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Overcoming SIP Phobia

In general, I am a fairly calm, rational, and understanding person. I am patient in difficult situations and refrain from overreacting when things don't go my way.

However, I struggle with stupidity and laziness -- big time! And I don't necessarily mean my own (both of which I have been known to indulge in every now and then). I struggle when I am forced to deal with a situation that I know hasn't been thought out, and also with people who are unwilling to recognize their ridiculousness.

Case in point is a recent project that required my so-called expertise. My coworker and friend, Elaine, is working with a company looking to bring in SIP trunks from a major carrier (who shall remain unnamed). From my vantage point, this is a fairly straightforward task, and one I've seen successfully repeated across the country many times. In the case of this company, they were already using SIP trunks from a smaller carrier and felt that this new project would be a slam dunk. Unfortunately, the new carrier had other ideas and wasn't ready to suit up as quickly as any of us had expected.

We presented the requirements and configuration to the carrier (number of trunks, codecs, on-premises session border controllers (SBCs), etc.) and asked for a quote. Instead, we received a multipage document with questions so involved that even I, the self-proclaimed SIP guru, was baffled.

It began easy enough:

  • What are the makes and models of the hard and soft phones you are using?

  • Do you support SIP over UDP?

  • Do you support RFC 2833 for sending DTMF?

Motherhood and apple pie questions that I can answer in my sleep!

Unfortunately, those were just the teasers, and the questions quickly turned quite nit-picky to the point of nastiness:

  • If the IP PBX receives a 422 (Session Interval Too Small) response message in response to an INVITE request, then the IP PBX shall retry the INVITE request. The MIN-SE value in the new INVITE shall be set to the largest MIN-SE value in the 422 response. Is this standard supported?

  • For simultaneous and sequential ring scenarios, once you return an OK with SDP, can you accept a re-Invite with no SDP, respond with an OK with session attribute "sendrcv" and then accept an ACK with SDP with session attribute "sendrcv"?

  • Can your IP PBX support the "Intra-Site Transfer" function using re-INVITE as specified in SIP Specification Document?

Huh?

I will spare you the additional 12 pages of questions, but I hope you see my frustration. These are not the kind of things that most customers or their business partners should ever be expected to answer. Still, this carrier insisted that each and every one be answered before it would talk with us.

And this, my friends, is one of the reasons why SIP hasn't been as fully adopted as I would like it to be – legacy service providers that are still afraid of that big, bad, scary IP telephony.

A few weeks ago, I wrote an article here on No Jitter that I called, The Trouble with Standards is That They Rarely Are. In it, I addressed the fact that manufacturers and service providers have taken liberties with SIP, and one vendor's interpretation may not be the same as another's. I also stated that there are tools and methodologies to fix that.

SBCs, session management servers, and even SIP-aware applications can recognize differences and adapt between one version of SIP and another version of SIP. This allows your Avaya system to talk to Cisco to talk to Verizon to talk to Mitel. Adaptation can cure the misconceptions, misunderstandings, and downright proprietary aspects of SIP.

And yet, this major carrier insisted that these questions be answered before the project could proceed. Is its SIP infrastructure that inflexible? Does it lack all confidence in its product offering?

Carriers Can Adapt, Too
Now, I am not against questions, but these are the wrong questions. If it were me, the questionnaire would look similar to the following:

  • What codecs do you require?

  • What is the maximum number of active sessions?

  • What SBC will you be using?

  • What is the make, model, and version number of your IP PBX?

Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

Follow Andrew Prokop on Twitter and LinkedIn!
@ajprokop
Andrew Prokop on LinkedIn

  • Do you support SIP over UDP?

  • Do you support RFC 2833 for sending DTMF? Motherhood and apple pie questions that I can answer in my sleep!

    Unfortunately, those were just the teasers, and the questions quickly turned quite nit-picky to the point of nastiness:

    • If the IP PBX receives a 422 (Session Interval Too Small) response message in response to an INVITE request, then the IP PBX shall retry the INVITE request. The MIN-SE value in the new INVITE shall be set to the largest MIN-SE value in the 422 response. Is this standard supported?

    • For simultaneous and sequential ring scenarios, once you return an OK with SDP, can you accept a re-Invite with no SDP, respond with an OK with session attribute "sendrcv" and then accept an ACK with SDP with session attribute "sendrcv"?

    • Can your IP PBX support the "Intra-Site Transfer" function using re-INVITE as specified in SIP Specification Document?

    Huh?

    I will spare you the additional 12 pages of questions, but I hope you see my frustration. These are not the kind of things that most customers or their business partners should ever be expected to answer. Still, this carrier insisted that each and every one be answered before it would talk with us.

    And this, my friends, is one of the reasons why SIP hasn't been as fully adopted as I would like it to be – legacy service providers that are still afraid of that big, bad, scary IP telephony.

    A few weeks ago, I wrote an article here on No Jitter that I called, The Trouble with Standards is That They Rarely Are. In it, I addressed the fact that manufacturers and service providers have taken liberties with SIP, and one vendor's interpretation may not be the same as another's. I also stated that there are tools and methodologies to fix that.

    SBCs, session management servers, and even SIP-aware applications can recognize differences and adapt between one version of SIP and another version of SIP. This allows your Avaya system to talk to Cisco to talk to Verizon to talk to Mitel. Adaptation can cure the misconceptions, misunderstandings, and downright proprietary aspects of SIP.

    And yet, this major carrier insisted that these questions be answered before the project could proceed. Is its SIP infrastructure that inflexible? Does it lack all confidence in its product offering?

    Carriers Can Adapt, Too
    Now, I am not against questions, but these are the wrong questions. If it were me, the questionnaire would look similar to the following:

    • What codecs do you require?

    • What is the maximum number of active sessions?

    • What SBC will you be using?

    • What is the make, model, and version number of your IP PBX?

    Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • Do you support RFC 2833 for sending DTMF? Motherhood and apple pie questions that I can answer in my sleep!

    Unfortunately, those were just the teasers, and the questions quickly turned quite nit-picky to the point of nastiness:

    • If the IP PBX receives a 422 (Session Interval Too Small) response message in response to an INVITE request, then the IP PBX shall retry the INVITE request. The MIN-SE value in the new INVITE shall be set to the largest MIN-SE value in the 422 response. Is this standard supported?

    • For simultaneous and sequential ring scenarios, once you return an OK with SDP, can you accept a re-Invite with no SDP, respond with an OK with session attribute "sendrcv" and then accept an ACK with SDP with session attribute "sendrcv"?

    • Can your IP PBX support the "Intra-Site Transfer" function using re-INVITE as specified in SIP Specification Document?

    Huh?

    I will spare you the additional 12 pages of questions, but I hope you see my frustration. These are not the kind of things that most customers or their business partners should ever be expected to answer. Still, this carrier insisted that each and every one be answered before it would talk with us.

    And this, my friends, is one of the reasons why SIP hasn't been as fully adopted as I would like it to be – legacy service providers that are still afraid of that big, bad, scary IP telephony.

    A few weeks ago, I wrote an article here on No Jitter that I called, The Trouble with Standards is That They Rarely Are. In it, I addressed the fact that manufacturers and service providers have taken liberties with SIP, and one vendor's interpretation may not be the same as another's. I also stated that there are tools and methodologies to fix that.

    SBCs, session management servers, and even SIP-aware applications can recognize differences and adapt between one version of SIP and another version of SIP. This allows your Avaya system to talk to Cisco to talk to Verizon to talk to Mitel. Adaptation can cure the misconceptions, misunderstandings, and downright proprietary aspects of SIP.

    And yet, this major carrier insisted that these questions be answered before the project could proceed. Is its SIP infrastructure that inflexible? Does it lack all confidence in its product offering?

    Carriers Can Adapt, Too
    Now, I am not against questions, but these are the wrong questions. If it were me, the questionnaire would look similar to the following:

    • What codecs do you require?

    • What is the maximum number of active sessions?

    • What SBC will you be using?

    • What is the make, model, and version number of your IP PBX?

    Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • For simultaneous and sequential ring scenarios, once you return an OK with SDP, can you accept a re-Invite with no SDP, respond with an OK with session attribute "sendrcv" and then accept an ACK with SDP with session attribute "sendrcv"?

  • Can your IP PBX support the "Intra-Site Transfer" function using re-INVITE as specified in SIP Specification Document? Huh?

    I will spare you the additional 12 pages of questions, but I hope you see my frustration. These are not the kind of things that most customers or their business partners should ever be expected to answer. Still, this carrier insisted that each and every one be answered before it would talk with us.

    And this, my friends, is one of the reasons why SIP hasn't been as fully adopted as I would like it to be – legacy service providers that are still afraid of that big, bad, scary IP telephony.

    A few weeks ago, I wrote an article here on No Jitter that I called, The Trouble with Standards is That They Rarely Are. In it, I addressed the fact that manufacturers and service providers have taken liberties with SIP, and one vendor's interpretation may not be the same as another's. I also stated that there are tools and methodologies to fix that.

    SBCs, session management servers, and even SIP-aware applications can recognize differences and adapt between one version of SIP and another version of SIP. This allows your Avaya system to talk to Cisco to talk to Verizon to talk to Mitel. Adaptation can cure the misconceptions, misunderstandings, and downright proprietary aspects of SIP.

    And yet, this major carrier insisted that these questions be answered before the project could proceed. Is its SIP infrastructure that inflexible? Does it lack all confidence in its product offering?

    Carriers Can Adapt, Too
    Now, I am not against questions, but these are the wrong questions. If it were me, the questionnaire would look similar to the following:

    • What codecs do you require?

    • What is the maximum number of active sessions?

    • What SBC will you be using?

    • What is the make, model, and version number of your IP PBX?

    Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • Can your IP PBX support the "Intra-Site Transfer" function using re-INVITE as specified in SIP Specification Document? Huh?

    I will spare you the additional 12 pages of questions, but I hope you see my frustration. These are not the kind of things that most customers or their business partners should ever be expected to answer. Still, this carrier insisted that each and every one be answered before it would talk with us.

    And this, my friends, is one of the reasons why SIP hasn't been as fully adopted as I would like it to be – legacy service providers that are still afraid of that big, bad, scary IP telephony.

    A few weeks ago, I wrote an article here on No Jitter that I called, The Trouble with Standards is That They Rarely Are. In it, I addressed the fact that manufacturers and service providers have taken liberties with SIP, and one vendor's interpretation may not be the same as another's. I also stated that there are tools and methodologies to fix that.

    SBCs, session management servers, and even SIP-aware applications can recognize differences and adapt between one version of SIP and another version of SIP. This allows your Avaya system to talk to Cisco to talk to Verizon to talk to Mitel. Adaptation can cure the misconceptions, misunderstandings, and downright proprietary aspects of SIP.

    And yet, this major carrier insisted that these questions be answered before the project could proceed. Is its SIP infrastructure that inflexible? Does it lack all confidence in its product offering?

    Carriers Can Adapt, Too
    Now, I am not against questions, but these are the wrong questions. If it were me, the questionnaire would look similar to the following:

    • What codecs do you require?

    • What is the maximum number of active sessions?

    • What SBC will you be using?

    • What is the make, model, and version number of your IP PBX?

    Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • What codecs do you require?

  • What is the maximum number of active sessions?

  • What SBC will you be using?

  • What is the make, model, and version number of your IP PBX? Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • What is the maximum number of active sessions?

  • What SBC will you be using?

  • What is the make, model, and version number of your IP PBX? Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • What SBC will you be using?

  • What is the make, model, and version number of your IP PBX? Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn

  • What is the make, model, and version number of your IP PBX? Short and simple, and in my mind, more than enough to give this project a thumbs up or a thumbs down. The first two are all about features and sizing, which should cover quite a bit of the cost aspect. The second two tell me what environment I will be faced with and what I may or may not need to do in order to adapt to it.

    Yes, Mr. Carrier, you also have an SBC on your end that can be configured for any sort of system it is facing. You can adapt, too.

    If you call something that was invented in the 1990s new, then SIP is new. That's not the way I see it, though. I call SIP battle tested and combat ready. I also call this carrier's way of thinking antiquated and counterproductive, and it's time it moved beyond fear and on to being confident enough to know that its product will work under all sorts of conditions.

    Ask your questions, but ask the right questions. Step out of your comfort zone of ISDN trunks and into the world of multimedia communications that can be made to work no matter with which system you are interfacing. That's the power of SIP and open standards. That's the power of a slam dunk.

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

    Follow Andrew Prokop on Twitter and LinkedIn!
    @ajprokop
    Andrew Prokop on LinkedIn