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Chapter 6 Server
X2002 User’s Guide
147
6.11.1 How the Peer-to-Peer SIP Connection Works
The following is a basic explanation of how the X2002 creates a peer-to-peer SIP
connection between two IP phones on the same subnet.
1
The first phone (
A
) sends an invite for the other phone to the X2002. This invite
includes its IP address and which codecs it can use.
2
Next, the X2002 accepts the invite on behalf of the second phone (
B
) and sends
an acknowledgement back to
A
.
3
The X2002 sends an new invite to
B
. This invite includes the X2002’s IP address
and the codecs it has in common in with
A
.
For example, if
A
says it can use the G.723, Speex, and GSM codecs but the
X2002 is set to G.723, then the X2002 lets
B
know that only the G.723 codec is
available for the telephone call.
4
When
B
accepts the invite from the X2002, it sends back an acknowledgement.
The X2002 has now received confirmation from both phones of their IP addresses
and an mutually agreed upon codec.
5
The X2002 sends out a re-invite to both
A
and
B
that includes both IP addresses
and the codec to be used. This allows the two phones to create a bridge directly
with one another. The X2002 then removes itself from the communication chain.
Note: If either phone A or B requests to use a feature specific to the X2002, such as
call parking or music on hold, the X2002 interrupts the direct communication
bridge and re-establishes control of the two SIP connections.
Figure 66
A Peer-to-Peer Example
Bridge
X2002
A
B
Summary of Contents for X2002
Page 2: ......
Page 24: ...Table of Contents X2002 User s Guide 24...
Page 25: ...25 PART I User s Guide...
Page 26: ...26...
Page 40: ...Chapter 2 How It Works X2002 User s Guide 40...
Page 99: ...99 PART II Technical Reference...
Page 100: ...100...
Page 124: ...Chapter 5 Network Deployment X2002 User s Guide 124...
Page 166: ...Chapter 7 Auto Provision X2002 User s Guide 166...
Page 170: ...Chapter 8 QoS X2002 User s Guide 170...
Page 248: ...Chapter 16 Click To Talk Group X2002 User s Guide 248...
Page 252: ...Chapter 17 Group Access Code X2002 User s Guide 252...
Page 304: ...Chapter 19 Auto Attendant X2002 User s Guide 304...
Page 312: ...Chapter 20 LCR X2002 User s Guide 312...
Page 346: ...Chapter 22 Call Services X2002 User s Guide 346...
Page 380: ...Chapter 25 Status Observation X2002 User s Guide 380...
Page 402: ...Chapter 27 Call Detail Record CDR X2002 User s Guide 402...
Page 410: ...Chapter 28 ACD Logs X2002 User s Guide 410...
Page 416: ...Chapter 29 Administrator Accounts X2002 User s Guide 416...
Page 424: ...Chapter 30 Diagnostics X2002 User s Guide 424...
Page 426: ...Chapter 31 X2002 User s Guide 426...
Page 446: ...Chapter 32 Remote Management X2002 User s Guide 446...
Page 448: ...Chapter 33 TFTP Management X2002 User s Guide 448...
Page 462: ...Chapter 35 License Control X2002 User s Guide 462...
Page 482: ...Chapter 36 Web Portal X2002 User s Guide 482...
Page 508: ...Chapter 39 Product Specifications X2002 User s Guide 508...
Page 548: ...Appendix C Legal Information X2002 User s Guide 548...
Page 562: ...Index X2002 User s Guide 562...