AITIA	GyX_SCTP - The SS7-over-IP (SigTran) interface module	GyX_SCTP

The SS7-over-IP (SigTran) interface module
`("GyX_SCTP")`

Features
Basic operation
User interface
Logging
Configuration
SNMP alarm list
Version history

Features

Provides signaling interface for a main functional module
Connects to the signaling network using SCTP/IP connection
Acts as an active element of the SS7 network
Receives queries with input parameters via TCP/IP from the main module
Transfers queries to the SS7 network
Optionally writes M3UA (SS7) messages into binary message files
Sends received answers with output parameters to the main module
Can act as SCTP "client" or "server", as well

Basic operation

Uses Ethernet interface(s) for connecting to the IP based signaling network
Maintains SCTP functions on two associations
Provides MultiHoming feature
Logs queries and responses
Creates SNMP traps

User interface

The main menu

Menu	Menuitem	Shortcut(s)	Meaning
[Log]
	Find line containing...	(Ctrl-F)	Finds text in log window
	Find next matching line	(F3)	Finds next occurrence of text in log window
	Details		Detail level of logging (Off, Normal, Detailed, or Debug)
[SCTP]
	A: Allow auto-connecting	(left-side )	Allows automatic (re-)connecting to the SCTP server on association A
	A: Shutdown now!		Immediately disconnects association A
	B: Allow auto-connecting	(right-side )	Allows automatic (re-)connecting to the SCTP server on association B
	B: Shutdown now!		Immediately disconnects association B
[TCP Connection]
	Disconnect		Shutting down of all active connections
	Zero counters		Request and answer counters of TCP connection will be cleared on the status bar
[Options]
	Auto scroll	()	Allows automatic scrolling of the log screen
	Save settings		Saves actual settings into the configuration (`INI`) file
[Debug]	Items in this menu are only for debug and test purposes!
	A: Send an ASPsm/ASPUP message		Sends an "ASP state maintenance/ASP up" message on association A
	A: Send an ASPsm/ASPDN message		Sends an "ASP state maintenance/ASP down" message on association A
	A: Send an ASPtm/ASPAC message		Sends an "ASP traffic maintenance/ASP active" message on association A
	A: Send an ASPtm/ASPIA message		Sends an "ASP traffic maintenance/ASP inactive" message on association A
	A: Send an SS7snm/DAUD(remotePC) messages		Sends an "SS7 signaling network maintenance/Destination state audit" message using `INI/[SS7]/wTxRLDPCIfRemotelyNotSetA` as the "Affected point code"
	B: Send an ASPsm/ASPUP message		Sends an "ASP state maintenance/ASP up" message on association B
	B: Send an ASPsm/ASPDN message		Sends an "ASP state maintenance/ASP down" message on association B
	B: Send an ASPtm/ASPAC message		Sends an "ASP traffic maintenance/ASP active" message on association B
	B: Send an ASPtm/ASPIA message		Sends an "ASP traffic maintenance/ASP inactive" message on association B
	B: Send an SS7snm/DAUD(remotePC) messages		Sends an "SS7 signaling network maintenance/Destination state audit" message using `INI/[SS7]/wTxRLDPCIfRemotelyNotSetB` as the "Affected point code"
	Send a T/DATA/SS7/SST(remotePC,1) message		Sends an "SS7/Subsystem status test" message with SubSystemNumber=1 using `INI/[SS7]/wTxRLDPCIfRemotelyNotSetA` as the "Affected point code"
	Send a T/DATA/SS7/SST(remotePC,HLR=6) message		Sends an "SS7/Subsystem status test" message with SubSystemNumber=6 using `INI/[SS7]/wTxRLDPCIfRemotelyNotSetA` as the "Affected point code"
	Send a T/DATA/SS7/SST(remotePC,VLR=7) message		Sends an "SS7/Subsystem status test" message with SubSystemNumber=7 using `INI/[SS7]/wTxRLDPCIfRemotelyNotSetA` as the "Affected point code"
	Send a T/DATA/SS7/SST(remotePC,MSC=8) message		Sends an "SS7/Subsystem status test" message with SubSystemNumber=8 using `INI/[SS7]/wTxRLDPCIfRemotelyNotSetA` as the "Affected point code"

Status-line of associations

SCTP: Status of the association. It becomes grey after the successful SCTP/INIT.
- Idle (red) → There is no SCTP association established
- Connecting.../Disconnecting... (yellow) → Connecting/disconnecting state, tries to connect or disconnect to or from the server
- Connected → SCTP association is established
ASP: Status of the Application Server Process
- red → There is no M3UA connection, ASP state is "ASP-down" (initial state or ASPsm/ASPDN message received)
- yellow → ASP state is "ASP-inactive"; ASPsm/ASPUP (or ASPtm/ASPIA) message arrived
- grey → ASP state is "ASP-active"; ASPtm/ASPAC message arrived
bps: Message bits received in the last second
Rx/Tx: The number of messages received and sent on the SCTP interface
Error counters:
- sctp: Number of SCTP disconnections
- asp: Number of M3UA disconnections
- dsp: Number of communication errors between the interface card and the program
- msu: Received an uninterpretable or misaddressed MSU (for example with wrong Point Code)
MSU's buffered for Tx: The number of MSU's buffered for transmitting
TCP connection: State of the TCP connection. It becomes gray after the main module connected
Rx/Tx: The number of messages received and sent on the TCP interface
RxBuffered: Number of messages in the receive buffer
RxOverrun: Number of those messages which arrived when the TCP buffer is full
TxCongested: Number of messages which are dropped due to congestion

The bottom status-line

Uptime: Time elapsed since module has been started up;
- hovering over: Start date and time
- left-click: Kernel and user time

Logging

The module creates daily logfiles about its working. The name of the logfile is "Modulename_YYYYMMDD.log" reflecting the day when it is created.
The module can write information into the logfile and onto the screen with several detail levels set by the [Log]/Details menu item. The logging level can be:

Off (0) - warnings/errors are only reported (minimal logfile size and CPU usage)
Normal (1) - information about normal operation are also written into the logfile/screen
Detailed (2) - every received and sent signaling messages are logged
Debug (3) - hexadecimal information of messages is recorded (largest logfile and CPU usage)

Status line counters are logged in every fifteen minutes irrespectively of logging level actually set.

The different colors of log entries have different meanings:

Code Color Usage
0 Black Compact data record
1 Red Errors
2 Green Open/close output file/stream
3 Blue Open/close input file/stream
4 Yellow Warnings
5 Light Gray Detailed data (debug info)
6 Dark Grey Detailed data (user info)
7 Purple Operator intervention;
Errors with emphasis

Code	Color	Usage
0	Black	Compact data record
1	Red	Errors
2	Green	Open/close output file/stream
3	Blue	Open/close input file/stream
4	Yellow	Warnings
5	Light Gray	Detailed data (debug info)
6	Dark Grey	Detailed data (user info)
7	Purple	Operator intervention; Errors with emphasis

Configuration (INI) file settings

Section	Entry	Example	Meaning
[Position]
	iLeft	140	Position of the program module on the display screen
	iTop	72	Position of the program module on the display screen
	iWidth	995	Position of the program module on the display screen
	iHeight	694	Position of the program module on the display screen
[Options]
	bAutoScroll	True	(Refer to the `[Options]/Auto scroll` menu item!)
[SCTP]
	wAutoConnectIntervalSec	2	Period for automatic connection of SCTP associations
	bAllowAutoConnectAtStartup_A	True	(Refer to the `[SCTP]/A: Allow auto-connecting` menu item!)
	bAllowAutoConnectAtStartup_B	True	(Refer to the `[SCTP]/B: Allow auto-connecting` menu item!)
	sLocalIPAddress#N	10.0.123.10	Local IP addresses for SCTP connections. If more IP addresses are listed then multiple paths are used in associations (MultiHoming). N runs from 0 to 9.
	sRemoteIPAddress_A#1, sRemoteIPAddress_A#2	10.0.123.20, 10.0.123.21	Alternative IP addresses of the SCTP server A.
	sRemoteIPAddress_B#1, sRemoteIPAddress_B#2	10.0.124.20, 10.0.124.21	Alternative IP addresses of the SCTP server B.
	wRemoteSCTPPort_A	2905	SCTP port of the SCTP server A
	wRemoteSCTPPort_B	2905	SCTP port of the SCTP server B
	wLocalSCTPPort	2905	Optional parameter if the SCTP server sticks to a given port. Normally, it should not be used.
	byClientServerMode	0	0 = ClientOnly (actively tries to connect to the remote SCTP peer) 1 = ServerOnly (receives connection attempts from an SCTP peers) 2 = Bisex (combined mode)
	wHeartbeatIntervalSec	10	SCTP/HEARTBEAT period
	dwMaxRTOmsec	15000	Retransmission Timeout value in milliseconds
	dwMaxRetransmitsPerInit	3	Maximum number of retransmission for INIT chunks
	dwMaxRetransmitsPerAssociation	9	Maximum number of retransmissions per association
	dwMaxRetransmitsPerPath	4	Maximum number of retransmissions per path
	dwDelayedACKmsec	50	Defines the delay in millisec used during delayed acknowledgement algorithm
	byIPfieldDSCP	16	Default value of DSCP field of IP protocol level can be overwriten by this value. Please note: this feature should also be enabled in Windows operating system by modifying the related registry entry!
[SS7]
	wTxRLDPCIfRemotelyNotSetA	201	The point code of the remote SS7 device on association A if it is not set by the main module
	wTxRLDPCIfRemotelyNotSetB	201	The point code of the remote SS7 device on association B if it is not set by the main module
	wTxRLOPCIfRemotelyNotSetA	13	Local point code used on association A if it is not set by the main module
	wTxRLOPCIfRemotelyNotSetB	200	Local point code used on association B if it is not set by the main module
	bNoAlternateRouteForNeighbours	False	If it is True and `wTxRLDPCIfRemotelyNotSet` entries are set the module tries to select an SCTP association for outgoing signalling messages based on the destination point code. It must not be 'True' when `wTxRLDPCIfRemotelyNotSet` entries have the same value.
	bApplyRouteSeparationBasedOnSLS	True	In case of 'True' the outgoing association is selected based on the SLS of the MSUs applying the following rule: If the least significant bit of SLS is 0 then the message is sent on association 'A' If the least significant bit of SLS is 1 then the message is sent on association 'B' It must not be 'True' when `bNoAlternateRouteForNeighbours` is 'True'.
[SCCP routing preferences]	This simple routing table helps minimize the cross-MSS traffic. First match is used, and MSUs with GTs that do not have their prefixes listed here remain untouched. Note that UDTS and XUDTS and LUDTS messages are unaffected
	bForced	False	If False, then DPC of UDT and XUDT and LUDT messages is set only if it is not previously set by the sending application. If True, then DPC of UDT and XUDT and LUDT messages is set anyway.
	+36909990001	901	DPC of messages having SCCP.CapPA.GT=36909990001 (e.g.: GT of MSS #1) is set to '901' (e.g.: DPC of MSS #1), after that messages are sent towards MSSs based on the rules set in INI/[SS7] section
	+36909990002	902	DPC of messages having SCCP.CapPA.GT=36909990002 (e.g.: GT of MSS #2) is set to '902' (e.g.: DPC of MSS #2), after that messages are sent towards MSSs based on the rules set in INI/[SS7] section
	+36909990003	901	DPC of messages having SCCP.CapPA.GT=36909990003 (e.g.: GT of MSS #3) is set to '901' (e.g.: DPC of MSS #1; i.e.: MSS #3 is reached preferably via MSS #1), after that messages are sent towards MSSs based on the rules set in INI/[SS7] section
	+3690	902	All other MSSs (with the GT prefix of '3690') are reached preferably via MSS #2
	+3620	901	Prefer MSS #1 for PGSM (with the GT prefix of '3620')
	+3630	902	Prefer MSS #2 for W900 (with the GT prefix of '3630')
	+3650	901	Prefer MSS #1 for Digi (with the GT prefix of '3650')
	+3670	902	Prefer MSS #2 for Voda (with the GT prefix of '3670')
[RemoteRequest]
	wLocalTCPPort	3000	Port number, where the remote modules can connect
	bSuppressDisconnectTrap	True	When it is true traps on disconnecting TCP connection are suppressed
	sRemoteIPAddress	127.0.0.1	The main module with this IP address can connect to the GyX module Used for station restriction, leave it empty for no restriction.
	bForwardUpDownSignal	False	If it is 'True' in case of SCTP disconnection/connection a Down/Up signal is emitted toward the main module. In case of Up/Down signal reception SCTP associations are enabled to connect/shut down.
[SGAfiles]			Entries in this section are reloaded once per every second. sSigLinkID entry may consist of two characters. sFileNamePrefix entry (as well as the contents of sFilesPath entry) is considered when opening an SGA file. Leave (or change) sFilesPath entry empty not to write SS7 data into file.
	sFilesPath	D:\SS7Files	Path for SGA files
	sFileNamePrefix	GyX_SCTP	File name prefix to distinguish between SS7 files created by different GyX_SCTP modules concurrently.
	sSigLinkID	HR	Two character long link ID to identify the messages.
	dwFilePeriodMin	15	Period of SGA files creation.
[Advanced]
	wLogDetailLevel	3	(Equals to the listed order; refer to the `[Log]/Details` menu item!)
	dwMaxLinesInLogWindow	1000	Number of lines in the log window on screen
	sLogFilesPath	d:\LogFiles	Path for the LOG files
	sTrapFilesPath	d:\TrapFiles	Path for the SNMP Trap files to be sent
	bAlternateTrapUID	False	Allows using fixed UIDs in SNMP traps (See SNMP trap list below for details)
	wThreadPeriod	100	Time period when idle threads are given CPU time slice (given in milliseconds)
	sID	001	This 9 character identifier is indicated in the caption of the module and placed in the alarm generated by the module.

SNMP trap list

UID	Type	Text	Remarks	To Do
If `bAlternateTrapUID` is set to TRUE
9	CEA	`'GyX/SCTP v1.19' module is started.`	Send a welcome message; indication of module start-up
9	CRI	`'GyX/SCTP v1.19' module has been shut down by operator.`	Send a farewell warning message; indication of module shut-down	Start the `'GyX/SCTP v1.19'` module
90	CEA	`SCTP(A) ASP Traffic is up.`
90	CRI	`SCTP(A) ASP Traffic has died. (shutdown)`	Connection is down; The other side has sent an SCTP/SHUTDOWN message.	Check if the SCTP server is working and the connection parameters are set properly.
90	CRI	`SCTP(A) ASP Traffic has died. (lost)`	The SCTP server has become unreachable (there is no ACK for SCTP/HEARTBEAT).	Check if the SCTP server is alive and the IP connection is working properly.
90	CRI	`SCTP(A) ASP Traffic has died. (operator)`	Connection is down. Operator has executed the `[SCTP]/Shutdown now!` menu item.	Set `SCTP(A)` auto-connecting to be true (`[SCTP]/A: Allow auto-connecting` menu item)
91	CEA	`SCTP(B) ASP Traffic is up.`
91	CRI	`SCTP(B) ASP Traffic has died. (shutdown)`	Connection is down; The other side has sent an SCTP/SHUTDOWN message.	Check if the SCTP server is working and the connection parameters are set properly.
91	CRI	`SCTP(B) ASP Traffic has died. (lost)`	The SCTP server has become unreachable (there is no ACK for SCTP/HEARTBEAT).	Check if the SCTP server is alive and the IP connection is working properly.
91	CRI	`SCTP(B) ASP Traffic has died. (operator)`	Connection is down. Operator has executed the `[SCTP]/Shutdown now!` menu item.	Set `SCTP(B)` auto-connecting to be true (`[SCTP]/B: Allow auto-connecting` menu item)
92	INF	`TCP connection: Up.`	First incoming TCP connection. Only if `[RemoteRequest]/bSuppressDisconnectTrap=False`.
92	ERR	`TCP connection: Closed by operator.`	Operator shut TCP connection down by the `[TCP connection]/Disconnect` menu item. Only if `[RemoteRequest]/bSuppressDisconnectTrap=False`.	Connection will automatically be re-established by the main module.
92	CEA	`TCP connection: Closed (i.e., up again).`	Main module has established connection after a disconnection. Only if `[RemoteRequest]/bSuppressDisconnectTrap=False`.
92	ERR	`TCP connection: Closed by the remote side.`	The main module is shut down or the network connection broke down.	Start the main module or check the network connection between `GyX_SCTP` and the main module.
93	ERR	`TCP connection: Failed to send MSU! (cause).`	Incoming MSUs can not be forwarded to the functional module due to the problem indicated in brackets.	Check the connection to the functional module or the operation of it.
93	CEA	`TCP connection: Failed to send MSU! (i.e., OK again).`	MSUs again can be forwarded to the functional module.
94	WAR	`Received an unexpected MSU, or its format is unknown.`	Badly formatted MSU or the of the arrived MSU is not recognized	Check if the MSU traffic directed to this device is addressed and formatted properly
If `bAlternateTrapUID` is set to FALSE
N	CEA	`'GyX/SCTP v1.19' module is started.`	Send a welcome message; indication of module start-up
++N	CRI	`'GyX/SCTP v1.19' module has been shut down by operator.`	Send a farewell warning message; indication of module shut-down	Start the 'GyX/SCTP v1.19' module
0	INF	`SCTP(A/B) ASP Traffic is up.`	Connection A/B is up for the very first time; subsequent ones are indicated with the corresponding CEA
++N	CRI	`SCTP(A/B) ASP Traffic has died. (shutdown)`	Connection is down; The other side has sent an SCTP/SHUTDOWN message.	Check if the SCTP server is working and the connection parameters are set properly.
++N	CRI	`SCTP(A/B) ASP Traffic has died. (lost)`	The SCTP server has become unreachable (there is no ACK for SCTP/HEARTBEAT).	Check if the SCTP server is alive and the IP connection is working properly.
++N	CRI	`SCTP(A/B) ASP Traffic has died. (operator)`	Connection A/B is down because the operator has executed the `[SCTP]/Shutdown now!` menu item.	Try to set auto-connecting to be true to enable the connection (`[SCTP]/(A\|B): Allow auto-connecting` menuitem)
N	CEA	`SCTP(A/B) ASP Traffic has died.`	When connection A/B is up after a down. Ceasing for the corresponding "SCTP(A/B) ASP Traffic has died." alarms.
0	INF	`TCP connection: Up.`	Given TCP connection is up for the very first time; subsequent ones are indicated with the corresponding CEA
++N	ERR	`TCP connection: Closed by the remote side.`	Given TCP connection is down; other side closed the connection
++N	ERR	`TCP connection: Closed by operator.`	Given TCP connection is down; operator closed the connection
N	CEA	`TCP connection: Closed (i.e., up again).`	TCP connection is up after a down
++N	ERR	`TCP connection: Failed to send MSU! (cause).`	Incoming MSUs can not be forwarded to the functional module due to the problem indicated in brackets.	Check the connection to the functional module or the operation of it.
N	CEA	`TCP connection: Failed to send MSU! (i.e., OK again).`	MSUs again can be forwarded to the functional module.
++N	ERR	`TCP connection: Received %u bytes of illegible request - dropping connection.`	Illegal request has been received	Check if the remote module works properly or the TCP connection is reliable. Possibly not an appropriate version of main module is used or an illegal connection was made up.
++N	ERR	`TCP connection: Received and calculated CRC do not match - dropping connection.`	Illegal request has been received	Check if the remote module works properly or the TCP connection is reliable. Possibly not an appropriate version of main module is used or an illegal connection was made up.
++N	ERR	`TCP connection: Received request with bad MagicCode - dropping connection.`	Illegal request has been received	Check if the remote module works properly or the TCP connection is reliable. Possibly not an appropriate version of main module is used or an illegal connection was made up.

Version history

v1.19

(c) When bAlternateTrapUID = FALSE
- Welcome alarm severity changed from INF to CEA and has the same UID what used at program exit.
- Shut down alarm severity changed from WAR to CRI and has a unique UID what will be used at program start.
(n) New INI entry: [Advanced]/uiGoodByeTrapUID; saved at module shut down and used at start up in the CEA alarm

v1.18

(n) SCCP routing based on SCCP.CapPA.GT to minimize the cross-MSS traffic.
(n) New INI entry: [SCCP routing preferences]/bForced; default value is 'False'
(n) New INI entry: [SCCP routing preferences]/SCCP.CadPA.GTprefix = RL.DPC

v1.17

(c) 5 MSUSs are sent in each thread cycle instead of the former 1.
(n) Indication of maximum value of circlular TCP-to-SCTP buffer ("RxBuffered").

v1.16

(c) SGA file period can be set.
(n) New INI entry: [SGAfiles]/dwFilePeriodMin.

v1.15

(n) Optional Up/Down signal from/to the application module through TCP connection.
(n) New INI entry: [RemoteRequest]/bForwardUpDownSignal.

v1.14

(n) SLS-based routing for outgoing MSUs.
(n) New INI entry: [SS7]/bApplyRouteSeparationBasedOnSLS; default value is 'False'

v1.13

(n) Disconnection of associations in indicated in SGA file.

v1.12

(n) M3UA/ASPDN and M3UA/ASIA can be send manually (Debug menu).
(n) New state of ASP: 'ASP up' is already received but 'ASP active' has not yet arrived.

v1.11

(n) Value of Delayed acknowledgement (SACK delay) is now adjustable.
(n) New INI entry: [SCTP]/dwDelayedACKmsec.

v1.10

(n) M3UA (SS7) content is optionally written into daily binary files.
(n) New INI entry: [SGAfiles]/sFilesPath.
(n) New INI entry: [SGAfiles]/sFileNamePrefix.
(n) New INI entry: [SGAfiles]/sSigLinkID.

v1.09

(n) New alarms are introduced to indicate MSU forwarding problems towards the logical module.

v1.08

(n) Configurable unique caption text.
(n) New INI entry: [Advanced ]/sID.

v1.07

(c) Handles different behaviours of different realizations of SCTP peers.

v1.06

(c) Slight changes in SNMP tarp generating related to establishment and breakdown of SCTP associations.

v1.05

(n) Configurable DSCP field in IP layer.
(n) New INI entry: [SCTP]/byIPfieldDSCP.

v1.04

(n) Optional fixed routing towards the neighbour equipments.
(n) New INI entry: [SS7]/bNoAlternateRouteForNeighbours; possible values:

v1.03

(f) More stable connection handling in case of extreme high transmission traffic.

v1.02

(n) Configurable client-server mode.
(n) New INI entry: [SCTP]/byClientServerMode; possible values:

v1.01

(c) Now incoming SCTP INIT messages are suppressed.
(c) Slight changes in SNMP tarp generating related to establishment and breakdown of SCTP associations.