Telecommunications - Configuration of Closed user group

 

Subscription Option - Closed user group

Subscription Option - Closed user group with Outgoing Access

Subscription Option - Closed user group with Incoming Access

Subscription Option Incoming Calls Barred within a closed user group

Subscription Option Outgoing Calls Barred within a closed user group


A closed user group ( ) permits the DTEs belonging to the closed user group to communicate with each other but precludes communication with other users.

Each member of the CUG identifies it with a local CUG ID (1-99).

Support:

UK(a) UK(b)
Closed User Group supported supported
(although validation can be done without using CUGs if required.
max CUGs per line 99 99
preferential CUG CUG number 1 if outgoing access is subscribed this will in effect be the preferential CUG
Can a CUG be no. a CUG is no. a CUG is
associated with an associated with a associated with a
individual subaddress physical port physical port

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
Closed user group (CUG)............. 1.12 E

| Closed user group (CUG).............| 1.12 E |

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10.15 - Subscription Option - Closed user group with Outgoing Access

Enables a DTE to belong to one or more closed user groups and to originate calls to DTEs in the open part of the network.

When the closed user group with outgoing access facility is subscribed to and the DTE has a default CUG (known as a preferential CUG) then only the closed user group selection facility is applicable for use at the interface.

When the closed user group with outgoing access facility is subscribed to and the network offers to the DTE the capability of choosing whether or not to have a preferential CUG and the DTE has no preferential CUG, then both the closed user group facility and the closed user group with outgoing access facility are applicable.

UK(a) - supported only as a preferential CUG

UK(b) - supported

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
CUG with outgoing access............ 1.13 A p p

| CUG with outgoing access............| 1.13 A | | |

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10.16 - Subscription Option - Closed user group with Incoming Access

Description of Option

Enables the DTE to belong to one or more closed user groups and to receive incoming calls from DTEs in the open part of the network.

When the closed user group with incoming access facility is subscribed to and the DTE has a , then only the closed user group selection facility is applicable for use at the interface.

When the closed user group with incoming access facility is subscribed to and the network offers to the DTE the capability of choosing whether or not to have a preferential CUG and the DTE has no preferential CUG, then both the closed user group facility and the closed user group with outgoing access facility are applicable.

UK(a) - supported

UK(b) - supported

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
CUG with incoming access............ 1.14 A p

| CUG with incoming access............| 1.14 A | | |

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10.17 Subscription Option Incoming Calls Barred within a closed user group

Permits the DTE to originate virtual calls to DTEs in this closed user group, but precludes the reception of incoming calls from DTEs in this closed user group.

UK(a) - not supported

UK(b) - supported

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
Incoming calls barred within CUG.... 1.15 A .

| Incoming calls barred within CUG....| 1.15 A | . |

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10.18 Subscription Option Outgoing Calls Barred within a closed user group

Description of Option

Permits the DTE to receive virtual calls from DTEs in this closed user group, but prevents the DTE from originating calls to DTEs in this closed user group.

UK(a) - not supported

UK(b) - supported

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
Outgoing calls barred within CUG.... 1.16 A .

| Outgoing calls barred within CUG....| 1.16 A | . |

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\info\computer\UK\x25-sub\cug-t.t1

Closed user group with outgoing access facility

When the closed user group with outgoing access facility is subscribed to and the DTE has a default CUG (known as a preferential CUG) then only the closed user group selection facility is applicable for use at the interface.

When the closed user group with outgoing access facility is subscribed to and the network offers to the DTE the capability of choosing whether or not to have a preferential CUG and the DTE has no preferential CUG, then both the closed user group facility and the closed user group with outgoing access facility are applicable.

When the closed user group with incoming access facility is subscribed to and the DTE has a , then only the closed user group selection facility is applicable for use at the interface.

When the closed user group with incoming access facility is subscribed to and the network offers to the DTE the capability of choosing whether or not to have a preferential CUG and the DTE has no preferential CUG, then both the closed user group facility and the closed user group with outgoing access facility are applicable.

&UKa& = yUKa support

DX1: yes

DX2: yes

TP4/III: ?

UKa already support closed user groups in current release, I know of no changes for release 4.

Each member of the CUG identifies it with a local CUG ID (1-99) but internally to the network the CUG is represented by a CUG interlock code. This is a number in the range 1-32767, Public Network allocates numbers from the bottom up. 32767 is the wildcard and should not be used for security reasons.

Limitations are:

* maximum of 99 CUGs per line

* CUG subscriptions always apply to whole line (even if multiple address are defined for the line).

* CUG number 1 is always preferential CUG

The lines to which the CUG applies are specified using the 'base' NUA of the lines.

Table build questions:

TNDTED Q234(was Q121) cug member

|TNDTED Q234| Q121 | cug member..........................#This question is used to indicate whether the DTE is actually a member of a CUG or whether the XLB entry is being used for TAMS. Details of CUG are entered using NUICUG program.

TNDTED Q210(was q98 ) DTE sending interlock code facility

|TNDTED Q210| q98 | DTE sending interlock code fac......#(YES/NO)

default NO

This question indicates that the DTE may send Interlock Codes in call request packets.

This question is always set to NO on Public Network - on no account should it be set to YES as it could compromise network security.

TNDTED Q211(was q99 ) DTE receiving interlock code facility

|TNDTED Q211| q99 | DTE receiving interlock code fac...#(YES/NO)

default NO

This question indicates that the DTE may receive Interlock Codes in call request packets. This question is always set to NO on Public Network - on no account should it be set to YES as it could compromise network security.

CUG details are entered using the NUICUG program. The following options are set:

01 NUI: for X.25 lines this is <last 8 digits of NUA> @
03 Start date:
04 Format: internal format of tables:
Format 0 = no cugs
Format 1 = one cug
Format 2 = two cugs
Format 3 = more than two cugs
09 CUG outgoing access
10 CUG incoming access
11 NUA: NUA used for billing
12 Default CUG: eg preferential CUG
13 CUG names: interlock code followed by optional string in ADD mode:
<CUG name>
SAME AS <NUI name>
NO
END
<cr>
in CHANGE mode:
+<CUG name>
-<CUG name>
-ALL
14 NAP names Network Access Point for TP concerned.

the 'NUI' is crunched by the program into a unique NUC.

see X.75 section for entering ICUGs

UKa Answers

Question: Can a CUG be specified on a particular subaddress, but not on

the whole line?

Answer : No.

UKa Answers

Question: can a CUG be specified on a Multiline/hunt group?

Answer : No, This can only be done by giving all the specific addresses in the NUI/CUG program.

&UKb& = yUKb support

v 4.03

RD 0004 part 8:1.C (PICS proforma Public Network1984)

FS3b - CUGCUGCUGCUG selection - basic format ........ O = Optional

FS3e - CUG selection - extended format ...... P = Prohibited

FR3b - CUG selection - basic format ........ O = Optional

FR3e - CUG selection - extended format ...... P = Prohibited

Release 4 is compatible with ONA for this option.

Test plan and implementation issues

no changes.

UKa provides partial support, in that CUG with outgoing access is supported, but the user cannot have a preferential CUG with this option. Therefore the closed user group with outgoing access facility is not used. (ie the open network is the only default allowed).

Table build questions:

TNDTED Q234(was Q121) cug member

|TNDTED Q234| Q121 | cug member..........................#This question is used to indicate whether the DTE is actually a member of a CUG or whether the XLB entry is being used for TAMS. Details of CUG are entered using NUICUG program.

No change at release 4

&UKb& = yUKb support

v 4.03

SVC: yes

PVC: n/a

X.32: no

Turbo Engine:

Mini Engine:

Micro Engine:

Pico Engine:

&telematics& = yTelematics support

yes supported

&internal& = y

CCITT compatibility

X.2 1984 ... A - additional service

X.2 1988 ... A - additional service

ISO 8878 compatibility

ONA compatibility

RD 0004 part 8:1.C (PICS proforma Public Network1984)

FS4b - CUG selection with outgoing access

- basic format ........ O = Optional

FS4e - CUG selection with outgoing access

- extended format ...... P = Prohibited

FR4b - CUG selection with outgoing access

- basic format ........ O = Optional

FR4e - CUG selection with outgoing access

- extended format ...... P = Prohibited

Public Network cannot accept CUG selection with O/G access.

Test plan and implementation issues

&UKa& = yUKa support

DX1: partial

DX2: partial

TP4/III: ?

UKa provides partial support in that CUG with incoming access is supported, but the user cannot have a preferential CUG. Therefore the closed user group with outgoing access facility is not used.

Table build questions:

TNDTED Q234(was Q121) cug member

|TNDTED Q234| Q121 | cug member..........................#This question is used to indicate whether the DTE is actually a member of a CUG or whether the XLB entry is being used for TAMS details of CUG are entered using NUICUG program.




10.19 - Subscription Option - Bilateral Closed User Groups

10.20 Subscription Option Bilateral Closed User Groups with outgoing Access


Description of Option

Enables pairs of DTEs to form bilateral relations allowing access between each other while excluding access to or from other DTEs with which such a relation has not been formed.

A DTE may belong to one or more BCUGs. Different combinations of access restrictions for DTEs having these facilities result in various combinations of accessibility.

When a bilateral closed user group facility is used the called DTE address is not used, because the network can identify the remote DTE from the BCUG information. This provides a form of' short code addressing'.

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
Bilateral closed user group......... 1.17 A . . . . .

| Bilateral closed user group.........| 1.17 A | . | . | . | . | . | | #


10.20 Subscription Option Bilateral Closed User Groups with outgoing Access

Description of Option

As for Bilateral Closed User Group but also allows access to the open part of the network.

For a given BCUG, it is permissible for one DTE to subscribe to the BCUG facility while the other subscribes to the BCUG with outgoing access facility.

X.2 LEVEL 3 PER USER SUBSCRIPTION X.2 (1984) UK(a) UK(b) interworking
OPTIONS REF CLASS now now R5a R5b R6
Bilateral CUG with outgoing access.. 1.18 A . . . . .

| Bilateral CUG with outgoing access..| 1.18 A | . | . | . | . | . | | #


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