Business Internet Phone Service Blog

Co-written by Larry Browne, member of the OnSIP support team, and Nicole Hayward, member of the OnSIP marketing team.

We get many calls and cases in the OnSIP support bunker about caller ID. The most common one is “Why isn’t my caller ID showing when I call my wife?”

Yeah, about that... got a few minutes? I won’t completely ruin your day with the long, technical (boring) explanation. Here's a quick explanation about the the history of caller ID and OnSIP's implementation of this feature.

The History of Caller ID

Caller ID started as, and still is, a vanity feature. "The first market trial for Caller ID and other "Custom Local Area Signaling Services" was conducted by BellSouth as one of the "TouchStar" services on July 7, 1984 in Orlando, Florida. The Lines of Business (marketing) department in BellSouth Services named the service 'Caller ID'" (Wikipedia)

Caller ID is actually two bits of information: the caller's number and the subscriber name associated with that caller's number. This information is transferred as so: When a call is made, the originating phone switch sends the caller's number. Then, with the caller's number, the callee's service provider is responsible for looking up the caller's subscriber name.

When it was developed, the world was primarily a realm of Plain Old Telephone Service (POTS) lines, and the caller information was tied to the Central Office switch to which the wires were connected. Since there were also relatively few carriers at the time, it was easy to keep track of the caller ID information in one place.

Caller ID Today

Enter wireless and VoIP phones, hundreds of local/long distance carriers, Baby Bell breakups, consolidations, mergers, and the like, and the map has gotten much more fragmented. Unlike phone numbers and DNS, wherein there are internationally recognized databases that are authoritative sources, there is no central authority or regulation for caller ID. There are no FCC guidelines regarding its accuracy by carriers. While there are federal regulations regarding telemarketers and spoofing, carriers can maintain their caller ID databases as they see fit.

We offer caller ID for our OnSIP customers, and we don’t charge extra for it. We offer this feature by querying a reputable Caller Name (CNAM) database.

How OnSIP's Caller ID Works

On an inbound call, the call is sent to us, often from the Public Switched Telephone Network (PSTN), with a 10 digit number sent from the caller's provider. We take that number and look it up in the CNAM database to which we subscribe, and if there is a name, we send it to the OnSIP callee's registered phone(s) for display. Usually, this is between 9-12 characters. If there is no information on file, then we will send a best approximation of the geographic area for the phone number (e.g. New York, NY).

Outbound caller ID works the same way: we send the number to the PSTN, and the callee's provider does the lookup against their database, which may not be the same as ours. If the callee's provider uses the same CNAM database as we do, then chances are the caller ID name you have set in your account or user record will accurately appear there.

We send all subscriber updates that OnSIP users make to our CNAM provider every night, and the changes can show up quickly - in as little as 24 hours. However, the information may take a while to propagate to other CNAM databases. So, if an OnSIP customer updates their Caller ID settings, the change will be quickly evident if s/he calls someone whose telephone service provider uses the same CNAM database. Unfortunately, if the callee's provider uses a different CNAM database, the change may not be evident for weeks.

When a call is made to a cell phone, most times the phone does a lookup against the contacts in the phone’s address book, and if the number isn’t there, will display Unknown. This varies across providers, so check the service level of the individual provider for exact information.

Final Note

This is the long and short of caller ID. Because the other providers use different CNAM databases, and some rarely or never update them, the information received on the termination end is sometime wrong. And since it’s a feature, and not a regulatory requirement, they rarely have the time or inclination to fix it.

The good news is that we use a top, reputable CNAM database, so the caller ID information passed to you is dependable. I hope this has been a brief and helpful overview of caller ID!

This blog is by Eric Phipps, NOC Technician

One of the long requested features we’ve had at Junction Networks has been the introduction of a parking server, which would allow us to place a call on hold and allow another phone to pick up that call. We will shortly begin rolling out this feature, but one of the questions we dealt with while developing the feature is: what’s the easiest way to let people know that they have that call? We think it’s intercoms and paging systems.

Exploring solutions
With that type of solution in mind, we set out to find the best intercom system that would work with OnSIP. We tested three companies who have a hand in shaping this field and here’s what we found.

The field for competition in this segment of VoIP isn’t that large. When consulting with suppliers, customers and others who work in the VoIP industry, we kept hearing the same three names - CyberData, Digital Acoustics and Valcom. Each of these were well regarded by the market, so we wanted to put them head to head to find out which of these would be the best for our users.

We had problems with both the Valcom and the Digital Acoustics devices, unfortunately. The issues don’t discount their value within the field of SIP paging, but just mark them as being incompatible with OnSIP at this time.

Testing Cyberdata's offerings
The two Cyberdata systems which we looked at both excelled with the OnSIP system. Once we got them up and running, they were good, stable devices with excellent build quality. They were very easy to use and very easy to set up.

We tested the SIP-enabled IP Ceiling Speaker v2.0 and the SIP-enabled IP Outdoor Intercom. The most difficult aspect was finding the IP address of the devices in order to log into their webpages to set them up. We plugged in the devices onto our network and then checked the DHCP lease against the manufacturer’s MAC address. From there, we logged into the device and manually set a static IP address; this way, we would always know the IP address of the device, making maintenance easier.

We also found that the Nightringer functioned as needed for both devices. Nightringer is an option where, if a call is sent to the device, the device will broadcast a ringtone to let somene know that there is a phone call. This is typically handy in a warehouse situation. A speaker can broadcast a ringing sound to alert a late night worker that there is an inbound call. Cyberdata accomplishes this by creating a secondary user agent within their devices which does not broadcast speech, but rather upon receipt of the call will broadcast the ringing sound. For our testing purposes, we created a group with the Nightringer user and a Bria softphone, and we were able to replicate the expected behavior.

In our survey of the market for various paging systems, we learned that the three lead manufacturers all offer a fairly solid product. However, software issues hampered both the DigitalAcoustics and Valcom lines, making Cyberdata the line we found to work best with OnSIP right out of the box. Cyberdata was the only device to make it to the Junction Networks compatibility guide.