SIP Phone Service, Features & Benefits, Part 2

VoIP background concept

Greetings from the frozen tundra!

In my last post, I provided an introduction to SIP phone service.  I now want to share with you two reasons why businesses love SIP service.

The first, which should come as no surprise, is cost. SIP service is incredibly affordable.  Local SIP calling plans are typically in the $8-$12 range (per line, or channel), and those with unlimited long distance are usually between $25-$35 per month.  When you consider that traditional telephone lines weigh in at around $35 / month – just for local service – the cost savings is immediately apparent for an SMB that does a lot of long distance calling.

The second great feature of SIP is the ability to have Direct Inward Dial (DID) service, or in layman’s terms, external 10-digit telephone numbers.  To understand what makes DID’s so special, though, let’s step back for a moment and explore traditional analog phone service.  Businesses that use plain old telephone lines (POTS) often advertise just their main business telephone number (BTN), but then behind the scenes retain a certain number of roll-over lines to receive a 2nd, 3rd, or 4th concurrent call.  Technically speaking, each roll-over line is tethered to its own 10-digit telephone number, but most callers are only aware of the advertised BTN. That is, until the business makes an outbound call on line 5. . . . .  You see, when it comes to analog phone lines, the telephone company is legally required to send the Caller ID of the particular telephone number that is being called from. . . which can be very confusing to the person that receives the call. Especially if the rollover lines are not in some sequential order.

In the mid-1990’s a new technology called PRI was introduced to the telecom marketplace. This was basically a digital T1 circuit dedicated for voice calling, and it allowed 23 concurrent phone calls and a virtually unlimited number of very cheap DID’s (usually purchased in blocks of 20 numbers). So companies could retain their advertised BTN and have other telephone numbers assigned to their business too. These DID’s could be provided to each employee or department, so that external callers could reach them directly. This provided faster communication, freed up the receptionist to do othetasks (rather than answering everyone’s calls), and created the appearance of being a much larger enterprise to their callers.  But PRI’s were expensive when they first came into the market, and many SMB’s just didn’t need 23 lines, so DID service was not an viable option for them.

Here’s another cool fact about DID’s. Do you remember the small problem mentioned earlier, regarding analog phone lines and the confusing caller ID issue for any outbound call that wasn’t using the main line?  Well, with digital DID service, the phone system gained the flexibility to send out any phone number that it wants for Caller ID, regardless of the specific line that was used.  So every outbound call can present the company’s main telephone number, or the employee’s individual DID, or something completely different.

So, fast forward to today: DID is a standard feature in the SIP world. Which means that companies that only need 3, or 5, or even 12 SIP lines can utilize DID in their business. And to take it one step further, because SIP is an IP technology, and no longer bound by the old rules of telecom, businesses are now able to assign non-local phone numbers to their account.

But why would businesses want to have a non-local phone number, you might ask?  Well, I invite you to tune in to my next post. : )

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