T.38 - Revision history

Clod Patry: I wrongly modified T38 page instead of NSE, so revert it

2012-05-28T15:49:42Z

I wrongly modified T38 page instead of NSE, so revert it

Clod Patry at 15:48, 28 May 2012

2012-05-28T15:48:23Z

Luc Morissette: /* TelcoBridges and T.38 */

2011-09-16T12:34:26Z

TelcoBridges and T.38

Ktrueman: initial content

2009-07-24T15:58:04Z

initial content

New page

According to Wikipedia, "T.38 fax relay standard was devised in 1998 as a way to permit faxes to be transported across IP networks between existing Group 3 (G3) fax terminals. T.4 and related fax standards were published by the ITU in 1980, before the rise of the internet. In the late 90s, [[VoIP]], or Voice over IP, began to gain ground as an alternative to the conventional [[PSTN|Public Switched Telephone Network]]. However, because most VoIP systems are optimized (through their use of bandwidth-saving compression) for voice rather than data calls, conventional fax machines worked poorly or not at all on them due to the network impairments such as delay, jitter, packet loss, and so on. Thus, some way of transmitting fax over IP was needed.

== TelcoBridges and T.38 ==
TelcoBridges provides native support for the T.38 fax relay standard. However, it requires the presence of the optional VoIP modules; these may be configured at initial device purchase or added later on.

TelcoBridges has developed [[TB Fax Server]], a solution that leverages T.38 to provide [[Fax over IP]] capabilities.

== References ==
*[http://en.wikipedia.org/wiki/T.38 Wikipedia article]

[[category:Glossary]]

@@ Line 1: / Line 1: @@
-NSE (Named Signaling Events) is a proprietary protocol to switch from voice to Passthru, without involving SIP. It uses a proprietary event, based on Named Telephony Events (NTE), (see 3.5 Payload Format from RFC2833). So NTE is not proprietary, but NSE is.
+According to Wikipedia, "T.38 fax relay standard was devised in 1998 as a way to permit faxes to be transported across IP networks between existing Group 3 (G3) fax terminals. T.4 and related fax standards were published by the ITU in 1980, before the rise of the internet. In the late 90s, VoIP, or Voice over IP, began to gain ground as an alternative to the conventional Public Switched Telephone Network. However, because most VoIP systems are optimized (through their use of bandwidth-saving compression) for voice rather than data calls, conventional fax machines worked poorly or not at all on them due to the network impairments such as delay, jitter, packet loss, and so on. Thus, some way of transmitting fax over IP was needed.
-== TelcoBridges and NSE ==
-TelcoBridges implementation currently only support NSE events:
+== TelcoBridges and T.38 ==
-<pre>
+TelcoBridges provides native support for the T.38 fax relay standard.
-(switch to passthru)
-(disable echo)
-(switch back to voice)
-</pre>
 == References ==
-*[http://tools.ietf.org/html/rfc2833 RFC 2833]
+*[http://en.wikipedia.org/wiki/T.38 Wikipedia article]
-*[https://supportforums.cisco.com/docs/DOC-1381 NSE article]
 [[category:Glossary]]