emulating Circuit Switching in Software
PSTN
Local
Switch
STP
SG
IN/SCP
SS7
Network
PSTN
Local
Switch
SG
IP Network
MGC
MGC
Trunk
Gateway
Trunk
Gateway
RTP Streams
9000
Personalized VoIP
Service System
IP Phone
Application Server
9