You are here: CSP Developer’s Guide: Common Channel Signaling > 2 Introduction to SS7 > Configuring SS7 Virtual Spans
Purpose
The Virtual Spans software allows configuration of virtual T1, E1, and J1 cards in the CSP. This feature meets all standard software requirements for Excel and does not affect connectivity or performance.
The Virtual Spans feature is common to the Excel SS7, ISDN, DASS2, and DPNSS protocols. By configuring virtual spans on the CSP, physical links or voice circuits with their voice and data traffic can be terminated on another CSP outside the CSP platform. The CSP simply terminates control channels for the SS7 signaling links, ISDN channels, and provides management of SS7 CICS and ISDN B Channels. No difference is apparent to the CSP between virtual and physical spans installed in the chassis.
Before you begin
Virtual cards function in the same way as physical cards in all respects. Insertion and removal of cards will occur logically for the CSP without interruption to service, using the Card Status Query and Card Status Report messages.
The following card types represent the four, eight, and 16-span versions of the E1, T1, and J1 virtual cards:
0xD0 Virtual T1 4 Span
0xD1 Virtual T1 8 Span
0xD2 Virtual T1 16 Span
0xD3 Virtual E1/J1 4 Span
0xD4 Virtual E1/J1 8 Span
0xD5 Virtual E1/J1 16 Span
Typical Operation of Virtual Spans
The following functions apply to typical operation of the Virtual Spans feature:
• A CSP 2090 supports up to 2048 ports and can function with any combination of virtual and physical spans.
• Configuration of virtual spans is done in the same manner as configuration of physical spans.
• Call processing also functions as it would in a CSP system that had only physical spans installed.
• Virtual spans can be configured on local SS7 server nodes or on remote nodes.
• Since virtual slots in the CSP are each assigned a Card Type as if they were installed as physical cards, both matrix controller diagnostics and alarms function normally.
• Messaging occurs normally for SS7, ISDN, DASS2 and DPNSS protocols.
• Product Licensing is supported.
• The same messages that reset a physical card’s tag configuration also reset the equivalent virtual card. You must send the Tag Configuration (0x00D0) message to retag the virtual card. Refer to the Tag Configuration (0x00D0) message in the API Reference for a list of configuration messages that reset the tag configuration of physical cards.
Configuration of Virtual Spans
The Virtual Span configuration sequence incorporates the API messages as shown in the table below:
|
Step |
API Message |
Action |
|---|---|---|
|
1 |
Assign Logical Span ID |
De-assign all of the spans and associated channels in the system. This will remove all virtual slots. These virtual slots must then be configured again. |
|
2 |
Virtual Slot Configure |
Add the virtual slots to the system. |
|
3 |
Assign Logical Span ID |
Assign logical spans to the appropriate slots and offsets. |
|
4 |
Messages from Standard Configuration Sequence (SS7, ISDN...) |
See API Developer’s Guide: Line Cards and Developer’s Guide: Overview. |
|
5 |
Service State Configure |
Bring all spans and associated channels into service. |
|
6 |
Virtual Span Control |
Inform the CSP that the Virtual Spans are operational. (default =non-operational) |
Virtual Card Acts as Physical Card
The Virtual Card Configure message allows the CSP to function as if a "real" physical card has been installed. The host receives the Card Status Report as if the virtual card actually existed. It monitors each card type as real (physical) so that the virtual card, whether it is T1, E1, or J1, can only be inserted or removed through transmission of the Virtual Card Configure message.The Virtual Span Control message supervises the actual spans that the virtual card controls. See the API Reference for a detailed description of these messages.
The virtual card addition and the virtual span status is mirrored on the standby Matrix Controller Series 3 card. Therefore, in the event of the active matrix controller failure the standby will take over, maintaining the virtual card and span status. If there are active calls up at the time of the failure, they will still be maintained on the newly active card.
N+1 Redundancy
N+1 redundancy is not a valid redundancy option for a virtual card.
SS7 and ISDN redundancy mechanisms work exactly the same as they did before, using virtual spans. The only possible implication is that the protocol stacks will query the virtual span state (internal to the system) and will get the latest virtual span status that was configured by the Host using the Virtual Span Control message.
Virtual Spans Example Configuration File
The following is an example configuration file that utilizes the Virtual Card Configure and the Virtual Span Control messages. It sets up two SS7 ANSI stacks and controls CICs on the virtual spans.
The high level CSP configuration is:
Slot 0 SS7 card
Slot 1 Virtual 8-span card
Slot 3 T-ONE 8-span card
Spans 0-3 are assigned and carry the signaling links. Spans 8 to 15 are the spans where the CICs are assigned.
'De-Assign all Logical span ids
00 0d 00 a8 00 00 ff 00 01 11 04 ff ff ff ff
'Virtual card configure (add 8 span T1)
'D0 4 Span T1
'D1 8 Span T1
'D2 16 Span T1
'D3 4 Span E1
'D4 8 Span E1
'D5 16 Span E1
00 0d 00 e0 00 00 FF 00 00 01 01 01 02 01 D1
'Assign logical spans for the links
00 0d 00 a8 00 00 ff 00 01 11 04 00 00 03 00
00 0d 00 a8 00 00 ff 00 01 11 04 00 01 03 01
00 0d 00 a8 00 00 ff 00 01 11 04 00 02 03 02
00 0d 00 a8 00 00 ff 00 01 11 04 00 03 03 03
'Assign spans 8-15 to the virtual slots
00 0d 00 a8 00 00 ff 00 01 11 04 00 08 01 00
00 0d 00 a8 00 00 ff 00 01 11 04 00 09 01 01
00 0d 00 a8 00 00 ff 00 01 11 04 00 0a 01 02
00 0d 00 a8 00 00 ff 00 01 11 04 00 0b 01 03
00 0d 00 a8 00 00 ff 00 01 11 04 00 0c 01 04
00 0d 00 a8 00 00 ff 00 01 11 04 00 0d 01 05
00 0d 00 a8 00 00 ff 00 01 11 04 00 0e 01 06
00 0d 00 a8 00 00 ff 00 01 11 04 00 0f 01 07
'Set span format (ESF, B8ZS, clear channel, 133ft)
00 0d 00 a9 00 00 ff 00 01 0c 02 00 00 52 06
00 0d 00 a9 00 00 ff 00 01 0c 02 00 01 52 06
00 0d 00 a9 00 00 ff 00 01 0c 02 00 02 52 06
00 0d 00 a9 00 00 ff 00 01 0c 02 00 03 52 06
'Set span filter Characteristics (1 second CGA Cleared)
00 0e 00 cd 00 00 ff 00 01 0c 02 00 00 01 00 64
00 0e 00 cd 00 00 ff 00 01 0c 02 00 01 01 00 64
00 0e 00 cd 00 00 ff 00 01 0c 02 00 02 01 00 64
00 0e 00 cd 00 00 ff 00 01 0c 02 00 03 01 00 64
'****************************
'SS7 CONFIGURATION STARTS HERE
'****************************
'-------------------------------------------------------------------------
'Configure First SS7 Stack (A)
'-------------------------------------------------------------------------
'Set Signaling Stack Configure A
'Set our OPC to 00000123 and set the 3 modules to ANSI
00 16 00 5c 00 00 ff 00 01 21 02 00 00 00 00 01 23 03 01 00 02 00 03 00
'Define a Link Set going to 00000987 ID 0
00 0f 00 5d 00 00 ff 00 01 1e 02 00 00 00 00 09 87
'Set the signaling link configuration (SLC 0, Link Id 0, Link set 0)
00 14 00 5e 00 00 ff 00 02 1f 03 00 00 00 0d 03 00 00 00 00 00 00
'Set the Signaling Route Configure for A
'Define a Route to 00 00 09 87 using only Link Set 0
00 14 00 5f 00 00 ff 00 01 20 05 00 00 00 00 00 00 00 09 87 00 00
' Assign DPC-CIC 00000987=0000-060 for A
00 14 00 6a 00 00 ff 00 01 14 07 00 00 00 00 08 00 18 00 00 09 87
00 14 00 6a 00 00 ff 00 01 14 07 00 00 20 00 09 00 18 00 00 09 87
00 14 00 6a 00 00 ff 00 01 14 07 00 00 40 00 0a 00 18 00 00 09 87
00 14 00 6a 00 00 ff 00 01 14 07 00 00 60 00 0b 00 18 00 00 09 87
'-------------------------------------------------------------------------
' Configure Second SS7 Stack (B)
'-------------------------------------------------------------------------
' Set Signaling Stack Configure B
' Set our OPC to 00000987 and set the 3 modules to ANSI
00 16 00 5c 00 00 ff 00 01 21 02 00 01 00 00 09 87 03 01 00 02 00 03 00
' Define a Link Set going to 00000123 ID 1
00 0f 00 5d 00 00 ff 00 01 1e 02 01 01 00 00 01 23
' Set the Signaling Link Configuration (SLC 0, Link Id 1, Link set 0)
00 14 00 5e 00 00 ff 00 02 1f 03 01 01 01 0d 03 00 01 00 00 00 00
' Set the Signaling Route Configure for B
' Define a Route to 00 00 01 23 using only Link Set 1
00 14 00 5f 00 00 ff 00 01 20 05 01 00 01 00 01 00 00 01 23 01 00
' Assign DPC-CIC 00000123=0000-0060 for B
00 14 00 6a 00 00 ff 00 01 14 07 01 00 00 00 0c 00 18 00 00 01 23
00 14 00 6a 00 00 ff 00 01 14 07 01 00 20 00 0d 00 18 00 00 01 23
00 14 00 6a 00 00 ff 00 01 14 07 01 00 40 00 0e 00 18 00 00 01 23
00 14 00 6a 00 00 ff 00 01 14 07 01 00 60 00 0f 00 18 00 00 01 23
'****************************
' SS7 CONFIGURATION ENDS HERE
'****************************
'Bring spans into service
00 0c 00 0a 00 00 ff 00 01 0c 02 00 00 f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 01 f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 02 f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 03 f0
'Bring virtual span into service (optional)
00 0c 00 0a 00 00 ff 00 01 0c 02 00 08 f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 09 f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 0a f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 0b f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 0c f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 0d f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 0e f0
00 0c 00 0a 00 00 ff 00 01 0c 02 00 0f f0
'Bring the Links in Service
00 0d 00 0a 00 00 ff 00 01 09 02 00 00 f0 00
00 0d 00 0a 00 00 ff 00 01 09 02 01 01 f0 00
'Bring channels into service
00 12 00 0a 00 00 ff 01 02 0d 03 00 08 00 0d 03 00 08 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 09 00 0d 03 00 09 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 0a 00 0d 03 00 0a 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 0b 00 0d 03 00 0b 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 0c 00 0d 03 00 0c 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 0d 00 0d 03 00 0d 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 0e 00 0d 03 00 0e 17 f0
00 12 00 0a 00 00 ff 01 02 0d 03 00 0f 00 0d 03 00 0f 17 f0
'Virtual Span Control
'Tell the switch the spans are alive
00 0e 00 e2 00 00 FF 00 01 0C 02 00 08 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 09 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 0a 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 0b 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 0c 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 0d 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 0e 00 01 00
00 0e 00 e2 00 00 FF 00 01 0C 02 00 0f 00 01 00
The Continuity Check is performed for the voice circuits (CICs). This involves testing whether a tone has been properly transmitted at one end and been received at the other on the CIC for which the call is intended. If the Continuity Check passes, then the call continues. If it does not, the call is released.
Since virtual T1, E1, and J1 cards function the same way real cards would in the CSP, the CSP will automatically attempt a Continuity Check for a CIC when an IAM is received. However, since no actual span exists, this Continuity Check will fail. To prevent this, the automatic Continuity Check is disabled in the CSP. In its place Excel uses the "Host-controlled Continuity". Using this feature, the host can initiate a Continuity Check manually by choice only.
This section includes call flow examples for Virtual Spans in both ITU and ANSI.
Incoming Call: IAM Received with COT Required
Outgoing Call: IAM Sent with COT Required
This section includes call flow examples for Virtual Spans in ANSI only.
ANSI CRM Received: NOC=COT Required
ANSI CRM Sent: NOC=COT Required
ANSI IAM Sent: COT Failure: Continuity Recheck
ANSI IAM Received: COT Failure: Continuity Re-check
