MTP LEVEL 3
TEST NUMBER:	3.16	PAGE:	1 of 1		
REFERENCE:	Q.704 § 5 Fig. 28, Fig. 29, Fig. 30			
TITLE:	Changeover			
SUBTITLE:	Changeover to another linkset with adjacent SP accessible			
PURPOSE:	To check that the system performs changeover to an alternative route when the last link of a linkset becomes unavailable			
PRE–TEST CONDITIONS:	Linkset 1 and link 3 – 1 unavailable			
CONFIGURATION:	B	TYPE OF TEST:	VAT, CPT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A	SP	B	SP	C		SP		·	
Link	Link	Link		Link	
:Start traffic			
  3 – 2		TRAFFIC	 ------------------------------------->	7 – 1	 -------------->			SP		E	
	8 – 1	<--------------		SP		D	
	<------------------------------------	3 – 2	<--------------		 7 – 1		SP		E	
2 – 1, 2	TRAFFIC		- --------------->	6 – 1	 ------------------------------------------->	SP		E	
					5 – 1	 ------------------------------------------->	SP 		D	
				<---------------	2 – 1, 2	<-------------------------------------------	5 – 1	SP		  D	
3 – 2	:Deactivate (MML command or failure)		
2 – X	COO, SLC	---------------->	4 – 1
	3 – 2	 -------------->	
				<--------------	2 – X	<--------------4 – 1 COA, SLC 3 – 2	
2 – 1, 2	TRAFFIC		 --------------->	6 – 1	------------------------------------------->		SP		E	
	(from 3 – 2)		5 – 1	 ------------------------------------------>		SP		D	
				<---------------	2 – 1, 2	<-----------------------------------------	  5 – 1	SP		D	
				<---------------	2 – 1, 2	<-----------------------------------------	  6 – 1	SP		E	
:Wait			
:Stop traffic			
			
TEST DESCRIPTION			
1.	Start traffic to E (and D in VAT).		
2.	Deactivate link 3 – 2 and check that a COO (for 3 – 2) is sent from A to C via B and that a COA (from 3 – 2) is sent from C to A via B within T2.		
3.	Stop traffic and check that it has been shared on the alternative links 2 – 1 and 2 – 2 according to the load sharing rules of linkset 2.		
4.	Check that, for each SLS, there was no lost messages, no duplication and no missequencing.		
5.	Repeat the test but replace COO with ECO (some messages may have been lost).		

MTP LEVEL 3
TEST NUMBER:	3.17	PAGE:	1 of 1		
REFERENCE:	Q.704 § 5 Fig. 28, Fig. 29, Fig. 30			
TITLE:	Changeover			
SUBTITLE:	Changeover to another linkset with adjacent SP inaccessible			
PURPOSE:	To check that the system responds correctly when there is no path between the ends of an unavailable link.			
PRE–TEST CONDITIONS:	Linkset 4 unavailable			
CONFIGURATION:	B	TYPE OF TEST:	VAT, CPT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A	SP	B	SP	C	SP	E	
Link	Link	Link			Link	
:Start traffic			
2 – 1	TRAFFIC	 -------->	6 – 1	 -------------------------------------->	
2 – 2	TRAFFIC	 -------->	6 – 1	 --------------------------------------->	
3 – 1	TRAFFIC	 ------------------------------------>	7 – 1	 -------------->	
			<----------------------------------	3 – 1	<--------------	7 – 1	TRAFFIC	
3 – 2	TRAFFIC	 ------------------------------------>	7 – 1	 -------------->	
			<----------------------------------	3 – 2	<-------------	7 – 1	TRAFFIC	
2 – 1	:Deactivate (MML command or failure)			
2 – 2	:Deactivate (MML command or failure)			
	½
	½
	½T1
	½
	½			
3 – 1	TRAFFIC	 ------------------------------------>
	(from 2 – 1, 2)	7 – 1	 ------------->	
			<-----------------------------------	3 – 1	<-------------	7 – 1	TRAFFIC	
3 – 2	TRAFFIC	 ------------------------------------>
	(from 2 – 1, 2)	7 – 1	 ------------->	
			<-----------------------------------	3 – 2	<-------------	7 – 1	TRAFFIC	
:Wait			
:Stop traffic			
			
TEST DESCRIPTION			
1.	Start traffic to E on linkset 2 and 3.		
2.	Deactivate the linkset 2.		
3.	Check that traffic continues on linkset 3 at the expiration of T1.		
4.	Stop traffic and check that it has been shared on links 3 – 1 and 3 – 2 according to the load sharing rules of the linkset 3.		
5.	Check that the traffic has been received correctly. Some messages may have been lost but none should be missequenced or duplicated..		
6.	Check that the duration of T1 is inside the specified range.		

MTP LEVEL 3
TEST NUMBER:	3.18	PAGE:	1 of 1		
REFERENCE:	Q.704 § 5 Fig. 28, Fig. 29, Fig. 30			
TITLE:	Changeover			
SUBTITLE:	Changeover to two linksets			
PURPOSE:	To check the changeover procedure when it is performed to several links pertaining to two linksets			
PRE–TEST CONDITIONS:	Link 1 – 1 unavailable, all other available			
CONFIGURATION:	B	TYPE OF TEST:	VAT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A	SP	B	SP	C	SP	D	
	Link	Link	Link		Link	
:Start traffic			
	1 – 2	TRAFFIC	------------------------------------------------------------------->		
	<------------------------------------------------------------------		1 – 2	TRAFFIC	
	1 – 2	:Deactivate (MML command or failure)			
	2 – X	COO,
			SLC 1 – 2	 -------->  5 – 1   ---------------------------------------------->		
or 3 – X	---------------------------------------->   8 – 1    ------------->		
	<--------  2 – X  <---------------------------------------------		5 – 1	COA,
			SLC 1 – 2	
	2 – 1	TRAFIC
			(from 1 – 2)	 -------->  5 – 1   ---------------------------------------------->		
	<--------  2 – X  <---------------------------------------------		5 – 1	TRAFIC
			(from 1 – 2)	
	2 – 2	TRAFIC
			(from 1 – 2)	 -------->  5 – 1   ---------------------------------------------->		
	3 – 1	TRAFFIC
			(from 1 – 2)	 --------------------------------------->   8 – 1    -------------->		
	3 – 2	TRAFFIC
			(from 1 – 2)	 --------------------------------------->   8 – 1    -------------->		
:Wait			
:Stop traffic			
			
TEST DESCRIPTION			
1.	Start traffic to D.		
2.	Deactivate the link 1 – 2 and check that a COO for 1 – 2 is sent to D via B or C and that a COA is sent from D to A via B or C inside T2.		
3.	Stop traffic and check that it has been shared on the alternative links 2 – 1, 2 – 2, 3 – 1 and 3 – 2 according to the load sharing rules in A.		
4.	Check that, for each SLS, there were no lost messages, no duplication and no missequencing.		
5.	Repeat the test but replace COO with ECO (some messages may have been lost).		

MTP LEVEL 3
TEST NUMBER:	3.19	PAGE:	1 of 1		
REFERENCE:	Q.704 § 5 ; 3.2.2			
TITLE:	Changeover			
SUBTITLE:	Changeover due to various reasons			
PURPOSE:	To check the interface L2–L3			
PRE–TEST CONDITIONS:	Linkset with two available links			
CONFIGURATION:	A	TYPE OF TEST:	VAT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A		SP	B	
	Link		Link	
:Start traffic			
	1 – 1	TRAFFIC	------------------->		
	<-----------------	1 – 1	TRAFFIC	
	1 – 2	TRAFFIC	------------------->		
	<-----------------	1 – 2	TRAFFIC	
	1 – 1		:Deactivation due to various reasons (see Note)			
	CHANGEOVER			
	1 – 2	TRAFFIC
			(from 1 – 1)	------------------->		
	<-----------------	1 – 2	TRAFFIC (from 1 – 1)	
:Wait			
:Stop traffic			
			
Note – The object of this test is to check the interface L2–L3 by invoking a changeover by the different means listed in Q.704 (§ 3.2.2). These reasons are: high error rate, expiration of timer T1, T2, T6 and T7 of L2, equipement failure, erroneous BSN or FIB, reception of SIOS, SIN, SIE, SIO and SIPO of L2, and management request. The goal of this test is not to check the changeover procedure itself, but only that the COO is generated for each of these reasons.			
			
TEST DESCRIPTION			
1.	Start traffic to B and C on all links.		
2.	Invoke the deactivation of the link 1 – 1 (see Note above).		
3.	Check that traffic is changed over from 1 – 1 to 1 – 2.		
4.	Stop traffic and check that it has been received correctly.		
5.	Repeat the test for each reason.		

MTP LEVEL 3
TEST NUMBER:	3.20	PAGE:	1 of 1		
REFERENCE:	Q.704   § 5,   Fig. 28, Fig. 29, Fig. 30			
TITLE:	Changeover			
SUB TITLE:	Changeover as compatibility test			
PURPOSE:	To check the changeover procedure as compatibility test			
PRE–TEST CONDITIONS:	Linkset with two available links			
CONFIGURATION:	A	TYPE OF TEST:	CPT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A		SP	B	
	Link		Link	
:Start traffic			
	1 – 1	TRAFFIC	------------------------->		
	<------------------------	1 – 1	TRAFFIC	
	1 – 2	TRAFFIC	------------------------->		
	<------------------------	1 – 2	TRAFFIC	
	1 – 1	:Deactivate (MML command or failure)			
	CHANGEOVER			
	1 – 2	TRAFFIC (from 1 – 1)	------------------------->		
	<------------------------	1 – 2	TRAFFIC (from 1 – 1)	
:Wait			
:Stop traffic			
Note – In a compatibility test it is impossible to describe precisely the exchanges of changeover messages because the description depends of the type of deactivation of the link and of the time necessary to detect the deactivation.			
			
TEST DESCRIPTION			
1.	Start traffic to B on links 1 – 1 and 1 – 2.		
2.	Deactivate link 1 – 1 and check that the changeover is performed.		
3.	Check that the sequence of changeover messages conforms to one of the descriptions 3.1 to 3.12. Stop traffic.		
4.	Repeat the test by invoking the different reasons listed in the note in test 3.19.		

MTP LEVEL 3
TEST NUMBER:	3.21	PAGE:	1 of 1		
REFERENCE:	Q.704   § 5,   Fig. 28, Fig. 29, Fig. 30			
TITLE:	Changeover			
SUB TITLE:	Reception of a changeover order on an available link			
PURPOSE:	To check the changeover procedure on reception of a COO or ECO for a link in service			
PRE–TEST CONDITIONS:	Linkset with two available links			
CONFIGURATION:	A	TYPE OF TEST:	VAT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A		SP	B	
	Link		Link	
:Start traffic			
	1 – 1		TRAFFIC	------------------------->		
	<------------------------	1 – 1	TRAFFIC	
	1 – 2	TRAFFIC	 ------------------------->		
	<------------------------	1 – 2	TRAFFIC	
	<------------------------	1 – 2	COO, SLC 1 – 1
	(FSN corresponding to the last 	received message)	
	1 – 2		COA, SLC 1 – 1	------------------------->		
	1 – 2		TRAFFIC (from 1 – 1)	 ------------------------->		
	<------------------------	1 – 2	TRAFFIC (from 1 – 1)	
:Wait			
:Stop traffic			
			
TEST DESCRIPTION			
1.	Start traffic to B and C on all the links.		
2.	Send a COO from B to A for 1 – 1 on link 1 – 2 and check that the COA is received.		
3.	Check that the link 1 – 1 becomes unavailable.		
4.	Stop traffic and check that the changeover procedure has been performed.		
5.	Check that there was no loss of messages, no duplication and no missequencing.		
6.	Repeat the test but send an ECO (instead of a COO) and check that an ECA is received (instead of a COA). Some messages may be lost.		

MTP LEVEL 3
TEST NUMBER:	4.1	PAGE:	1 of 1		
REFERENCE:	Q.704   § 6,   Fig. 28, Fig. 29, Fig. 31			
TITLE:	Changeback			
SUB TITLE:	Changeback within a linkset			
PURPOSE:	To check that the changeback procedure is correctly performed on restoration of a link in a linkset			
PRE–TEST CONDITIONS:	Linkset with one available link (end of test 3.1)			
CONFIGURATION:	A	TYPE OF TEST:	VAT, CPT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A		SP	B	
	Link		Link	
:Start traffic			
	1 – 2		TRAFFIC	------------------------->		
	<------------------------	1 – 2		TRAFFIC	
	1 – 1	:Activate (depending of the deactivation mean previously used)	
	1 – 2	CBD, SLC 1 – 1	------------------------->		
	<------------------------	1 – X	CBA, SLC 1 – 1	
	1 – 1	TRAFFIC (from 1 – 2)	 ------------------------->		
	<------------------------	1 – 2	CBD, SLC 1 – 1	
	1 – X	CBA, SLC 1 – 1	 ------------------------->		
	<------------------------	1 – 1	TRAFFIC (from 1 – 2)	
	1 – 2	TRAFFIC	 ------------------------->		
	<------------------------	1 – 2	TRAFFIC	
:Wait			
:Stop traffic			
			
TEST DESCRIPTION			
1.	Start traffic to B (and C in VAT) on link 1 – 2.		
2.	Activate the link 1 – 1 and check that it enters the correct in service state.		
3.	Check that a CBD for SLC 1 – 1 is received and that traffic for link 1 – 1 is switched back after a CBA is sent.		
4.	Stop traffic and check that it has been received correctly, no lost messages, no duplication and no missequencing.		
5.	Continue the test by activating the link 1 – 3, then 1 – 4.		
6.	As a compatibility test, repeat the test for several reasons chosen among those listed in test 4.10.		

MTP LEVEL 3
TEST NUMBER:	4.2	PAGE:	1 of 1		
REFERENCE:	Q.704   § 6,   Fig. 28, Fig. 29, Fig. 31			
TITLE:	Changeback			
SUB TITLE:	Additional CBA			
PURPOSE:	To check the actions of the system on reception of an additional CBA			
PRE–TEST CONDITIONS:	Linkset with all links available			
CONFIGURATION:	A	TYPE OF TEST:	VAT	TYPE OF SP:	ALL	
MESSAGE SEQUENCE:			
SP	A		SP	B	
	Link		Link	
:Start traffic			
	ALL	TRAFFIC	 ------------------------->		
	<------------------------	ALL		TRAFFIC	
	<------------------------	1 – X		CBA, SLC 1 – X	
	ALL		TRAFFIC	 ------------------------->		
	<------------------------	ALL		TRAFFIC	
:Wait			
:Stop traffic			
			
TEST DESCRIPTION			
1.	Start traffic to B and C on all links.		
2.	Send an unexpected CBA to A and check that this message is discarded without action on the traffic.		
3.	Stop traffic.