ISUP Flow Panel

In VoLTE/IMS Nodal testing, the ISUP/SIP tab on the Nc > Control tab allows you to define the transport used to establish, modify, and terminate ISUP/SIP (Session Initiation Protocol) control protocol and modify content of the outgoing SIP messages. You may define a ISUP/SIP message content using default templates or configure a custom ISUP/SIP message format and/or a custom PSTN/SDP message format.

In MME Nodal and IMS Node, the ISUP Flow tab becomes available when Nc-ISUP is enabled. More detail in ISUP-based call handling is specified in the 3GPP TS 23.292.

IMS Nodal NC Interface:

ISUP/SIP Flow Mode:

You cannot modify a flow as SIP is defined by a combination of the following enablers/controls on VoLTE tab:

IMS Nodal NC Interface:

Transport

Enable TLS

ISUP/SIP Flows and Messages:

(Enable Supplementary not supported)

ISUP/SIP Messages

ISUP/SIP Call Flow (Left pane)
ISUP/SIP Message Editor (Right pane)

ISUP/SIP Call Flow Templates for IMS Nodal NC Interface:

PSTN_ORIG_Normal_Call
PSTN_ORIG_Make_then_Cancel_Call
PSTN_TERM_Normal_Answer
PSTN_TERM_Auto_Answer
PSTN_TERM_Reject_Call
PSTN_TERM_Ignore_Call_Silence
PSTN_TERM_Ignore_Call_with_ACM
PSTN_TERM_Send_Reliable_Provisional_Response
PSTN_TERM_Send_UnReliable_Provisional_Response
PSTN_Registration
PSTN_Local_Disconnect
PSTN_Remote_Disconnect

Transport

Select the type transport protocol used to establish, modify, and terminate ISUP/SIP IMS sessions.

Tcl Parameter: NcSipTransport

Enable TLS

Select to Enable TLS - Only supported when transport type is TCP. A new Tab TLS will be enabled where Cipher Suites, Private Key, and certificate can be used during TLS handshake.

Available on MME Nodal, SGW Nodal, IMS Nodal, IMS Node and IP application test cases.

Tcl Parameter: NcSipTlsEn

MME Nodal / IMS Node Nc-ISUP Interface:

Nc ISUP Timers

T1 Release Retransmit Timer (s)
T5 Awaiting Release Complete Timer (m)
T7 Awaiting Address Complete Timer (s)

Nc ISUP Timers

T9 Awaiting AnswerTimer (s)
T16 Reset Circuit Retransmit Timer (s)
T17 Maintenance Intervention Timer (m)

ISUP/SIP Flows and Messages:

(Enable Supplementary not

Complete ISUP Message Flow

ISUP/SIP Messages

ISUP/SIP Call Flow (Left pane)
ISUP/SIP Message Editor (Right pane)

ISUP/SIP Call Flow Templates for Nc-ISUP:

Complete ISUP Message Flow

ISUP Messages:

Initial Address Message
Address Complete Message
Call Progress Message
Answer Message
Release Message
Release Complete Message
Reset Circuit Message

Nc-ISUP Timers

2.3.3.7. ISUP call state transition

T1 Release Retransmit Timer (s)	Enter the T1 Release Retransmit timer in seconds. See ISUP Call state transition with timer details listed in the flow above. Range : 15 to 60 Default 60 Tcl Parameter: NcT1Time
T5 Awaiting Release Complete Timer (m)	Enter the T5 Awaiting Release Complete timer in milliseconds. See ISUP Call state transition with timer details listed in the flow above. Range : 5 to 15 Default 5 Tcl Parameter: NcT5Time
T7 Awaiting Address Complete Timer (s)	Enter the T7 Awaiting Address Complete timer in seconds. See ISUP Call state transition with timer details listed in the flow above. Range : 20 to 30 Default 20 Tcl Parameter: NcT7Time
T9 Awaiting Answer Timer (s)	Enter the T9 Awaiting Answer timer in seconds. See ISUP Call state transition with timer details listed in the flow above. Range : 90 to 180 Default 90 Tcl Parameter: NcT9Time
T16 Reset Circuit Retransmit Timer (s)	Enter the T16 Reset Circuit Retransmit timer in seconds. See ISUP Call state transition with timer details listed in the flow above. Range : 16 to 60 Default 20 Tcl Parameter: NcT16Time
T17 Maintenance Intervention Timer (m)	Enter the T17 Maintenance Intervention timer in milliseconds. See ISUP Call state transition with timer details listed in the flow above. Range : 5 to 15 Default 5 Tcl Parameter: NcT17Time

ISUP/SIP Messages - IMS Nodal NC

The ISUP/SIP tab | pane displays two columns/panes. The left pane displays ISUP/SIP message flows line diagram and the right column/pane displays the relevant message header and message body content of ISUP/SIP messages. The left pane is further divided into two sections - ISUP Messages (Party A) to the left of MGC and SIP messages (Party B) to the right of MGC. In the example below, ISUP Message - Initial Address Message is highlighted. When you click on a message (of a flow) in the left pane, the message is highlighted and on the right column/pane, displays the ISUP/SIP message headers and SDP (ISUP/SIP message body, where applicable) for the highlighted message.

In this example, ISUP Message - Initial Address Message is highlighted. The right column/pane, displays the ISUP message headers and body that make up the "Initial Address Message".

In this example, SIP Message - 1xx on INVITE is highlighted. The right column/pane, displays the SIP message headers and SDP (SIP message body) that make up the "1xx on INVITE":

NOTES:

Landslide encapsulates configured ISUP messages as parts of SIP Message body.
ISUP/SIP Message Template applies to SIP Subscriber and SIP Endpoint objects, but does not apply to Proxy/Registrar.

A default configuration is displayed as template and allows you to modify ISUP/SIP headers and body (PSTN/SDP), where applicable. (A template displays for every ISUP/SIP message available to be modified). The combination of the configurable ISUP/SIP message format and the configurable PSTN/SDP message format allows you to customize ISUP/SIP messages to your SIP implementation (e.g., interoperability testing).

Open a ISUP/SIP Flow Template

Click to open the ISUP/SIP Flow Template window and select a ISUP/SIP Flow from available libraries.

NOTE: The Save Template Dialog automatically use the last opened/saved template name and you may edit as required.

Save as Data Profile Template

Click to save elected ISUP/SIP Flow as a template.

NOTE: Copy of Data Profile and ISUP/SIP Flow Templates prevent copy/move of system owned dependent items, e.g. {Basic}, {Scenario…} library items.

Pop-up ISUP/SIP Flow

Click to to open the ISUP/SIP Flow in a larger re-sizable window.

SIP Flow Line Diagram

Click on any ISUP/SIP Flow MessageISUP/SIP Flow Message (left column) to enable ISUP/SIP Message editor (right column)

NOTE: If a ISUP/SIP message is not available for editing the right column remains blank. (Headers and SDP tab remain blank).

ISUP/SIP Messages - MME Nodal / IMS Node NC-ISUP

Below is a sample flow of ISUP-based call initiation: Reference : TS 23.292 V 14.2.0 Section 7.3

The ISUP/SIP tab | pane displays two columns/panes. The left pane displays ISUP/SIP message flows line diagram and the right column/pane displays the relevant message header and message body content of ISUP/SIP messages. The left pane is further divided into two sections - ISUP Messages (Party A) and (Party B). In the example below, ISUP Message - Initial Address Message is highlighted. When you click on a message (of a flow) in the left pane, the message is highlighted and on the right column/pane, displays the ISUP/SIP message headers and SDP (ISUP/SIP message body, where applicable) for the highlighted message.

In this example, ISUP Message - Initial Address Message on MME Nodal is highlighted. The right column/pane, displays the ISUP message headers and body that make up the "Initial Address Message".

In this example, ISUP Message - Initial Address Message on IMS Node is highlighted:

Open a ISUP/SIP Flow Template

Click to open the ISUP/SIP Flow Template window and select a ISUP/SIP Flow from available libraries.

NOTE: The Save Template Dialog automatically use the last opened/saved template name and you may edit as required.

Save as Data Profile Template

Click to save elected ISUP/SIP Flow as a template.

NOTE: Copy of Data Profile and ISUP/SIP Flow Templates prevent copy/move of system owned dependent items, e.g. {Basic}, {Scenario…} library items.

Pop-up ISUP/SIP Flow

Click to to open the ISUP/SIP Flow in a larger re-sizable window.

SIP Flow Line Diagram

Click on any ISUP/SIP Flow MessageISUP/SIP Flow Message (left column) to enable ISUP/SIP Message editor (right column)

NOTE: If a ISUP/SIP message is not available for editing the right column remains blank. (Headers and SDP tab remain blank).

ISUP/SIP Call Flow (Left Pane)

The ISUP/SIP Call Flow (Left Pane) shows a flow of messages expected for a current test configuration. When you select a message in the flow control area, a default ISUP/SIP templates is shown in the editing windows (Right Pane).

The line diagram illustrates standard representation of the selected message. Each message (represented by a horizontal line) includes a text string (Field) or a combination of a text string and predefined parameter type (Filler; shown in blue on the right pane) for SIP Messages. ISUP Messages include Parameter, Integer/Hex Value and Hex Value.

NOTES:

As of Release 15.0, a new design, uses a single Super-Flow with a fixed set of all possible messages.
The GUI will filter the display to only show the messages that apply to the configuration. The Super-Flow, Flow ID is 999.
All previously saved tests containing Flows with IDs 1-34 will be automatically upgraded to the new Super-Flow. When a Template is opened, able to select from all Flow IDs and be automatically upgraded into the Super-Flow.
The Super-Flow has a display more aligned with how SIP Scripts display, but instead of "Actions" there are "Categories" such as "Registration", "Call", "Provisional Response", etc. As you enabled/disable features, the categories will be shown or hidden, and some messages inside categories are shown or hidden.
Unlike the old flows, all messages (shown and hidden) are always saved with the flow, and in Tcl API, the user has access to all the messages at all times. In the Tcl API, there is an "enabled" flag set upon validation of the test to indicate which messages actually matter. Only the messages that shown (GUI) / enabled (Tcl) are actually used by the TS.
Tcl API Scripts should be replaced with new Super-Flow as soon as possible by the customers.
Save-As-Tcl from the GUI will show how the new Super-Flow looks and/or ls::perform Validate on Tcl script to upgrade old Flow to Super-Flow.

Use Default

Selected by default. When selected, default content of ISUP/SIP headers and ISUP/SIP body are used in the test case.

When not selected, the template will be used to replace the default message content.

SIP Flow Line Diagram

Click on any ISUP/SIP Flow Message (left column) to enable ISUP/SIP Message editor (right column)

NOTE: If a ISUP/SIP message is not available for editing the right column remains blank. (SIP Headers and SDP tab remain blank). ISUP Parameters, Integer/Hex Value and Hex Value remain blank.

ISUP/SIP Messages Editor (Right Pane)

Use Default

When selected, for all messages in the test case, Use Default is disabled for individual message (on the Right Pane).

When not selected, individual message editor will be enabled for configuration for SIP Messages/ISUP Messages.

SIP Messages

Reset, Field+ (list), and Filler+ (list)

Available when Use Default is not selected. The Reset, Field+ , and Filler+Reset, Field+ , and Filler+ buttons help you with the editing process. You may replace the original Fields and Fillers in the message Header/SDP by any text.

Reset	Click to reset the modified content back to the default configuration
Field+	Click to display a list of text string. Select a text string to insert within your SIP message. You may also right-click at the insertion point, select the Insert SIP Field option from the context menu.
Filler+	Click to display a list of parameters/variables. Select a parameter to insert within your SIP message, which is shown in blue. You may also right-click at the insertion point and select the Insert Auto-Fill option from the context menu. See SIP Fillers for details. See SDP Fillers for details.
CRLF/CR/LF	Click to insert carriage return (CR) or line feed (LF) characters or both (CRLF) at the selected byte/offset or right-click at the insertion point and select the New Line Mode option from the context menu.
Right-Click context menu	You may also right-click at the insertion point and select the required option from the context menu: Insert SIP Field, Insert Auto-Fill, or New Line Mode (CRLF, CR, LF). You may also Open a QuickList and Add the Filler/Field to the QuickList for later use.

Editing SIP Message

Clear Use Default selected (both in the Left and the Right panes).
Select the required flow (represented by a line in the left pane), a pre configured template displays (where applicable) on the right pane.
Click the Header/SDP tab to edit, insert, modify, delete information by using the Field + (list) or the Filler + (list) as required.

Example of what happens when editing

Text string (field) that is not followed by a parameter (filler):

a=sendonly{CR}{LF}

Text string a=sendonly will always be included in the final message.

• Text string followed by a variable/parameter/filler:

Contact: <{Contact1-uri}>{CR}{LF}
If {Contact1-uri} exists in the original message then the final message will include string.

Contact: <sip:[email protected];transport=udp>

If {Contact1-uri} does not exist in the original message then the whole string will not be in the final message.

Contact: <sip:[email protected];transport=udp>

Conditional Parameters (used when parameters used in your template does not exist in the original message)

Since a configurable SIP message is generated from an existing message, some parameters used in your template may not exist in the original message. You may use “…-if” parameter to take care of such cases.

-if	Parameters with -if at the end are applied to the text string that starts from the previous parameter (Filler). Parameter with –if be inserted to indicate that this text string should be skipped if it does not exist in the message.
Examples:	a=sendonly{M2-a-sendonly-if}{CR}{LF} Text string a=sendonly will be included in the final message only if it exists in the original message.
	a=sendonly{CR}{LF} Attribute a=sendonly will be always included into the final message regardless of whether it exists in the original message.
	“Contact: <{Contact1-uri}>{Contact1-uri-if};isfocus{Contact1-isfocus-if}{CR}{LF}” {Contact1-uri-if} is used to include the right angle bracket > if the text string isfocus does not exist in the original message.

NOTE: For example, in the following string: Contact: <{Contact1-uri}>;isfocus{Contact1-isfocus-if}{CR}{LF}, if isfocus does not exist in the original message, the whole string >;isfocus will be missed/skipped and not included in the message.

Example SIP Header and Template

Example SDP

Editing ISUP Message

Clear Use Default selected
Select the required flow (represented by a line in the left pane), a pre configured template displays (where applicable) on the right pane.
Double Click the Integer/Hex Value - Select new item from down menu. If item has been changed, the value in the Hex Value will be changed (from a default of zero). See examples for IMS Nodal Nc:

Change Value of End-To-end information from default (no end-to-end information) to end-to-end information. See Hex value change from 0 to 1.

Examples for Nc-ISUP:

Click the Add button to add an optional parameter: Table of Optional Parameters will pop up:

ISUP Message Types

References Nc-ISUP

3GPP TS 23.216: "Single Radio Voice Call Continuity (SRVCC); Stage 2"
3GPP TS 29.163: "Interworking between the IP Multimedia (IM) Core Network (CN) subsystem and Circuit Switched (CS) networks"
3GPP TS 23.292: "IP Multimedia Subsystem (IMS) centralized services; Stage 2"
ITU Q.761-Q.764 ISDN User Part (ISUP) Protocol suite
IETF RFC 4666: SS7 MTP3 User Adaption Layer (M3UA).
3GPP TS 23.232: "SIP-I based circuit-switched core network; Stage 2"
3GPP TS 23.205: "Bearer-independent circuit-switched core network; Stage 2"

References

[1] RFC 3372 Session Initiation Protocol for Telephones (SIP-T): Context and Architectures

[2] RFC 3261 SIP: Session Initiation Protocol

[3] RFC 3204 MIME media types for ISUP and QSIG Objects

[4] RFC 3398 Integrated Services Digital Network (ISDN) User Part (ISUP) to Session Initiation Protocol (SIP) Mapping

[5] RFC 2976 The SIP INFO Method

[6] RFC 2833 RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals

[7] ITU Q.1912.5 Interworking between Session Initiation Protocol (SIP) and Bearer Independent Call Control protocol or ISDN User Part

[8] RFC 4904 Representing Trunk Groups in tel/sip Uniform Resource Identifiers (URIs)

[9] RFC 3841 Caller Preferences for the Session Initiation Protocol (SIP)

[10] RFC 3578 Mapping of Integrated Services Digital Network (ISDN) User Part (ISUP) Overlap Signalling to the Session Initiation Protocol (SIP)

[11] RFC 3264 An Offer/Answer Model with the Session Description Protocol (SDP)

[12] RFC 3204 MIME media types for ISUP and QSIG Objects

[13] RFC 3398 Integrated Services Digital Network (ISDN) User Part (ISUP) to Session Initiation Protocol (SIP) Mapping

[14] RFC 2976 The SIP INFO Method

[15] RFC 2046 Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types

[16] RFC 3966 The tel URI for Telephone Numbers

[17] 3GPP TS 24.229 Signaling flows for the IP multimedia call control based on Session Initiation Protocol (SIP) and SDP; Stage 3

[18] 3GPP TS 23.228 IP Multimedia Subsystem (IMS); Stage 2

[19] 3GPP TS 29.333 Multimedia Resource Function Controller (MRFC) - Multimedia Resource Function Processor (MRFP) Mp Interface; Stage 3

[20] 3GPP TS 23.231 SIP-I based circuit-switched core network; Stage 2

[21] 3GPP TS 23.205 Bearer-independent circuit-switched core network; Stage 2

[22] 3GPP TS 29.231 Application of SIP-I Protocols to Circuit Switched (CS) core network architecture; Stage 3

[23] ITU-T Q.1912.5 Interworking between Session Initiation Protocol (SIP) and Bearer Independent Call Control Protocol or ISDN User Part

[24] ITU-T Q.761 ISDN User Part Functional Description

[25] ITU-T Q.762 ISDN User Part General Functions of messages and signals

[26] ITU-T Q.763 ISDN User Part

[27] ITU-T E.164 E.164 : The international public telecommunication numbering plan

[28] RFC 4715 The Integrated Services Digital Network (ISDN) Subaddress Encoding Type for tel URI

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