Isdn - Avaya Support

Transcript

Integrated Services Digital Network (ISDN)

This page gives details on our ISDN connections and the ETSI call clear codes.

All Network Alchemy products connect to the Public Network using Integrated Services Digital Network (ISDN), we do not support analogue connections.

The products support Basic Rate Interface (BRI) which is 2 channels per line, and Primary Rate Interface (PRI) which is up to 30 channels per line.

The CyberGear has one BRI connection, The ArgentOffice can have either 2 x BRI lines (ArgentOffice4), or 4 x BRI lines (ArgentOffice8), or 1 x PRI line (ArgentOffice30).

The products are designed to the EuroISDN standards - ETSI TBR3 (BRI) and TBR4 (PRI).

When using a PRI connection CRC4 error checking is enabled - as required by ETSI - we do not have an option to disable this. PRI lines are always Point-toPoint.

The BRI lines can be used in either Point-to-Point or Point-to-MultiPoint mode. Point-to-Point lines are used when only one device terminates a line in a customers office. Point-to-MultiPoint lines are used when more than one device may be used on the line at the customers premises.

There are major benefits in using Point-to-Point lines: -

1. The exchange knows when the line/ terminal equipment is down/ dead, thus it will not offer calls down that line. If the lines are Point-to-MultiPoint calls will always be offered down the line and will fail if no response from the terminal equipment. So if you have two Point-to-MultiPoint lines and one is faulty 50% of incoming calls will fail.
2. You get a Green LED on the CyberGear/ ArgentOffice when the line is connected. With Point-to-MultiPoint lines some exchanges e.g. BT's ISDN2e will drop level/ layer 1/ 2 signals when the line is idle for a period.
3. The ArgentOffice timing clock is locked to the exchange. If level/ layer 1/ 2 signals disappear on a line then the ArgentOffice will switch to another line, however this may result in some audible click when the switchover occurs.

BT supply single ISDN lines (ISDN2/ ISDN2e/ HomeHighway/ BusinessHighway) as Point-to-MultiPoint lines. If you order Direct Dial In (DDI) numbers across multiple lines then they will be provided as Point-to-Point lines. There is no sales option for Point-to-Point/ Point-to-MultiPoint although a BT engineer can change this option.

The CyberGear/ ArgentOffice products will typically work when defaulted on either Point-to-Point or Point-to-MultiPoint lines. This is because our Terminal Equipment Identifier (TEI) ,which is used by the exchange to chat to the equipment, is set to 0 (TEI = 0). If you intend to connect multiple devices (simultaneously) to an ISDN line then the TEI should be set to 127. With a TEI = 127 the CyberGear/ ArgentOffice will ask the exchange to allocate a TEI for operation.

NOTE :- When connected to some manufactures equipment which provides an 'S0 interface' (BRI) a defaulted CyberGear/ ArgentOffice will not bring up the ISDN line. Configuring  the unit to a  TEI = 127 for that line will typically resolve this.

BT currently provide ISDN  BRI service in 3 flavors. The following is an attempt to clarify their offerings.

HomeHighway

Line is terminated by box provided by BT which requires mains power.

It has 2 analogue ports. These can have full range of "Select Services" e.g. Caller Display, Call Waiting, Call forwarding, 1471, etc.

It has 2 digital (ISDN) ports. No "Supplementary Services" are available. This means no MSN, CLIP etc.

Switchboard connection is not permitted i.e. no DDI or ISDN Point to Point operation.

Only 2 simultaneous call are permitted on the line.

Distance from the exchange is shorter that ISDN2e due to the need to ring the telephones on port 1 if mains power fails.

BusinessHighway

Line is terminated by box provided by BT which requires mains power.

It has 2 analogue ports. These can have full range of "Select Services" e.g. Caller Display, Call Waiting, Call forwarding, 1471, etc.

It has 2 digital (ISDN) ports. The full range of "Supplementary Services" are available. e.g. MSN, CLIP, Administrative Call forwarding etc.

Switchboard connection is not permitted i.e. no DDI or ISDN Point to Point operation.

Only 2 simultaneous call are permitted on the line.

Distance from the exchange is shorter that ISDN2e due to need to ring the telephones on port 1 if mains power fails.

ISDN2e

Line termination box does NOT require mains supply.

No analogue ports

It has 2 ISDN ports. The full range of "Supplementary Services" are available. e.g. MSN, CLIP, Administrative Call forwarding etc.

Switchboard connection is permitted i.e.  DDI and ISDN Point to Point operation are available.

Only 2 simultaneous call are permitted on the line.

The distance can be further from the exchange than Highway, typically 5km instead of 3km.

ETSI call clearing codes for BRI and PRI (from TBR3/TBR4)

• 1 - Unallocated (unassigned) number.
• 2 - No route to specified transit network.
• 3 - No route to destination.
• 6 - Channel unacceptable.
• 7 - Call awarded and being delivered in an established channel.
• 16 - Normal call clearing.
• 17 - User busy.
• 18 - No user responding.
• 19 - No answer from user (user alerted).
• 21 - Call rejected.
• 22 - Number changed.
• 26 - Non-selected user clearing.
• 27 - Destination out of order.
• 28 - Invalid number format.
• 29 - Facility rejected.
• 30 - Response to status enquiry.
• 31 - Normal, unspecified.
• 34 - No circuit or channel available.
• 38 - Network out of order.
• 41 - Temporary failure.
• 42 - Switching equipment congestion.
• 43 - Access information discarded.
• 44 - Requested circuit or channel not available.
• 47 - Resources unavailable, unspecified.
• 49 - Quality of service unavailable.
• 50 - Requested facility not subscribed.
• 57 - Bearer capability not authorized.
• 58 - Bearer capability not presently available.
• 63 - Service or option not available or unspecified.
• 65 - Bearer capability not implemented.
• 66 - Channel types not implemented.
• 69 - Requested facility not implemented.
• 70 - Only restricted digital information bearer capability is available.
• 79 - Service or option not implemented or unspecified.
• 81 - Invalid call reference value.
• 82 - Identified channel does not exist.
• 83 - A suspended call exists, but this call identity does not.
• 84 - Call identity in use.
• 85 - No call suspended.
• 86 - Call having the requested call identity has been cleared.
• 88 - Incompatible destination
• 91 - Invalid transit network selection.
• 95 - Invalid message specified.
• 96 - Mandatory information element is missing.
• 97 - Message type non-existent or not implemented.
• 98 - Message not compatible with call state or message type non-existent or not implemented.
• 99 - Information element non-existent or not implemented.
• 100 - Invalid information elements contents.
• 101
• 102
• 111
• 127