What is call filtering — by the Rabbinical Committee list and a personal block list

What is call filtering

Call filtering is a check made before a call goes through: the system looks at the number, compares it to a list, and decides whether the call continues as usual or not. The check happens on every call, automatically, without the person answering or the person dialing having to do anything.

The difference between filtering and ordinary blocking is mainly one of scope. Ordinary blocking is usually a decision about one number that someone entered by hand. Filtering is a service that works on all calls, against whole lists, and keeps working even as the lists change. You can read about blocking a single number in the article on Caller Blocking.

Filtering works in both directions. On an incoming call, it checks who is calling. On an outgoing call, it checks what number is being dialed. This way filtering protects not only the person answering, but also the person dialing.

When filtering is done in the PBX, and not on each phone separately, it applies to every device: a desk phone, an app on a cell phone or computer, and an extension that rings on a cell phone. They all go through the same check, as long as the call passes through the PBX.

Why filter calls

In the Haredi community, many people make sure that the phone, too, follows the guidance of the rabbis. At home, in an institution and in a business, the phone is a work tool, but it is also an opening: callers, messages and content come in through it, and through it you can reach any number. Call filtering keeps this opening within the limits the organization has set for itself.

There is also a practical side. An institution with many staff members, or a yeshiva with lines for its students, can't check every call on its own. The decision about what is allowed is made once, and the system carries it out on every call, at any hour.

Ordinary businesses have reasons too: sales call centers that call again and again, recorded messages, and callers who harass employees. These are all reasons to filter, even apart from the question of content.

Two lists: the Rabbinical Committee list and the personal block list

In Kesher's filtering service, every call is checked against two lists, and each one meets a different need.

The Committee's list is the shared base. Everyone who joined the service is filtered against it, without having to know which numbers are on it and without updating it themselves.

The personal block list is each customer's addition: numbers they want to block for themselves, for their own reasons. It lets them block more numbers, beyond the shared list.

The Rabbinical Committee list

The Rabbinical Committee manages a list of numbers. The decision about which numbers are on the list belongs to the Committee. The filtering service does not decide what is on the list. It checks every call against it and carries out what was decided.

For the customer, this means something simple: no need to build a list from scratch, no need to keep track of new numbers, and no need to decide alone about every number. Anyone who joined the service is filtered against the Committee's list, and every change the Committee makes to the list applies to all subscribers.

The check works in both directions. When someone calls you, the service checks the caller's number. When someone on your side dials out, the service checks the number they are dialing. A number the Committee blocked does not continue as usual, no matter who started the call.

The personal block list: numbers you block

Beyond the shared list, each customer has a list of their own. On it, they block numbers that matter to them, even if those numbers are not on the Committee's list.

A few examples of what goes on a personal block list:

• A sales call center that calls again and again, even after being asked to stop.
• A recorded-message number that reaches all the extensions one after another.
• A nuisance caller who has already been told there is nothing you can do for them.

You manage the personal block list yourselves: add a number when needed, and delete it when there is no longer a reason to block it.

It is worth keeping it in order. A list that grows without order sometimes also blocks people who no longer need to be blocked, for example a new supplier who got a number that once belonged to a sales call center. So it is good to know why each number is on the list, and to go over it from time to time. The article on Caller Blocking lists good habits for managing a list like this.

Incoming and outgoing calls: what is checked in each direction

Every call has two numbers: the caller's and the receiver's. The service always checks the number on the other side: on an incoming call, the caller's number; on an outgoing call, the number being dialed.

On an incoming call, the check relies on caller ID, the number that comes with the call. On an outgoing call, it relies on the number the person dialed. In both cases, if the number is on the Committee's list, the call does not continue as usual.

There is a small difference worth knowing here. On an outgoing call, the number is always known, because the person dialing entered it. On an incoming call, some callers hide their number. How to handle calls from a hidden number is a separate question, and the article on Caller Blocking explains the options.

What happens to a blocked call

"Blocking" doesn't have to mean hanging up. In Kesher's filtering service, a call with a number the Committee blocked is sent to a destination set in advance for that customer, such as a recorded message or another number, instead of continuing as usual.

The destination is set in advance, so the behavior is predictable: there is no need to decide again on every call, and every blocked call goes the same way.

A few things to think about when you set the destination:

• A short, respectful message. Sometimes the person who reaches the message simply dialed the wrong number. One clear sentence is better than a long explanation.
• On an outgoing call, the person who dialed hears the message. It should make clear that the call was blocked on purpose, so they don't think the line has a problem and try again and again.
• Another number is a good fit when you want someone responsible to know about the case, for example someone who can check whether there was a real need.

Where filtering happens: on the phone, at the phone company or in the PBX

There are several places where calls can be filtered, and the difference between them matters:

• On the phone itself. Some phones filter inside the device. This protects only that device. In an organization with many extensions, you have to take care of each device separately, and a new device starts from scratch.
• At the phone company. The filtering applies to your line with that company, based on what it offers.
• In the PBX. The filtering applies to every call that passes through a filtered point in the PBX, from any device: a desk phone, an app, or an extension that rings on a cell phone. A new device that connects to a filtered extension is filtered from the first moment, with nothing to set up on it.

Kesher's filtering service works in the PBX. It follows the calls of those who joined, while the calls are in progress, and checks them there. That's why it does not depend on the type of device.

One thing to keep in mind: the filtering applies to calls that pass through the PBX. A call that goes outside it, for example from a private cell phone that dials directly through the cellular carrier, does not go through this check.

What to filter: an extension, a number, a code or the whole system

Not every organization needs to filter everything. In Kesher's filtering service, you choose what is filtered:

• Extension: the calls of a specific extension, for example an employee's extension or a room's extension.
• Number: the calls that pass through a specific phone number of the organization.
• Code: the calls that pass through a specific routing code.
• The whole system: all the calls of the account.

The service identifies the point you chose and filters only the calls that pass through it. Other calls in the system continue as usual.

How do you decide? A yeshiva that wants all its lines to follow the same rule will add the whole system. An institution that wants to filter only the extensions in its rooms will add only those. An organization with a separate number for public inquiries may want to filter only that number.

The choice also affects the price: you pay by the number of lines filtered, and each extension, number or code you add counts as a line.

Before you start: five planning questions

Filtering works better when you decide in advance how it will fit into your work. Five questions worth answering before you join:

1. Which lines need filtering? The whole system, or only part of it. Go over the list of extensions, numbers and codes, and decide on each one.
2. Who is responsible for the personal block list? One or two people is best. When everyone adds numbers on a hunch, people who shouldn't be blocked get blocked too.
3. What will someone who is blocked get? A short, clear message, or the number of someone responsible. Write the message in advance.
4. What will happen when an employee runs into a block? Make sure they know it isn't a malfunction, and whom to ask if they have a question.
5. Who will add the lines? The account administrator can add the whole system. Another user can add only what they have permission to edit, so check in advance who will do it.

A few minutes of planning save a lot of questions later. These decisions also help you explain to your staff what has changed.

How to tell your staff

When filtering starts working, everyone who uses the phones should know. A short note to the staff prevents confusion:

• From what day filtering is active, and on which lines.
• What happens when you dial a blocked number: the call does not connect to it, but goes to a preset destination, such as a message. This is not a malfunction.
• Whom to contact with a question, or with a request to add a number to the personal block list.

In an institution with many staff members, you can post the note next to the phones, or send it as a short text message. People who know what to expect don't think the line is broken when they hear the message.

An example from the field

At the "Ohr HaChaim" Talmud Torah (a made-up name) there is an office, a teachers' room and extensions in the classrooms. The principal, Rabbi Menachem, wanted all of the institution's lines to follow the Committee's guidelines.

Yossi, the institution's system administrator, added the whole system to the service. From that moment, every incoming and outgoing call of the institution is checked against the Committee's list. When a number from the list calls, the call reaches the preset message, not the office.

After a few weeks, a sales call center started calling every morning, always from the same number. The number wasn't on the Committee's list, but the office didn't want to hear from it anymore. Yossi added it to the institution's personal block list, and those calls were blocked.

Once, when a teacher tried to call a number the Committee blocked from the teachers' room, he heard a message instead of a ring. The message, which the institution had written in advance, made it clear that the call was blocked on purpose, and he understood there was no problem with the line.

What filtering does not do

It is good to know the limits too, so you rely on filtering in the right places:

• List-based filtering checks numbers. The decision is made by the number on the other side, not by what is said on the call. A number that is not on the lists continues as usual.
• It applies only to what you added. A call that doesn't pass through any point you added is not filtered. If you want all lines filtered, add the whole system.
• It applies only to calls that pass through the PBX. A phone that dials another way does not go through the check.
• A displayed number is not always real. Some callers display a number that isn't theirs. You can read about this in the article on caller ID.

For calls that come from a different number each time, like most spam calls, the service also includes spam filtering, which identifies them by their behavior and not by a fixed list.

"Screening before connecting": a similar name, a different thing

In the settings of a number and of an extension in the PBX, there is a setting called "Screening before connecting". Despite the similar name, it is something else. There, the PBX plays the caller's number to the person answering, or asks the caller to record their name, before the call connects. This way the person answering knows who is on the line before the call is connected.

This is commonly known as Call Screening. It is a handy tool for anyone who wants to know who is calling before talking to them, but it does not check the number against a list, and it does not block anything on its own. The filtering service, on the other hand, checks every call against lists, and a call with a blocked number does not continue as usual.