Protection From Mailbox Owner Abuse

The corporate telecommunications manager must control use and potential abuse of corporate resources to provide the best service while controlling costs and maintaining security. Likewise, the revenue of a service bureau is dependent on being able to bill mailbox owners for use of the server. The NuPoint UM server allows you to place controls and limits in the server to ensure that mailbox owners use the server appropriately.

Line Groups

Service bureaus can provide mailbox owners with certain line groups for receiving messages, while having them pick up their messages on other line groups, either to control costs or to control call flow. To enforce this type of usage, you can use feature bits 101-109 to deny login on specific line groups; callers can leave messages, but are not able to log into a mailbox. In this way, you can also restrict access to certain information to internal ports only, or to “800” number ports where the server owner must pay for connect time.

Mailbox Usage

Depending on the number of phone lines or the storage hours available on your server, or on the levels of service that mailbox owners pay for, you can set LCOS parameters to control certain aspects of mailbox usage, such as connect time, number of messages stored, or storage duration.

If the number of phone lines to your server is limited, you can limit call duration by setting the Maximum login time parameter in each LCOS to a few minutes. On the other hand, if disk storage is a limiting factor, you can lower both the Caller message length and User message length, and set the Message count limit to a number that is equitable to all users assigned to each LCOS.

The amount of storage used on your server is the result of the number of messages stored and the length of storage time. You can control the storage times for played and unplayed messages by setting the two LCOS parameters: Played message retention and Unplayed message retention.

Besides setting limits on server usage, you must ensure that your mailbox listings are currentremove mailboxes that are no longer being used. Once you have removed a mailbox, the server automatically removes it from the Dial-by-Name database and from all distribution lists.

Messaging

Messaging between mailbox owners is the primary purpose of many voice mail systems, but you must use GCOS and FCOS settings to enforce restrictions on which mailboxes can exchange messages.

The primary tool for controlling messaging between mailboxes is the GCOS. Correct GCOS settings can effectively partition a server so that separate user groups are not aware of one another, or so that certain mailboxes can only receive or send messages to other specific mailboxes, such as in dispatcher situations.

GCOS structures also create partitioned Dial-by-Name. A mailbox owner cannot use Dial-by-Name to address a message to a mailbox that is not accessible due to GCOS restrictions; the server does not match or play inaccessible mailbox names.

You can also use FCOS settings to control the sources and destinations for messages. Feature bits 040 through 045 control a mailbox’s ability to receive messages from various sources, such as other users, outside callers, or distribution lists.  Feature bits 020 through 035 control the ability to make or give messages to users and distribution lists.

Outdials

Depending on the optional features purchased with your server, mailbox owners can send a variety of outdial calls, including call placement, message delivery, auto wakeup, and paging. To prevent abuse and to provide better call traffic, you can restrict different outgoing call types to specific line groups and set appropriate restrictions and limits on each line group. This prevents users from accessing other services on dedicated line groups and allows you to monitor resource usage.

Mailbox owners can use the message delivery feature for message waiting, in which the server calls a specified number when the mailbox owner receives a new message. The person who answers the phone must enter the correct passcode to access the mailbox, thus ensuring that only the mailbox owner can listen to the message.

Mailbox owners can use call placement to record a message and send it to a telephone number (as opposed to a mailbox). The message sender can record the name of the intended recipient and can optionally require a passcode before the message is played.

The FCOS and LCOS settings provide a tool for the administrator to control access to outdial services. Various feature bits enable use of the different features, and LCOS limits control the number of digits that a mailbox owner can enter for a target telephone number. You can set the message delivery, paging, and message phone lengths to seven digits to limit calls to the local service area, or 10 (or 11) digits to allow for long distance calls.