For years businesses have utilized PRI for their voice communication.  Now SIP is becoming a more popular and PRI is being phased out.  Here’s a line by line comparison of the two technologies:

  • sip vs priPRI stands for Primary Rate Interface.
  • SIP stands for Session Initiation Protocol.
  • PRI is part of the Public Switched Telephone Network.
  • SIP is Voice over Internet Protocol (VoIP).
  • PRI’s are sold per circuit.  Each circuit provides 23 channels or call paths.
  • SIP is sold per channel.
  • PRI is completely separate from a company’s internet or data circuits.
  • SIP is typically sold with internet access, on a data circuit or as a part of a data network, like MPLS.
  • PRI offer DID functionality.
  • SIP works with DIDs and out of area DIDs, so a company is not limited to the phone numbers in its geographical area.  SIP DIDs can be rerouted, in the event of a natural disaster
  • PRI channels are static; they sit dormant when they’re not in use.
  • SIP is dynamic.  When SIP trunks aren’t in use, the bandwidth they utilize is freed up for data and other transmission.
  • Multiple users at a given or networked location can share the voice channels provided by a PRI.  If the number of call channels is inadequate, an entire new circuit would be necessary, which could take weeks to implement.
  • Users, companywide, can share SIP trunks centralized at a company’s host site.  If the number of SIP trunks is inadequate, new trunks can be established in a few days.
  • PRI requires a local loop, provided by the incumbent provider.  Phone service providers need an agreement with an incumbent to offer PRI, so PRI service has a more limited availability than SIP.
  • SIP is offered by just about every phone service provider in the telecom industry.
  • PRI requires the existence of a T1 card in a PBX or phone system.
  • SIP requires a SIP gateway to connect to the public switched telephone network but can be engineered to work with any type of phone system.
To receive more information on SIP or PRI, or consultation on converting from PRI to SIP, call CarrierBid today or complete the form on the bottom of the page.

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