H.323 vs. SIP

Discussion related to the ITU-T Recommendation H.323
matwenty8
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H.323 vs. SIP

Post by matwenty8 »

I just reviewed the website page comparing the H.323 and the SIP protocols:

http://www.packetizer.com/voip/h323_vs_sip/

Does anyone know if this information is still up to date? If not, which information should be updated?

Thanks,

Matt
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paulej
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Re: H.323 vs. SIP

Post by paulej »

We try to keep it up-to-date, but if there are any sections you believe are inaccurate or need clarity, then definitely point it out to us.
vipeenexy
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Re: H.323 vs. SIP

Post by vipeenexy »

What is the meaning of multimedia of computing? I'm Degree Student in one of Malaysia University. I'm taking Bachelor of Multimedia for computing. but I can not understand what I'm learning now. first time I saw the Major, I thought I'm going to study about graphic design, animations or something related to design. Already pass about 1 year, mostly my subjects are business and web developer only. for animation tool, I only know about Flash and Director. I thinks I took wrong major.
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paulej
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Re: H.323 vs. SIP

Post by paulej »

vipeenexy,

Not sure. Perhaps if you detailed some of the course requirements it might help. Since you did not say "multimedia communications" then I would guess what you might be studying is multimedia like computer graphics, animation, etc. Alas, it is very hard to say what you would be learning just from the title.

Paul
whshockey2000
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Re: H.323 vs. SIP

Post by whshockey2000 »

On the topic of H.323 vs SIP...after reviewing the site I have a couple of questions. I will be presenting benfits for video conferencing through SIP as well as how our company would benefit by migration from H.323 to SIP. It seems that after reading Packetizers "H.323 vs. SIP" article that this would be counter intuitive. Any suggestions?
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paulej
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Re: H.323 vs. SIP

Post by paulej »

whshockey2000 wrote:On the topic of H.323 vs SIP...after reviewing the site I have a couple of questions. I will be presenting benfits for video conferencing through SIP as well as how our company would benefit by migration from H.323 to SIP. It seems that after reading Packetizers "H.323 vs. SIP" article that this would be counter intuitive. Any suggestions?
The comparison document was created to show the differences between the protocols, but it does not go into a level of detail that addresses any specific requirements one might have in an environment.

If your primary use is for videoconferencing, H.323 presently has more capabilities than SIP. The IETF is aggressively working on that, but it is a few years behind. (It has taken the IETF more than 15 years to try to get parity in some video capabilities with H.323.) If your primary use is voice, either H.323 or SIP would work and there is a trend with service providers today to offer SIP "trunks". (Personally, I find the term "SIP trunk" funny, since it goes against the whole idea of SIP in the first place of not being a "telco" type of protocol. But, that's another matter...)

Some have sighted SIP as being advantageous because most devices use UDP. This allows one to develop complex architectures that have multiple signaling hops and "minimize" the cost. I'm thinking about IMS here. The challenge with this logic is that building complex architectures are usually unnecessary. Some of the world's largest H.323 networks included a hierarchy of Gatekeepers that resolve addresses, but signaling always goes directly point-to-point within the core network. Thus, they are often more scalable at a lower cost.

In any case, the document was not intended to suggest what the best choice is for all environments. The selection of protocol depends on requirements. I have a preference for H.323 for video. I also have a preference for H.323 for NAT/FW traversal, since there are working products that I can get a little to no cost. However, service providers like Vonage prefer SIP have a proprietary means of getting through NAT/FW devices.
jimm1909
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Re: H.323 vs. SIP

Post by jimm1909 »

paulej wrote: If your primary use is voice, either H.323 or SIP would work and there is a trend with service providers today to offer SIP "trunks". (Personally, I find the term "SIP trunk" funny, since it goes against the whole idea of SIP in the first place of not being a "telco" type of protocol. But, that's another matter...)
I'm glad someone agrees with me on the "SIP trunk" terminology matter. I've always thought it was counter intuitive to the idea of SIP as well. Been saying it for years.

-Jim
Last edited by jimm1909 on Wed Feb 25, 2015 4:00 pm, edited 1 time in total.
jimm1909
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Re: H.323 vs. SIP

Post by jimm1909 »

whshockey2000 wrote:On the topic of H.323 vs SIP...after reviewing the site I have a couple of questions. I will be presenting benfits for video conferencing through SIP as well as how our company would benefit by migration from H.323 to SIP. It seems that after reading Packetizers "H.323 vs. SIP" article that this would be counter intuitive. Any suggestions?
By the way, I'd be interested to hear if anyone else has any more suggestions.

Thanks in advance,

-Jim
Last edited by jimm1909 on Sat Feb 14, 2015 1:47 am, edited 1 time in total.
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paulej
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Re: H.323 vs. SIP

Post by paulej »

Jim,

I think the answer to the question is actually fairly simple: because that is what the major service providers are offering. Given the rise in mobile phones, that's where carriers are looking to make the bulk of their revenue. They are also of the mind that people using those mobile phones will use their phone services. That's a logical assumption, but what protocols do they implement? That's where 3GPP comes in. They decided back in 1999 to adopt SIP as the protocol of choice on mobile networks. As a part of that work, they created IMS, which is a SIP network that sits in the service provider cloud. It's complex has heck and may or may not offer any better quality than Skype over 4G :) Certainly, IMS is not better at providing voice over 3G than the GSM protocols of old.

Nonetheless, carriers have adopted SIP for mobile. They're also adopting SIP on the land-line side, as that only makes sense. Some have even tried pushing the complex IMS stuff into the enterprise. I'm not convinced that's a good idea, but that's a debate for another day.

And so, the mere fact that SIP is what carriers are predominantly offering these days is probably the single biggest reason to use SIP for trunk connections between the enterprise and the rest of the world. It doesn't really matter that SIP is fairly weak in terms of many features. Service providers do not offer a rich set of features, anyway.

For enterprise video conferencing equipment that connects only to other enterprise video conferencing equipment (either over a LAN or WAN), then H.323 is a good choice. In that case, the protocol really does not matter (as far as the service provider is concerned) and H.323 provides a richer set of video capabilities.
john sam
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Re: H.323 vs. SIP

Post by john sam »

H.323 and the SIP (Session Initiation Protocol) are protocol standards of IP telephones. The current version of H.323 is version 4 [1]. SIP is an older protocol when compared to H.323. H.323 is more robust and inter-operable when compared to SIP.
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