RFC 3261 SIP: Session Initiation Protocol June 2002
8.2.6 Generating the Response ............................. 49
8.2.6.1 Sending a Provisional Response ...................... 49
8.2.6.2 Headers and Tags .................................... 50
8.2.7 Stateless UAS Behavior .............................. 50
8.3 Redirect Servers .................................... 51
9 Canceling a Request ................................. 53
9.1 Client Behavior ..................................... 53
9.2 Server Behavior ..................................... 55
10 Registrations ....................................... 56
10.1 Overview ............................................ 56
10.2 Constructing the REGISTER Request ................... 57
10.2.1 Adding Bindings ..................................... 59
10.2.1.1 Setting the Expiration Interval of Contact Addresses 60
10.2.1.2 Preferences among Contact Addresses ................. 61
10.2.2 Removing Bindings ................................... 61
10.2.3 Fetching Bindings ................................... 61
10.2.4 Refreshing Bindings ................................. 61
10.2.5 Setting the Internal Clock .......................... 62
10.2.6 Discovering a Registrar ............................. 62
10.2.7 Transmitting a Request .............................. 62
10.2.8 Error Responses ..................................... 63
10.3 Processing REGISTER Requests ........................ 63
11 Querying for Capabilities ........................... 66
11.1 Construction of OPTIONS Request ..................... 67
11.2 Processing of OPTIONS Request ....................... 68
12 Dialogs ............................................. 69
12.1 Creation of a Dialog ................................ 70
12.1.1 UAS behavior ........................................ 70
12.1.2 UAC Behavior ........................................ 71
12.2 Requests within a Dialog ............................ 72
12.2.1 UAC Behavior ........................................ 73
12.2.1.1 Generating the Request .............................. 73
12.2.1.2 Processing the Responses ............................ 75
12.2.2 UAS Behavior ........................................ 76
12.3 Termination of a Dialog ............................. 77
13 Initiating a Session ................................ 77
13.1 Overview ............................................ 77
13.2 UAC Processing ...................................... 78
13.2.1 Creating the Initial INVITE ......................... 78
13.2.2 Processing INVITE Responses ......................... 81
13.2.2.1 1xx Responses ....................................... 81
13.2.2.2 3xx Responses ....................................... 81
13.2.2.3 4xx, 5xx and 6xx Responses .......................... 81
13.2.2.4 2xx Responses ....................................... 82
13.3 UAS Processing ...................................... 83
13.3.1 Processing of the INVITE ............................ 83
13.3.1.1 Progress ............................................ 84
13.3.1.2 The INVITE is Redirected ............................ 84
Rosenberg, et. al. Standards Track [Page 3]