[SIPForum-discussion] TCP vs RTP

[lokesh agrawal]

Hi Alex,

Please make clear few points
1. No end-to-end protocol, including RTP, can ensure in-time delivery. RTP
does not define any mechanisms for recovering for packet loss
2. RTP can carry any data with real-time characteristics, such as
interactive audio and video. It can also be used for Text Conversation.
3. Services provided by RTP include: Payload-type identification, Sequence
numbering - PDU sequence number, Time stamping - allow synchronization and
jitter calculations, Delivery monitoring.
4. Applications using RTP are less sensitive to packet loss, but typically
very sensitive to delays, so UDP is a better choice than TCP for such
applications.
5. If you want to transfer data text (Non real) you hv to use TCP for
reliability.

If still u have any doubt please ask me.



Regards
Lokesh Agrawal
Member of Technical Staff
Persistent Systems Pvt. Ltd.



On 4/23/07, alexzhang at gdnt.com.cn <alexzhang at gdnt.com.cn> wrote:
>
>  Hi Lokesh,
>
> My question is: If RTP is based on the connectionless Oriented, can we say
> this protocol is only applicable to the Audio and video transporation? If we
> want to transfer data without any possible loss, is it reliable to use RTP?
>
> -- A l e x
>
>
>  ------------------------------
> *From:* discussion-bounces at sipforum.org [mailto:
> discussion-bounces at sipforum.org] *On Behalf Of *lokesh agrawal
> *Sent:* Monday, April 23, 2007 4:33 PM
> *To:* discussion at sipforum.org
> *Subject:* Re: [SIPForum-discussion] TCP vs RTP
>
>
>  Hi,
>
> First of all let me tell you that TCP and RTP both are both different
> purpose.
> VoIP data packets live in RTP (Real-Time Transport Protocol) packets which
> are inside UDP-IP packets
> TCP is more making/terminating connections and RTP is for payloads and
> data packets.
>
> VOIP data packets uses UDP, RTP and IP protocols for operation.
> We can use TCP(Connection Oriented) in place of UDP(connectionless) but
> VoIP doesn't use TCP because it is too heavy for real time applications and
> for voice it will add delay in packets as it needs ACK for each and every
> packet.
>
>
> Regards
> Lokesh Agrawal
> Persistent Systems Pvt. Ltd.
>
>
> On 4/23/07, William Prusty <williamp at techmahindra.com> wrote:
> >
> >  Whether TCP is capable to carry AUDIO , VIDEO data ?? if yes then why
> > we are using RTP in SIP to carry  AUDIO , VIDEO data
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Plz answer .
> >
> > ============================================================================================================================
> >
> > Disclaimer:
> >
> > This message and the information contained herein is proprietary and
> > confidential and subject to the Tech Mahindra policy statement, you may
> > review at http://www.techmahindra.com/Disclaimer.html externally and
> > http://tim.techmahindra.com/Disclaimer.html internally within Tech
> > Mahindra.
> >
> >
> > ============================================================================================================================
> >
> > _______________________________________________
> > This is the SIP Forum discussion mailing list
> > TO UNSUBSCRIBE, or edit your delivery options, please visit
> > http://sipforum.org/mailman/listinfo/discussion
> > Post to the list at discussion at sipforum.org
> >
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20070423/9395ee0b/attachment-0002.html>