Tag Archives: SIP VoIP

Demystifying SIP


The telecom industry has a tendency to shoot itself in the foot. It seems that every time a revolutionary idea emerges, it’s given a technoid sort of name that confuses the general public. SIP is no different.

Everyone knows what an apple is. Not everyone knows that the apple belongs to the subfamily Maloideae of the family Rosaceae. Why? Because no one cares…there’s no practical reason or value in knowing. And besides, who remembers this scientific jargon?

Likewise, everyone knows what a phone call is. Most everyone now knows what the Internet is. Very few people know what SIP is. The fact is the telecom industry, once again, labeled a revolutionary Internet communications capability – SIP – an acronym (no shortage in the industry on these) that describes its technical function, not unlike T-1, MPLS, DTMF, SMDS…the list goes on forever. And once again, the telecom industry has managed to intimidate and confuse the very people who need what it has to offer!

So let’s demystify this SIP thing once and for all. SIP stands for session initiation protocol (bare with me…it gets easier), a signaling protocol used for controlling multimedia over the Internet. More recently it has become associated mostly with the protocol for Internet phone calling that we know as VoIP. SIP enables VoIP calls to be made by most new business phone systems that are connected to the Internet with a high speed facility – DSL, fiber optics, wireless, etc.  A “SIP trunk” refers to the call path from a business phone system over a broadband connection and through the Internet – an alternative way of providing phone calling rather than the standard landline. If a phone system is not SIP-enabled, phone calling is still made possible by placing a protocol converter between the phone system and the Internet connection.

One more thing – why use SIP? There a few major reasons:

  • Cost reduction – The savings over traditional phone lines can be huge!
  • Scalability – Easy to implement, program and use.
  • Universality – It speaks the language of the global Internet.
  • Receptivity – The future of communications will be SIP-driven.

SIP – It’s that simple…well, almost. There are more technical aspects to SIP, but these are the basics. But the fact remains – the concept should have been given a different, more creative name by the telecom industry that everyone understands. Telecom should probably emulate the creativity of, let’s say, the computer industry. After all,  everyone knows what an apple is, thanks to Steve Jobs.