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Understanding Your SIP Taxes

The wages of sin are death, but by the time taxes are taken out, it's just sort of a tired feeling.
-- Paula Poundstone

There are very few things in life that I truly hate. Yes, there is much that I very much dislike, but hate is such a strong word that I like to save it for something really offensive. For example, I greatly dislike cold days, but I don't hate them. I love to ice skate on outdoor rinks, so it would be foolish for me to hate the thing that makes that kind of skating possible. I also severely dislike getting pulled over for speeding, but I understand that I shouldn't be driving so fast. I can't really hate the highway patrol officer for doing his or her duty, can I?

However, there is one thing in life that I can say, without a doubt, I truly hate. I really, really, really hate doing my taxes.

Now, don't get me wrong; I have no problem with paying for the services my state, city, county, and country provide me. I understand that there is no free ride, and paying my fair share isn't what I hate. What drives me crazy is figuring out how to and filing my taxes. If there was a way to just get paid and have the exact amount of tax taken out at the time of payment, I would be extremely happy.

So, what does this have to do with unified communications? Surprisingly, a lot. No, TurboTax hasn't added a section for SIP deductions, but it's not uncommon for vendors of SIP gear to sneak taxes into their products that may catch you off guard.

Let me start with session border controllers (SBCs). You should all know that an SBC sits on the network edge and performs tasks such as deep packet inspection, transcoding, encryption, decryption, remote user registration, and media forking. However, were you aware that some vendors provide all that functionality as part of the base package while others charge for bits and pieces? Well, you had better know that before you go shopping for an SBC and fall in love with the first one you see. You need to be clear about what you want your SBC to do in order to get accurate, up-front pricing. Switching NIC cards from copper to fiber after your purchase can add thousands of unplanned-for dollars, for example.

Next, there are the endpoints. You expect to pay for a physical SIP phone, but what you pay for a soft client can vary wildly from vendor to vendor. Some products, like Avaya's Communicator iOS, can be downloaded free of charge from the Apple App Store or Google Play Store. However, you still require a base license in order to register that free phone with the Aura system. Other downloadable soft clients might also start out free, but you end up paying for functionality not included out of the box. A common surcharge is encryption (TSL for SIP signaling and SRTP for media). Also, most will give you G.711 for free, but charge extra for licensed codecs such as G.729.

DSP (Digital Signal Processing) engineering comes into play when you convert from IP to TDM. I have worked with a number of customers who were forced to add additional gateways as part of their SIP upgrade in order to beef up their DSP count. Not having enough DSPs will lead to dead air, one way audio, and failed calls.

The next place to look would be SIP licenses. Again, some vendors give them away for free or as entitlements for other things you've purchased. Avaya does this. However, other vendors do not offer entitlements which can add significant cost to your overall purchase.

Don't be afraid to ask your SIP carrier similar questions: Do they charge separately for REFER? How do they bill for SIP bursting? Are there other "hidden" charges that only come out when you read through the fine print?

Lastly, ask how your vendor counts sessions in a SIP call. How many sessions does a simple point-to-point call consume? How many sessions does a conference call consume? What charges apply if a call is forked to a recording server like a Verint or Calabrio system?

It's important to be aware of what you want and how your vendors (there is always more than one throat to choke) charge for it. Like taxes, careful planning will help you avoid the sticker shock that guys like me always seem to experience in March and April.

Oh, I also hate vinegar flavored potato chips. How on earth can anyone eat those nasty buggers?

Andrew Prokop writes about all things unified communications on his popular blog, SIP Adventures.

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