What Is the Difference Between H.323 and SIP?

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Before understanding the difference between H.323
and SIP, there are a few things which need to be
put in perspective. Both of them are
communication protocols and both of them were
introduced around the same time and it must have
happened around two decades ago. However, there
certainly are some differences between the two
protocols as far as their scope is concerned.
This certainly widens the differences between the
two as far as some features and functions are
concerned.
What Is SIP?
SIP is the acronym for Session Initiation
Protocol and it is basically like any
application layer protocol. It is used for VoIP.
It also plays a big role in controlling
communication sessions where multimedia is used.
Apart from VoIP, there are other areas too where
SIP can be used. Hence when it comes to instant
messaging, online games, video conferencing,
file transfer or even fax over IP, SIP has a
varied and wide usage. Ever since it was
introduced in 1996 it has grown quite rapidly and
it has now been standardized by the famous IETF
or the Internet Engineering Task Force. What Is
H.323? It is also important to find out the
right answer to the question as to what is H.323.
H.323 is also another application layer protocol
and it is used for the purposes of VoIP. It finds
a number of uses as far as video conferencing
and audio conferencing is concerned. It however,
is not used for other purposes like file sharing,
application sharing or online
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games. It is mainly focused in areas of
multimedia conferencing. It is less complex when
compared to SIP. Hence when talking about H.323
vs sip, this important point should always be
kept in mind. It also came into the market in
1996 and it was approved by the International
Telecommunication Union. It has now become the
standard as far as multimedia conferencing over
IP is concerned. Unlike SIP, H.323 does not work
on a text based protocol. It is basically a
binary protocol. In other words, messages are
transmitted using binary codes. It therefore
could be very useful for narrowband connections.
It has a high level of interoperability. It also
has other benefits and features such as NAT
traversal. It is perfectly suited for video
conferencing, load balancing and for multiple
addressing schemes. What Are The Basic
Differences? Now that we have a reasonably good
understanding of both the protocols, we can try
and move away from the subject what is H.323 vs
SIP. Instead we will try and list out the major
areas of differences between the two protocols.
Here are a few major areas of differences
between H.323 and SIP SIP is suitable when it
comes to instant messaging, file sharing, and
multimedia communicating and also for the
purposes of online gaming. It is also the most
sought after protocol for multimedia
conferencing. On the other hand, when we talk
about H.323 it basically takes care of only
multimedia conferencing. Therefore when there is
a discussion on sip vs h.323 video conferencing,
it has been found that SIP always has a better
acceptability and is better when compared to
H.323. There is no doubt that H.323 has a much
smaller scope of operation when compared to SIP.
However, in terms of complexities and ease of
use, many end users feel that H.323 could be a
better option. Hence, this is an interesting
point to be borne in mind while trying to find
the difference between H.323 and sip. When it
comes to interoperability, it has been proven
time and again that H.323 is always a better
choice. In terms of reliability too, H.323 could
be better. This is mainly because it has inbuilt
features to take care of failure of network
connections and devices. This kind of recovery
mechanism is found wanting in SIP.
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It also would be pertinent to mention that SIP is
a text based protocol. The messages are encoded
using ASCII characters. When it comes to H.323
binary codes are used for messaging. In terms of
readability there is no doubt that SIP scores
quite heavily over H.323. However, in terms of
bandwidth usage H.323 is always better because it
uses binary coding system. SIP does not have
the capability of doing load balancing which
H.323 provides. Further the addressing method
used in H.323 is quite flexible and not as rigid
as it is in SIP. SIP is capable of reading only
URI. H.323 on the other hand is capable of
supporting various other addresses such as E.164
numbers, email, mobile UIM, transport address and
so on. Which Service Providers Use Both? Both
H.323 and SIP have their own unique features and
advantages. Hence reputed service providers who
offer the best of unified communication platforms
make it a point to use both H.323 and SIP. If
you visit sites like ezTalks video conferencing,
you will find out that they use both the above
protocols. This is because such service providers
are strong both in video conferencing as well as
instant text messaging and other services. The
Final Word When it comes to evaluating H.323 vs
SIP, both have their own pros and cons. While
there is no doubt that SIP is the best option for
multimedia communication and conferencing, when
it comes to lowband connections, H.323 could
always be a much better choice, because it uses
binary codes. https//www.eztalks.com/video-confe
rence/what-is-difference-between-h323-and-sip.html