[SIPForum-discussion] confussion about use of tcp/udp
Sandeep Mohapatra
sandeep01it22 at yahoo.co.in
Mon Jun 9 19:01:45 UTC 2008
Hello guys,
In SIP the request can go over TCP or UDP. However most of the stacks use UDP as default transport protocol because it has less bytes(8 bytes) and hence less traffic issues in compared to TCP(12 to 20 bytes).
However you can specifically implement the transport protocol by adding one parameter on the URI.
for example:
<sip:1233 at 10.250.200.50:5060;transport=UDP>
<sip:1233 at 10.250.200.50:5060;transport=udp>
<sip:1233 at 10.250.200.50:5060;transport=TCP>
<sip:1233 at 10.250.200.50:5060;transport=tcp>
Hope this clarify the issues.
Regards,
Sandeep
--- On Mon, 9/6/08, Francois Audet <audet at nortel.com> wrote:
From: Francois Audet <audet at nortel.com>
Subject: Re: [SIPForum-discussion] confussion about use of tcp/udp
To: "Samir Patni" <samir_patni at persistent.co.in>, "Neill Wilkinsonj" <neill.wilkinson at quortex.com>, khalikh at yahoo.com, discussion at sipforum..com
Cc: "kranti kumar" <kkril at cooltoad.com>
Date: Monday, 9 June, 2008, 9:53 PM
_filtered #yiv1927709437 {
font-family:Tahoma;}
_filtered #yiv1927709437 {
font-family:Calibri;}
_filtered #yiv1927709437 {
font-family:Trebuchet MS;}
_filtered #yiv1927709437 {margin:1.0in 1.0in 1.0in 1.0in;}
#yiv1927709437 A:link {
}
#yiv1927709437 SPAN.MSOHYPERLINK {
}
#yiv1927709437 A:visited {
}
#yiv1927709437 SPAN.MSOHYPERLINKFOLLOWED {
}
#yiv1927709437 P.MSOACETATE {
}
#yiv1927709437 LI.MSOACETATE {
}
#yiv1927709437 DIV.MSOACETATE {
}
#yiv1927709437 SPAN.BALLOONTEXTCHAR {
}
#yiv1927709437 P.MsoNormal {
FONT-SIZE:12pt;MARGIN:0in 0in 0pt;FONT-FAMILY:"Times New Roman";}
#yiv1927709437 LI.MsoNormal {
FONT-SIZE:12pt;MARGIN:0in 0in 0pt;FONT-FAMILY:"Times New Roman";}
#yiv1927709437 DIV.MsoNormal {
FONT-SIZE:12pt;MARGIN:0in 0in 0pt;FONT-FAMILY:"Times New Roman";}
#yiv1927709437 A:link {
COLOR:blue;TEXT-DECORATION:underline;}
#yiv1927709437 SPAN.MsoHyperlink {
COLOR:blue;TEXT-DECORATION:underline;}
#yiv1927709437 A:visited {
COLOR:purple;TEXT-DECORATION:underline;}
#yiv1927709437 SPAN.MsoHyperlinkFollowed {
COLOR:purple;TEXT-DECORATION:underline;}
#yiv1927709437 PRE {
FONT-SIZE:10pt;MARGIN:0in 0in 0pt;FONT-FAMILY:"Courier New";}
#yiv1927709437 P.MsoAcetate {
FONT-SIZE:8pt;MARGIN:0in 0in 0pt;FONT-FAMILY:Tahoma;}
#yiv1927709437 LI.MsoAcetate {
FONT-SIZE:8pt;MARGIN:0in 0in 0pt;FONT-FAMILY:Tahoma;}
#yiv1927709437 DIV.MsoAcetate {
FONT-SIZE:8pt;MARGIN:0in 0in 0pt;FONT-FAMILY:Tahoma;}
#yiv1927709437 SPAN.BalloonTextChar {
FONT-FAMILY:Tahoma;}
#yiv1927709437 SPAN.EmailStyle19 {
COLOR:#1f497d;FONT-FAMILY:Calibri;}
#yiv1927709437 SPAN.EmailStyle20 {
COLOR:navy;FONT-FAMILY:Arial;}
#yiv1927709437 DIV.Section1 {
}
It pretty much doesn't work like this in real
life.
You pick either TCP or UDP and in the case of UDP, pray
that you won't get fragmentation problems.
From: discussion-bounces at sipforum.org
[mailto:discussion-bounces at sipforum.org] On Behalf Of Samir
Patni
Sent: Monday, June 09, 2008 04:48
To: 'Neill
Wilkinsonj'; khalikh at yahoo.com; discussion at sipforum.com
Cc: 'kranti
kumar'
Subject: Re: [SIPForum-discussion] confussion about use of
tcp/udp
Hi All,
Can a call contain both TCP and
UDP messages.
From section 18.1.1
from rfc 3261 “If a request is within 200 bytes of the path MTU, or if it is largerthan 1300 bytes and the path MTU is unknown, the request MUST be sentusing an RFC 2914 [43] congestion controlled transport protocol, such
as TCP.”
Consider a scenario in which Invite is sent over UDP
and for some other subsequent request/response (say
A).
Within the same call the Request length is more
then 1300 bytes. Should this request A be sent over
TCP?
Has someone seen two transport layer
protocols used in the same call?
Thanks,
Samir Patni
From:
discussion-bounces at sipforum.org [mailto:discussion-bounces at sipforum.org]
On Behalf Of Neill
Wilkinsonj
Sent: Monday, June
09, 2008 12:45 PM
To:
khalikh at yahoo.com; discussion at sipforum.com
Cc: 'kranti kumar'
Subject: Re: [SIPForum-discussion]
confussion about use of tcp/udp
RTP
(voice) is always carried over UDP. There is one notable exception and I
believe Skype can sometimes use TCP to carry voice. TCP generally has some
undesirable properties (Head-of-Line blocking and long timers related to
connection state), which make it unsuitable for carry realtime traffic such as
voice.
SIP
signalling can travel over UDP or TCP, generally the UA(C) will choose one or
the other at the start of the interaction and the UA(S) will respond using the
same for the complete dialogue. That is my observation in
Practice.
Someone
else on the list more conversant with RFC which to confirm or
clarify?
Neill....;o)
From:
discussion-bounces at sipforum.org [mailto:discussion-bounces at sipforum.org]
On Behalf Of khalikh
uddin
Sent: 09 June 2008
07:18
To:
discussion at sipforum.com
Cc:
kranti kumar
Subject:
[SIPForum-discussion] confussion about use of
tcp/udp
hai
all
can anybody tell me
*when a sip enabled end device
opens a TCP connection and when it uses UDP to send *REQ/RESPONSES to
proxy or other UA.
*can it use both in a aparticular diloge i.e
to send INVITE use TCP and to send ACK
use
UDP.
*Can we force
it to use TCP/UDP.
*For media transmission SIP uses only tcp.Is this
true.
_______________________________________________
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
From Chandigarh to Chennai - find friends all over India. Go to http://in.promos.yahoo.com/groups/citygroups/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20080610/f7b4bda8/attachment-0002.html>
More information about the discussion
mailing list