Unique GTT Selectors

In previous EAGLE releases that did not support the Unique GTT Selectors feature, all ITU GTT selectors shared the same space in the GTT selector table. Only one entry for an ITU GTT selector that contains a specific GTI and translation type value, regardless of the network type or domain of the ITU GTT selector, could be defined in the GTT selector table. For example, if the GTT selector table contained an ITU-I GTT selector with the GTI value 2 and the translation type value 5, this GTI and translation type value combination could not be assigned to an ITU-N or ITU-N24 GTT selector.

When the EAGLE is upgraded from a release that did not support the Unique GTT Selectors feature to a release that does support the Unique GTT Selectors feature, the ITU GTT selectors created in the previous release become overlapped GTT selectors.

The Unique GTT Selectors feature does not allow overlapped GTT selectors to be provisioned in the GTT selector table. All new GTT selectors that are created in the release that supports the Unique GTT Selectors feature are non-overlapped GTT selectors. The Unique GTT Selectors feature allows for ITU GTT selectors to be provisioned with these attributes.

• ITU-I spare and ITU-N spare GTT selectors
• Provisioning the same translation type and GTI values for ITU GTT selectors of all network types including the ITU-I spare and ITU-N spare network types.
• GTT selectors of all network types including ITU-I spare and ITU-N spare network types that contain the GTI value 0 (zero).

In a release that does support the Unique GTT Selectors feature, the user is able to add more GTT Selectors for the existing overlapped GTT Selector as long as the GTIx (ITU domain only) and TT combination matches the existing overlapped GTT Selector.

The user will not be able to add a new non-overlapped GTT selector entry if the GTIx (ITU domain only) and TT combination matches to an existing overlapped GTT Selector entry created during upgrade to a release that supports the Unique GTT Selectors feature from a release that did not support it. The unqgttsel parameter in the SCCPOPTS table controls run-time behavior of the Unique GTT Selector feature; when it is set to "exactmatch," overlapped entries will behave as non-overlapped entry.

Any new entries added in a release that supports the Unique GTT Selectors feature, with the GTIx and TT combination that were not present in the system while upgrading to a release that supports the Unique GTT Selectors feature, will be added as non-overlapped entries.

The provisioning of ITU-I spare and ITU-N spare GTT selectors is the same as provisioning ITU-I and ITU-N GTT selectors. This includes the provisioning of default GTT selectors using the ent-tt command. For more information about using the ent-tt command to provision default GTT selectors, see the Adding a Translation Type procedure.

GTT Selectors with the GTI Value of 0

With the Unique GTT Selectors feature, The EAGLE can process MSUs whose GTI value is 0 (a GTI=0 GTT selector) for all network types, including ITU-I spare and ITU-N spare. A GTI=0 GTT selector cannot contain tt, np, nai, and Eagle-Gen values. A GTI=0 GTT selector can contain lsn (the name of a linkset), selid, and cgssn values. The values that can be specified for a GTI=0 GTT selector is determined by the features that are enabled and turned on.

GTT Selector Key for GTI=0 GTT Selectors

Table 2-21 defines the keys in the GTT selector table based on the feature combination for GTI=0 GTT selectors. If a feature supports specific parameters and that feature is not enabled or turned on, then default values are entered into the database for those parameters.

Table 2-21 GTT Selector Key for GTI=0

Feature Combination	Selector Type	GTI, Domain	CgPA SSN	SELID	Link Set Name
EGTT	CdPA Only	X	-	-	-
Origin-Based SCCP Routing	CdPA	X	-	-	-
	CgPA	X	X	X	-
Flexible Linkset Optional Based Routing	CdPA	X	-	X	X
	CgPA	X	-	X	X
Origin-Based SCCP Routing and Flexible Linkset Optional Based Routing	CdPA	X	-	X	X
	CgPA	X	X	X	X

Searching Order for GTI=0 GTT Selectors

Table 2-22 and Table 2-23 shows the searching order for CdPA and CgPA GTI=0 GTT Selectors.

Table 2-22 Searching Order for CdPA GTI=0 GTT Selectors

CdPA GTT Selector Keys
Priority	GTA, Domain	Linkset ID	SELID	CdPA GTT Selector Found or Not Found
1	Exact	Exact	Exact	If a meaningful CdPA GTT set is provisioned, then the GTT selector is considered found. If a meaningful CdPA GTT set is not provisioned, then the GTT selector is considered not found.
2	Exact	Any	Exact

Table 2-23 Searching Order for CgPA GTI=0 GTT Selectors

CgPA GTT Selector Keys
Priority	GTA, Domain	Linkset ID	SELID	CgPA SSN	CgPA GTT Selector Found or Not Found
1	Exact	Exact	Exact	Exact	If a meaningful CgPA GTT set is provisioned, then the GTT selector is considered found. If a meaningful CgPA GTT set is not provisioned, then the GTT selector is considered not found.
2	Exact	Exact	Exact	Any
3	Exact	Any	Exact	Exact
4	Exact	Any	Exact	Any
5	Exact	Any	Any	Any

For the Origin-Based SCCP Routing feature GTT hierarchy, meaningful means following the Origin-Based SCCP Routing feature rules; the GTT set type of a CdPA GTT set must be CDGTA and the GTT set type of a CgPA GTT set must be either CGGTA or CGPC. If a Flexible Linkset Optional Based Routing feature GTT hierarchy is being used, then any GTT set type can be used.

The Linkset ID, SELID, and CGSSN parameters are controlled by the Flexible Linkset Optional Based Routing and Origin-Based SCCP Routing features. If a parameter is not allowed, it assumes the value of Any in the database. In Table 2-22 and Table 2-23, if a parameter is specified as Exact and that parameter is not allowed, then the Exact value is the same as the Any value.

Using the Unique GTT Selectors Feature

To determine how a GTT selector search is performed on overlapped GTT selectors, the unqgttsel parameter of the chg-sccpopts command is used. The unqgttsel parameter contains these values.

• bestmatch - search for overlapped GTT selectors if non-overlapped GTT selectors are not found.
• exactmatch - search only for non-overlapped GTT selectors.

When the unqgttsel parameter is applied to GTIx=2 and GTIx=4 GTT selectors, these actions occur.

• When the unqgttsel parameter value is bestmatch:
  • A non-overlapped GTT selector is matched, if it is in the database, using the searching rules defined by the EGTT, Origin-Based SCCP Routing features, Flexible Linkset Optional Based Routing, and TCAP Opcode Based Routing features.
  • If a non-overlapped GTT selector is not found, an overlapped GTT selector is matched, if it is in the database, using the searching rules defined by the EGTT, Origin-Based SCCP Routing features, Flexible Linkset Optional Based Routing, and TCAP Opcode Based Routing features.
  • If a matching non-overlapped or overlapped GTT selector is not found, the search fails.
• When the unqgttsel parameter value is exactmatch:
  • A non-overlapped GTT selector is matched, if it is in the database.
  • If a matching non-overlapped GTT selector is not found, the search fails.

When the unqgttselparameter is applied to GTIx=0 GTT selectors, these actions occur.

• When the unqgttsel parameter value is bestmatch:
  • An exact GTIx=0 GTT selector is matched, if it is in the database, using the searching order shown in Table 2-22 and Table 2-23.
  • If an exact GTIx=0 GTT selector match is not found, an overlapped GTT selector (ANSI and ITU-I network types only) is matched, if it exists, using the searching order shown in Table 2-22 and Table 2-23.
  • If an exact GTIx=0 GTT selector match is not found and an overlapped GTT selector is not found, the search fails.
• When the unqgttsel parameter value is exactmatch:
  • An exact GTIx=0 GTT selector is matched, if it is in the database, using the searching order shown in Table 2-22 and Table 2-23.
  • If an exact GTIx=0 GTT selector match is not found, the search fails.

The unqgttsel parameter value can be changed at any time. Non-overlapped GTT selectors can be provisioned regardless of the unqgttsel parameter value. When there are no overlapped GTT selectors in the database and only non-overlapped GTT selectors are in the database, the exactmatch value of the unqgttsel parameter is applied to the GTIx=2 and GTIx=4 GTT selectors. The system default value of the unqgttsel parameter is bestmatch.