The document discusses Session Initiation Protocol (SIP) and provides examples of how SIP is used to set up voice and video calls between two endpoints. It explains the different SIP messages used - INVITE, OK, ACK, and shows how SIP establishes a voice or voice/video "stream". It also discusses SIP trunking, SBCs, codecs, QoS, NAT and security considerations. The last sections provide an overview of SIP certification through The SIP School and some example questions to ask an ITSP regarding their SIP offerings and interoperability.
6. Session Initiation Protocol - INVITE
1002
1002 1003
1003
Call 1003 Want to talk? SIP
SIP
From: ‘Bob’ <sip:1002@sipbiz.com>
To: <sip:1003@sipbiz.com>
Hold Video Hold Video
Hold Video
SDP Hold Video
11 22 33 11 22 33
Audio Codec – G711 or … Audio Codec – G729
44 55 66 44 55 66
77 88 99 77 88 99
** 00 ## ** 00 ##
7. Session Initiation Protocol – 200 OK
1002
1002 1003
1003
Call 1003 Want to talk? SIP
OK
SIP
From: ‘Bob’ <sip:1002@sipbiz.com>
To: <sip:1003@sipbiz.com>
Hold Video Hold Video
Hold Video
SDP Hold Video
11 22 33 11 22 33
Audio Codec – G711 or … Audio Codec – G729
44 55 66 44 55 66
77 88 99 77 88 99
** 00 ##
SIP 200 OK ** 00 ##
SIP
From: ‘Bob’ <sip:1002@sipbiz.com>
To: <sip:1003@sipbiz.com>
SDP
Let’s use G711…!
8. Session Initiation Protocol – ACK
1002
1002 1003
1003
CallCall
On 1003 ACK SIP
On Call
with 1003 with 1002
SIP
From: ‘Bob’ <sip:1002@sipbiz.com>
To: <sip:1003@sipbiz.com>
Hold Video Hold Video
Hold Video
SDP Hold Video
11 22 33 11 22 33
OK, G711 it is….!
44 55 66 44 55 66
77 88 99 77 88 99
** 00 ## ** 00 ##
Voice ‘Stream’
9. Session Initiation Protocol – Video?
1002
1002 1003
1003
On Call Support Video? SIP
On Call
with 1003 SIP with 1002
From: ‘Bob’ <sip:1002@sipbiz.com>
To: <sip:1003@sipbiz.com>
Hold Video
SDP Hold Video
Hold Video Hold Video
Audio Codec – G711, G729
11 22 33 11 22 33
Video Codec – H.264,H263,H261
44 55 66 44 55 66
77 88 99 77 88 99
** 00 ##
SIP OK ** 00 ##
SIP
From: ‘Bob’ <sip:1002@sipbiz.com>
To: <sip:1003@sipbiz.com>
SDP
Let’s use G711 and H.264
Voice and Video ‘Streams’
13. SDP SIMPLE
INFO
Load
Balancing
P2P
SIP
3261 REFER
SIP
Routing
With ENUM
Overload RTP for
Control SIPREC
14. The road to compatibility
344
344 Should
475
475 Can
May 381
381
Option
144
144
3261
15. Cookie RFC
Cookie RFC
Flour
Flour
Bicarbonate of
Bicarbonate of
soda
soda
Salt
Salt
Butter
Butter
Caster sugar
Caster sugar
Soft brown
Soft brown
sugar
sugar
Vanilla extract
Vanilla extract
Eggs
Eggs
Dark chocolate
Dark chocolate
Raspberry Jam
Raspberry Jam
Coconut
Coconut
28. Measure = 10 Trunks please
Voice = G.711 @ 90Kbps
Pipe = 10 x 90Kbps = 900Kbps
If using a 2Meg link
That’s ~ 44% for VoIP and the
rest for Data – Fully loaded…..!
29. Measure = 10 Trunks please
Voice G.711 @ 90Kbps
Video H.264 approx. 250Kbps (min)
Pipe = 10 x 340Kbps = 3.4Mbps
If using a 2Meg link, oops!
35. Let’s leave the video this
Let’s leave the video this
time
time
L7 SIP ~ 192.168.1.1 L7 SIP ~ 192.168.1.1
77.128.13.88
L3 IP ~ 192.168.1.1 L3 IP ~ 77.128.13.88
??
?
L7 SIP ~ 192.168.1.1
77.128.13.88
L3 IP ~ 77.128.13.88
36.
37. What?
ITSP
Network
Your PBX
REGISTER
Client X
SIP Registrar
10 Trunks
Authentication
G.711
Authorization
Call Rates
Encryption
Voice – YES
• Signalling
Video -Traffic
• Voice NO
43. PSTN
ITSP Offerings
We need have our ‘old’ numbers please?
Can we some more DDI’s
PBX
Router That’s us
No course!
Of problem
Can I have a ‘London’ number?
PSTN
44. PSTN
ITSP Offerings
We need more lines more our marketing push!
Thwarted
PBX
SHA //TLS //SRTP
SHA TLS SRTP
Router I’ll do that!
I can do that via our Web Interface
PSTN
52. SIP
SSCA®
SIP School Certified
Associate
SIP SSMP™
SIP Sales and Marketing
Professional
53.
54. The Telecommunications Industry
Association (TIA), the leader in advocacy,
standards development, business
development and intelligence for the
information and communications
technology industry, has officially endorsed
‘The SIP School’ as the provider of choice
for training and certification for Session
Initiation Protocol (SIP).
Hurricane Sandy and Verizon, not replacing Copper lines but just using as a chance to cut the cord.!!!!!! Comment on this Companies that rely on PSTN Gary Audin and Stuff that needs Analogue Fax!!! AT&T ask the Federal Communications Commission to create a timetable to shutdown the analog PSTN phone system in the United States. AT&T explains that “maintaining two networks - IP and PSTN is retarding the deployment of the newer broadband IP network”. Teliasonera – 2 years SO…. It’s happening then…. No going back…………………………… AT&T has asked the FCC to create a timetable that would allow the company to shut down its analog public switched telephone network (PSTN). AT&T said doing so is the only way to meet Congress' goal of covering all Americans with broadband services as more investment would flow to its IP-based initiatives. "That transition is under way already," AT&T wrote to the FCC. "With each passing day, more and more communications services migrate to broadband and IP-based services, leaving the public switched telephone network (PSTN) and plain-old telephone service (POTS) as relics of a bygone era.“ AT&T argues that having to maintain and invest in two networks--broadband and the PSTN--means Congress' goal won't be met efficiently or timely. The company said that while 90 percent of Americans have access to broadband services, reaching that last 10 percent would require an investment of about $350 billion. Meanwhile, AT&T continues to struggle with its own 3G network because of data hungry smartphone users. "Due to technological advances, changes in consumer preference and market forces, the question is when , not if , POTS service and the PSTN over which it is provided will become obsolete," AT&T wrote to the FCC. AT&T also said that less than 20 percent of Americans rely exclusively on POTS for voice service, while 25 percent of households have abandoned POTS. It noted that some 700,000 lines are being turned off each month. AT&T outlined steps for shutting down the PSTN and wants the FCC to swiftly follow them. AT&T's letter was in response to a public query from the FCC seeking comment on how the nation should migrate from circuit-switched networks to all-IP voice networks.
Let’s do the maths….
So if you are supplying a connection for your client, you need to ask these questions…