Spam Filter


The Skyetel Spam Calls Prevention service is a mechanism that blocks robocalls and solicitors from hitting your PBX by re-routing them to a pre-recorded message.


How Spam Prevention Works

One of the signature features of a spam caller is they place tens of thousands of calls per day to numbers that are geographically distributed throughout the country. Additionally, they tend to have very low average call length because people quickly realize it is a spam call and then hangup the call. This, and a few other top secret techniques, allows the Spam Prevention service to track telephone numbers that are frequently used for spam calls. In turn, that data gets turned into a database that Skyetel can query on every inbound call. 

It is important to note that Skyetel does not own this database - we only contribute to it (we also have to pay to access this data). This is actually one of the best features of this Database - many many carriers contribute to this database every day (Publicly traded carriers such as Comcast, Frontier, AT&T etc also contribute to and pay for this database). Because so many carriers contribute to this database, the results are extremely accurate and can effectively identify about 90% of spam calls. 

Calling your own phone numbers from our network may trigger the spam filter. For example, if 13609865200 calls 13609865200, we will assume that that call is fraudulent and it could be filtered. 

Enable Spam Prevention

To enable Spam Prevention, simply navigate to the phone numbers menu in the Skyetel Portal:


Select the number you would like to enable Spam Prevention on, and Configure "Spam Call Filter" from the Features menu:


Spam Risk Threshold


The Spam Risk Threshold is a numerical value that represents the likelihood that the party calling your phone number is spam. There is a lot of black magic that goes into generating this number, but the end result is the following:

0 – 39 = Low risk
40 – 79 = Medium risk
80 – 100 = High risk

You can adjust this metric to your preference in order to adequately adjust the volume of spam calls you recieve. By default, we use 80. 

What The Spam Filter Options Mean

Block Spam Calls

This is our default option. In this configuration, calls are sent to a recording telling them their calls have been rejected. You will see these calls in your CDRs on Skyetel, but they will not reach your endpoint.

Please note the Whitelist\Blacklist function only applies to DIDs you have configured with Block Spam Calls as the Spam Call Filter.

Pass through spam calls with SIP header

For our customers who want to maintain their own database for Spam Calls (and allow for custom whitelists) you can use this option. When enabled, we will route your calls to your endpoint whether or not they are spam. However, you will see a new SIP Header:


You will only have the following results:

P-Spam-Score: 0
P-Spam-Score: 1

If the result is 0, then the Risk Score did not exceed your specified threshold. If the result is 1, then the Risk Score did exceed your threshold.

In addition to the Spam Score, you will also receive the Spam Risk Score:


You may use this to configure your own custom routing. 

Do Not Cache This

Do not cache the Spam Risk Score - The Risk Score and the Spam Score change frequently (Often daily) and caching these results will cause you to maintain an outdated database and inadvertently block regular callers. 

Pass through spam calls with CID Prefix

With this option enabled, we will prepend "SPAM: " to the Caller ID of this call. This will allow you to answer spam calls, but warn your users before they answer. For this option to work, you must have our Caller ID settings enabled. 

Spamblock Bot

By enabling this feature, you are sending Spam calls to a Skyetel Lenny server. You can read all about Lenny here - but the TL:DR is that Lenny is a robot that keeps spam callers on the phone intentionally in order to torture them make it less economically feasible to keep robocalling.

We record all of our Spamblock Bot calls and put them in the call recordings section for your listening pleasure. Additionally, when Spamblock Bot is enabled, you can set an email address that you would like to receive the recordings at. This is great for hobbyists and home users who enjoy a little bit of humor (smile).

Please note - since we are recording Lenny calls, you will be billed for the cost of the recording like a regular recorded call.

Whitelist/Blacklist Callers


Please note this function only applies to DIDs you have configured with Block Spam Calls as the Spam Call Filter.

In order to Whitelist/Blacklist callers, you need to find the Call Record in our portal. Once you found it, you can either specify a number as "Spam" or "Not Spam." 

Spam = Mark this caller as a spam caller for all future inbound calls
Not Spam = Whitelist this caller as not a spam caller for all future inbound calls

Results are submitted and applied instantly, and should be effective within a few seconds. However, we may delay updating the record for up to 24 hours if we are undergoing maintenance or doing back-end updates.

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