Multi Site Networking

When connecting IP Office systems together over IP or packet-based networks, Small Community Networks (SCNs) enhance feature transparency. These networks can support up to a maximum of 1000 users across 32 sites.

IP Office supports the following features in an SCN environment:

Basic call setup (voice)
Supported by H.323 and SIP on IP trunks
Call Hold (local)
Supported by H.323 and SIP on IP trunks
Call Transfer (local)
Supported by H.323 and SIP on IP trunks
Called/Calling Name
Supported by H.323 and SIP on IP trunks
Called/Calling Number
Supported by H.323 and SIP on IP trunks
Busy Lamp Field (BLF)
Call Back When Free
Location based time zones
Different times zones for group of extensions based on locations. For 96xx, 16xx, 11xx/12xx, D100, and E129 phones
Centralized Personal Directory
For 1400, 1600, 9600 and T3 phones and Avaya one-X® Portal for IP Office
Centralized System Directory
For 1400, 1600, 9600 and T3 phones and Avaya one-X® Portal for IP Office
Centralized Call Log
For 1400, 1600, 9600 and T3 phones and Avaya one-X® Portal for IP Office
Centralized Voicemail
Preferred Edition. Support for mailboxes, call recording, dial by name and auto attendants. Remote queuing on remote systems is also supported.
Distributed/Backup Voice Messaging
Internal Directory
Absence Text
Distributed Hunt Groups
Hunt groups can include users located on other IP Office systems within the network.
Remote Hot Desking

Users can hot desk between IP Office systems within the network. The system on which the user configured is termed their home IP Office; all other systems are remote IP Office systems.

Breakout Dialing
This feature allows the user to select an IP Office system in the network from a displayed list and then dial a subsequent number as if dialing locally on the chosen system. This feature is triggered either by a programmable button or short code.


As an example, in an SCN configuration of System A and System B where the centralized voicemail is connected to System B, and a number of IP phones are connected to either System A or System B. If System B fails then:

  • System A will automatically take over from System B and support IP phones, hunt groups, and DHCP if required.

  • Voicemail Pro will reregister to System A.

  • For users in an SCN, when they hot desk to another IP Office system, they retain their licensed profile setting as configured on their home system.

  • All System B users’ personal contacts and call logs will continue to be available (96×1, 9600, and 1600 phones).

For multisite networks, VCM modules are required in all systems being connected. The IP lines may be configured in a start or a meshed configuration. One of the advantages of a meshed configuration is that it removes the risk of a single point of failure within the network. Also the names and numbers (groups, line, services, etc.) on the separate IP Office systems should be unique to reduce potential maintenance confusion.

EachIP Office system broadcasts UDP messages on Port 50795. These broadcasts typically recur every 30 seconds but BLF updates are potentially more frequent. There are no updates if there is no activity and the overall level of traffic is very low – typically less than 1 kbps per system.

Multisite networking is supported between IP Office systems with differing software levels but network features will be based on the lowest level of software within the network. This option is intended to allow the phased upgrading of sites within a multisite network and it is still recommended that all systems within a network are upgraded to the same level where possible.

If larger networks are required Q.SIG can be used to link multiple SCNs together. Functionality between the communities is governed by the Q.SIG feature set.

Voice networking licenses

On IP500 V2 systems, multisite networking (with SCN) requires one or more additional licenses. Server Edition Expansion (V2) systems do not require voice networking licenses.

Q.SIG, H.323 and SCN capabilities are not enabled by default on IP500 V2. An additional license is required to enable this functionality with 4 simultaneous networking channels (no channel limit for Q.SIG). Additional channels can then be licensed in increments of 4. A Voice Networking license is still required to enable TDM Q.SIG, even though there is no limit to the number of TDM Q.SIG calls that can be made or received once licensed.

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