Re: H.248-controlled T.38 configurations: SDP- vs Property-based H.248 signalling
"Schwarz, Albrecht (Albrecht)" <[email protected]> Thu, 2 Aug 2012 10:05:04 +0200
| Newsgroups | gmane.ietf.megaco |
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| Message-ID | <5F7BCCF5541B7444830A2288ABBEBC96218B57EC14@FRMRSSXCHMBSD2.dc-m.alcatel-lucent.com> |
--===============5190213354854115612== Content-Language: en-US Content-Type: multipart/alternative; boundary="_000_5F7BCCF5541B7444830A2288ABBEBC96218B57EC14FRMRSSXCHMBSD_" --_000_5F7BCCF5541B7444830A2288ABBEBC96218B57EC14FRMRSSXCHMBSD_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello Thomas, I followed the SIP Forum FoIP thread, but I fail to see that confirmation t= owards remote G3FE. Actually it's rather the opposite, see Kevin's reply to you: > (I did not find any definition of MMR format apart from "Modified > Modified Read" in T.38. However on Annex VI of T.30, MMR is defined as > the T.6 encoding. This also matches explanations in Wikipedia) > > *T38FaxTranscodingJBIG*: Indicates the ability to convert to/from JBIG > to reduce bandwidth. This > > is a boolean parameter (inclusion =3D true, exclusion =3D false). It is possible for a T.30<->T.38 gateway to provide these behaviors if desi= red, and the resulting T.38 bitstream would differ in some noticeable ways = from the T.30 bitstream. However, based on discussions with various knowled= geable parties during our previous work in this group, it appears that it i= s highly unusual for a T.38 implementation (gateway or terminal) to actuall= y perform any of these three functions. =F0 it's a gateway capability! =F0 all your three referred T.38 parameters are subject of the IM-MGW impl= ementation! and ALU supports the recommended default values by Table H.2/T.38 (which sh= ould be inline with your proposal). Hence, Kevin explicitly confirms this also as gateway capability! Regards, Albrecht From: Belling, Thomas (NSN - DE/Munich) [mailto:[email protected]] Sent: Mittwoch, 1. August 2012 16:46 To: Schwarz, Albrecht (Albrecht); [email protected] Subject: RE: H.248-controlled T.38 configurations: SDP- vs Property-based H= .248 signalling Dear Albrecht, Thanks for your comments. with respect to T38FaxFillBitRemoval, T38FaxTranscodingMMR and T38FaxTransc= odingJBIG SDP attributes, to which Notes 1 and 2 relate, I had some discus= sions at the SIP forum FoIP mailing list as you suggested. And it was confirmed that unless you do some "transcoding" of the payload w= ithin T.38 at the MGW, those properties relate to the remote CS FAX endpoin= t. However, people thought that not signaling those properties in H.248v4 m= ight be OK, because the default values which then apply are likely to be su= pported by any receiving CS endpoint. The only open issue where I did not y= et receive any reply is whether any harm is done if the CS endpoint behaves= differently when sending. Thomas From: 3GPP_TSG_CT_WG3 - Core Network and Terminals WG 3 [mailto:3GPP_TSG_CT= [email protected]] On Behalf Of ext Schwarz, Albrecht (Albrecht) Sent: Wednesday, August 01, 2012 4:17 PM To: [email protected] Subject: H.248-controlled T.38 configurations: SDP- vs Property-based H.248= signalling [Cc'd megaco list due to H.248.2] The T.38 parameters as defined by ITU-T T.38 are related to a T.38 endpoint= implementation, such as the T.38 user plane interworking function as e.g. = located in an H.248 IP-to-TDM media gateway (e.g. 3GPP IM-MGW). There are fundamentally two signaling options for such T.38 configurations: 1. SDP-based: using T.38 Annex D defined SDP elements embedded in H.248 d= escriptors 2. Property-based: using H.248.2, IP Fax package defined properties, such= as specified by clauses 10.1.3 to 10.1.7 Both H.248 signalling options are basically equivalent, - independent of SD= P- or Property-based signaling elements. The signaling elements relate to t= he T.38 endpoint, but NOT to any remote G3FE. [Note: the H.248 IP fax package version 1 (from 2005/2007) does not yet con= tain the latest T.38V4 (2010) parameter. But this aspect is irrelevant in t= his discussion due to the proposal in 3GPP for the SDP-based method.] Thus, all "T.38 SDP attributes" (in C3-121327) are related to gateway capabilitie= s (such as supported T.38 configurations by an IM-MGW implementation) (NOTE= : attached is T.38 Table B.1 for H.323 gateways, which again underlines the= relation to gateway capabilities). The MGC / MGCF may be either 1. aware of the supported T.38 configuration(s) by his associated MGs or 2. unaware. Awareness may be achieved via auditing or configuration management. Unawareness is basically possible, but may lead to inefficient or even inef= fective H.248 scenarios for T.38. Dependent on the amount of "supported T.38 configuration(s)" knowledge at M= GC level would be the content of the SIP-level SDP O/A procedures. Conclusions for C3-121327 (http://www.3gpp.org/ftp/tsg_ct/WG3_interworking_= ex-CN3/TSGC3_70_Chicago/Docs/C3-121327.zip): NOTEs 1 and 2 in Table X.3.1 are incorrect in my opinion. The text related to "remote CS FAX equipment" (term should be anyway replac= ed by term G3FE) should be just deleted. And there would be correspondent c= hanges at other tables. -Albrecht --_000_5F7BCCF5541B7444830A2288ABBEBC96218B57EC14FRMRSSXCHMBSD_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <META HTTP-EQUIV=3D"Content-Type" CONTENT=3D"text/html; charset=3Diso-8859-= 1"> <html xmlns:v=3D"urn:schemas-microsoft-com:vml" xmlns:o=3D"urn:schemas-micr= osoft-com:office:office" xmlns:w=3D"urn:schemas-microsoft-com:office:word" = xmlns:m=3D"http://schemas.microsoft.com/office/2004/12/omml" xmlns=3D"http:= //www.w3.org/TR/REC-html40"><head><meta name=3DGenerator content=3D"Microso= ft Word 12 (filtered medium)"><style><!-- /* Font Definitions */ @font-face {font-family:Wingdings; panose-1:5 0 0 0 0 0 0 0 0 0;} @font-face {font-family:Wingdings; panose-1:5 0 0 0 0 0 0 0 0 0;} @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;} @font-face {font-family:Tahoma; panose-1:2 11 6 4 3 5 4 4 2 4;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {margin:0cm; 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text-indent:-18.0pt;} ol {margin-bottom:0cm;} ul {margin-bottom:0cm;} --></style><!--[if gte mso 9]><xml> <o:shapedefaults v:ext=3D"edit" spidmax=3D"1026" /> </xml><![endif]--><!--[if gte mso 9]><xml> <o:shapelayout v:ext=3D"edit"> <o:idmap v:ext=3D"edit" data=3D"1" /> </o:shapelayout></xml><![endif]--></head><body lang=3DDE link=3Dblue vlink= =3Dpurple><div class=3DWordSection1><p class=3DMsoNormal><span lang=3DEN-US= style=3D'font-size:10.0pt;font-family:"Courier New";color:#993366'>Hello T= homas,<o:p></o:p></span></p><p class=3DMsoNormal><span lang=3DEN-US style= =3D'font-size:10.0pt;font-family:"Courier New";color:#993366'><o:p> </= o:p></span></p><p class=3DMsoNormal><span lang=3DEN-US style=3D'font-size:1= 0.0pt;font-family:"Courier New";color:#993366'>I followed the SIP Forum FoI= P thread, but I fail to see that confirmation towards remote G3FE.<o:p></o:= p></span></p><p class=3DMsoNormal><span lang=3DEN-US style=3D'font-size:10.= 0pt;font-family:"Courier New";color:#993366'>Actually it’s rather the= opposite, see Kevin’s reply to you:<o:p></o:p></span></p><p class=3D= MsoNormal><span lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Courier= New";color:#993366'><o:p> </o:p></span></p><p class=3DMsoPlainText><s= pan lang=3DEN-US>> (I did not find any definition of MMR format apart fr= om “Modified <o:p></o:p></span></p><p class=3DMsoPlainText><span lang= =3DEN-US>> Modified Read” in T.38. However on Annex VI of T.30, MM= R is defined as <o:p></o:p></span></p><p class=3DMsoPlainText><span lang=3D= EN-US>> the T.6 encoding. This also matches explanations in Wikipedia)<o= :p></o:p></span></p><p class=3DMsoPlainText><span lang=3DEN-US>><o:p>&nb= sp;</o:p></span></p><p class=3DMsoPlainText><span lang=3DEN-US>> *T38Fax= TranscodingJBIG*: Indicates the ability to convert to/from JBIG <o:p></o:p>= </span></p><p class=3DMsoPlainText><span lang=3DEN-US>> to reduce bandwi= dth. This<o:p></o:p></span></p><p class=3DMsoPlainText><span lang=3DEN-US>&= gt;<o:p> </o:p></span></p><p class=3DMsoPlainText><span lang=3DEN-US>&= gt; is a boolean parameter (inclusion =3D true, exclusion =3D false).<o:p><= /o:p></span></p><p class=3DMsoPlainText><span lang=3DEN-US><o:p> </o:p= ></span></p><p class=3DMsoPlainText><span lang=3DEN-US>It is <span style=3D= 'color:red'>possible for a T.30<->T.38 gateway</span> to <span style= =3D'color:red'>provide these behaviors if desired</span>, and the resulting= T.38 bitstream would differ in some noticeable ways from the T.30 bitstrea= m. However, based on discussions with various knowledgeable parties during = our previous work in this group, it appears that it is highly unusual for a= T.38 implementation (gateway or terminal) to actually perform any of these= three functions.<o:p></o:p></span></p><p class=3DMsoNormal><span lang=3DEN= -US style=3D'font-size:10.0pt;font-family:"Courier New";color:#993366'><o:p= > </o:p></span></p><p class=3DMsoNormal><span lang=3DEN-US style=3D'fo= nt-size:10.0pt;font-family:"Courier New";color:#993366'><o:p> </o:p></= span></p><p class=3DMsoListParagraph style=3D'text-indent:-18.0pt;mso-list:= l1 level1 lfo7'><![if !supportLists]><span lang=3DEN-US style=3D'font-size:= 10.0pt;font-family:Wingdings;color:#993366'><span style=3D'mso-list:Ignore'= >=F0<span style=3D'font:7.0pt "Times New Roman"'> </span></span></spa= n><![endif]><span lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Couri= er New";color:#993366'>it’s a gateway capability!<o:p></o:p></span></= p><p class=3DMsoListParagraph style=3D'text-indent:-18.0pt;mso-list:l1 leve= l1 lfo7'><![if !supportLists]><span lang=3DEN-US style=3D'font-size:10.0pt;= font-family:Wingdings;color:#993366'><span style=3D'mso-list:Ignore'>=F0<sp= an style=3D'font:7.0pt "Times New Roman"'> </span></span></span><![en= dif]><span lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Courier New"= ;color:#993366'>all your three referred T.38 parameters are subject of the = IM-MGW implementation!<o:p></o:p></span></p><p class=3DMsoNormal><span lang= =3DEN-US style=3D'font-size:10.0pt;font-family:"Courier New";color:#993366'= >and ALU supports the recommended default values by Table H.2/T.38 (which s= hould be inline with your proposal).<o:p></o:p></span></p><p class=3DMsoNor= mal><span lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Courier New";= color:#993366'><o:p> </o:p></span></p><p class=3DMsoNormal><span lang= =3DEN-US style=3D'font-size:10.0pt;font-family:"Courier New";color:#993366'= >Hence, Kevin explicitly confirms this also as gateway capability!<o:p></o:= p></span></p><p class=3DMsoNormal><span lang=3DEN-US style=3D'font-size:10.= 0pt;font-family:"Courier New";color:#993366'><o:p> </o:p></span></p><p= class=3DMsoNormal><span lang=3DEN-US style=3D'font-size:10.0pt;font-family= :"Courier New";color:#993366'>Regards,<o:p></o:p></span></p><p class=3DMsoN= ormal><span lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Courier New= ";color:#993366'>Albrecht<o:p></o:p></span></p><p class=3DMsoNormal><span s= tyle=3D'font-size:10.0pt;font-family:"Courier New";color:#993366'><o:p>&nbs= p;</o:p></span></p><p class=3DMsoNormal><span style=3D'font-size:10.0pt;fon= t-family:"Courier New";color:#993366'><o:p> </o:p></span></p><p class= =3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier New";colo= r:#993366'><o:p> </o:p></span></p><p class=3DMsoNormal><span style=3D'= font-size:10.0pt;font-family:"Courier New";color:#993366'><o:p> </o:p>= </span></p><div><div style=3D'border:none;border-top:solid #B5C4DF 1.0pt;pa= dding:3.0pt 0cm 0cm 0cm'><p class=3DMsoNormal><b><span lang=3DEN-US style= =3D'font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><sp= an lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Tahoma","sans-serif"= '> Belling, Thomas (NSN - DE/Munich) [mailto:[email protected]] <br><b= >Sent:</b> Mittwoch, 1. August 2012 16:46<br><b>To:</b> Schwarz, Albrecht (= Albrecht); [email protected]<br><b>Subject:</b> RE: H.248-contr= olled T.38 configurations: SDP- vs Property-based H.248 signalling<o:p></o:= p></span></p></div></div><p class=3DMsoNormal><o:p> </o:p></p><p class= =3DMsoNormal><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Cali= bri","sans-serif";color:#1F497D'>Dear Albrecht,<o:p></o:p></span></p><p cla= ss=3DMsoNormal><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Ca= libri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=3DM= soNormal><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Calibri"= ,"sans-serif";color:#1F497D'>Thanks for your comments.<o:p></o:p></span></p= ><p class=3DMsoNormal><span lang=3DEN-US style=3D'font-size:11.0pt;font-fam= ily:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p cl= ass=3DMsoNormal><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"C= alibri","sans-serif";color:#1F497D'>with respect to T38FaxFillBitRemoval, T= 38FaxTranscodingMMR and T38FaxTranscodingJBIG SDP attributes, to which Note= s 1 and 2 relate, I had some discussions at the SIP forum FoIP mailin= g list as you suggested.<o:p></o:p></span></p><p class=3DMsoNormal><span la= ng=3DEN-US style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";col= or:#1F497D'><o:p> </o:p></span></p><p class=3DMsoNormal><span lang=3DE= N-US style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F= 497D'>And it was confirmed that unless you do some “transcoding”= ; of the payload within T.38 at the MGW, those properties relate to the rem= ote CS FAX endpoint. However, people thought that not signaling those prope= rties in H.248v4 might be OK, because the default values which then apply a= re likely to be supported by any receiving CS endpoint. The only open issue= where I did not yet receive any reply is whether any harm is done if the C= S endpoint behaves differently when sending.<o:p></o:p></span></p><p class= =3DMsoNormal><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Cali= bri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=3DMso= Normal><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Calibri","= sans-serif";color:#1F497D'>Thomas<o:p></o:p></span></p><p class=3DMsoNormal= ><span lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Calibri","sans-s= erif";color:#1F497D'><o:p> </o:p></span></p><p class=3DMsoNormal><span= lang=3DEN-US style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";= color:#1F497D'><o:p> </o:p></span></p><p class=3DMsoNormal><span lang= =3DEN-US style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color= :#1F497D'><o:p> </o:p></span></p><div><div style=3D'border:none;border= -top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=3DMsoNormal><b= ><span lang=3DEN-US style=3D'font-size:10.0pt;font-family:"Tahoma","sans-se= rif"'>From:</span></b><span lang=3DEN-US style=3D'font-size:10.0pt;font-fam= ily:"Tahoma","sans-serif"'> 3GPP_TSG_CT_WG3 - Core Network and Terminals WG= 3 [mailto:[email protected]] <b>On Behalf Of </b>ext Schwarz, = Albrecht (Albrecht)<br><b>Sent:</b> Wednesday, August 01, 2012 4:17 PM<br><= b>To:</b> [email protected]<br><b>Subject:</b> H.248-controlled= T.38 configurations: SDP- vs Property-based H.248 signalling<o:p></o:p></s= pan></p></div></div><p class=3DMsoNormal><o:p> </o:p></p><div><p class= =3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier New";colo= r:#002060'>[Cc’d megaco list due to H.248.2]</span><span style=3D'fon= t-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><= p class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier Ne= w";color:#002060'> </span><span style=3D'font-size:10.0pt;font-family:= "Courier New"'><o:p></o:p></span></p></div><div><p class=3DMsoNormal><span = style=3D'font-size:10.0pt;font-family:"Courier New";color:#002060'>The <b>T= .38 parameters</b> as defined by ITU-T T.38 are related to a <b>T.38 endpoi= nt implementation</b>, such as the <b>T.38 user plane interworking function= </b> as e.g. located in an H.248 IP-to-TDM media gateway (e.g. 3GPP IM-MGW)= .</span><span style=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o= :p></span></p></div><div><p class=3DMsoNormal><span style=3D'font-size:10.0= pt;font-family:"Courier New";color:#002060'> </span><span style=3D'fon= t-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><= p class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier Ne= w";color:#002060'>There are fundamentally two signaling options for such T.= 38 configurations:</span><span style=3D'font-size:10.0pt;font-family:"Couri= er New"'><o:p></o:p></span></p></div><ol start=3D1 type=3Da><li class=3DMso= Normal style=3D'color:#002060;mso-margin-top-alt:auto;mso-margin-bottom-alt= :auto;mso-list:l2 level1 lfo3'><b><span style=3D'font-size:10.0pt;font-fami= ly:"Courier New"'>SDP-based</span></b><span style=3D'font-size:10.0pt;font-= family:"Courier New"'>: using <b>T.38 Annex D</b> defined SDP elements embe= dded in H.248 descriptors<o:p></o:p></span></li><li class=3DMsoNormal style= =3D'color:#002060;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-li= st:l2 level1 lfo3'><b><span style=3D'font-size:10.0pt;font-family:"Courier = New"'>Property-based</span></b><span style=3D'font-size:10.0pt;font-family:= "Courier New"'>: using <b>H.248.2, IP Fax package</b> defined properties, s= uch as specified by clauses 10.1.3 to 10.1.7<o:p></o:p></span></li></ol><di= v><p class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Calibri= ","sans-serif";color:#002060'> </span><span style=3D'font-size:10.0pt;= font-family:"Courier New"'><o:p></o:p></span></p></div><div><p class=3DMsoN= ormal><span style=3D'font-size:10.0pt;font-family:"Courier New";color:#0020= 60'>Both H.248 signalling options are basically equivalent, - independent o= f SDP- or Property-based signaling elements. The signaling elements relate = to the T.38 endpoint, but NOT to any remote G3FE.</span><span style=3D'font= -size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><p= class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier New= ";color:#002060'>[Note: the H.248 IP fax package version 1 (from 2005/2007)= does not yet contain the latest T.38V4 (2010) parameter. But this aspect i= s irrelevant in this discussion due to the proposal in 3GPP for the SDP-bas= ed method.]</span><span style=3D'font-size:10.0pt;font-family:"Courier New"= '><o:p></o:p></span></p></div><div><p class=3DMsoNormal><span style=3D'font= -size:10.0pt;font-family:"Calibri","sans-serif";color:#002060'> </span= ><span style=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></sp= an></p></div><div><p class=3DMsoNormal><span style=3D'font-size:10.0pt;font= -family:"Courier New";color:#002060'>Thus,</span><span style=3D'font-size:1= 0.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><p class= =3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier New";colo= r:#002060'>all “T.38 SDP attributes” (in C3-121327) are related= to gateway capabilities (such as supported T.38 configurations by an IM-MG= W implementation) (NOTE: attached is T.38 Table B.1 for H.323 gateways, whi= ch again underlines the relation to gateway capabilities).</span><span styl= e=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></di= v><div><p class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Co= urier New";color:#002060'>The MGC / MGCF may be either</span><span style=3D= 'font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><o= l start=3D1 type=3Da><li class=3DMsoNormal style=3D'color:#002060;mso-margi= n-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo6'><span st= yle=3D'font-size:10.0pt;font-family:"Courier New"'>aware of the supported T= .38 configuration(s) by his associated MGs or<o:p></o:p></span></li><li cla= ss=3DMsoNormal style=3D'color:#002060;mso-margin-top-alt:auto;mso-margin-bo= ttom-alt:auto;mso-list:l0 level1 lfo6'><span style=3D'font-size:10.0pt;font= -family:"Courier New"'>unaware.<o:p></o:p></span></li></ol><div><p class=3D= MsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier New";color:#= 002060'>Awareness may be achieved via auditing or configuration management.= </span><span style=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o:= p></span></p></div><div><p class=3DMsoNormal><span style=3D'font-size:10.0p= t;font-family:"Courier New";color:#002060'>Unawareness is basically possibl= e, but may lead to inefficient or even ineffective H.248 scenarios for T.38= .</span><span style=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o= :p></span></p></div><div><p class=3DMsoNormal><span style=3D'font-size:10.0= pt;font-family:"Courier New";color:#002060'>Dependent on the amount of R= 20;supported T.38 configuration(s)” knowledge at MGC level would be t= he content of the SIP-level SDP O/A procedures.</span><span style=3D'font-s= ize:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><p c= lass=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Calibri","san= s-serif";color:#002060'> </span><span style=3D'font-size:10.0pt;font-f= amily:"Courier New"'><o:p></o:p></span></p></div><div><p class=3DMsoNormal>= <span style=3D'font-size:10.0pt;font-family:"Courier New";color:#002060'>Co= nclusions for <b>C3-121327</b> (<a href=3D"http://www.3gpp.org/ftp/tsg_ct/W= G3_interworking_ex-CN3/TSGC3_70_Chicago/Docs/C3-121327.zip">http://www.3gpp= .org/ftp/tsg_ct/WG3_interworking_ex-CN3/TSGC3_70_Chicago/Docs/C3-121327.zip= </a>):</span><span style=3D'font-size:10.0pt;font-family:"Courier New"'><o:= p></o:p></span></p></div><div><p class=3DMsoNormal><span style=3D'font-size= :10.0pt;font-family:"Courier New";color:#002060'>NOTEs 1 and 2 in Table X.3= .1 are incorrect in my opinion.</span><span style=3D'font-size:10.0pt;font-= family:"Courier New"'><o:p></o:p></span></p></div><div><p class=3DMsoNormal= ><span style=3D'font-size:10.0pt;font-family:"Courier New";color:#002060'>T= he <b>text</b> related to “remote CS FAX equipment” (term shoul= d be anyway replaced by term G3FE) should be just <b>deleted</b>. And there= would be correspondent changes at other tables.</span><span style=3D'font-= size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><p = class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Calibri","sa= ns-serif";color:#002060'> </span><span style=3D'font-size:10.0pt;font-= family:"Courier New"'><o:p></o:p></span></p></div><div><p class=3DMsoNormal= ><span style=3D'font-size:10.0pt;font-family:"Courier New";color:#002060'>-= Albrecht</span><span style=3D'font-size:10.0pt;font-family:"Courier New"'><= o:p></o:p></span></p></div><div><p class=3DMsoNormal><span style=3D'font-si= ze:10.0pt;font-family:"Calibri","sans-serif";color:#002060'> </span><s= pan style=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span>= </p></div><div><p class=3DMsoNormal><span style=3D'font-size:10.0pt;font-fa= mily:"Calibri","sans-serif";color:#C00000'> </span><span style=3D'font= -size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p></div><div><p= class=3DMsoNormal><span style=3D'font-size:10.0pt;font-family:"Courier New= "'><o:p> </o:p></span></p></div><div><p class=3DMsoNormal><span style= =3D'font-size:10.0pt;font-family:"Calibri","sans-serif"'> </span><span= style=3D'font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></p= ></div></div></body></html>= --_000_5F7BCCF5541B7444830A2288ABBEBC96218B57EC14FRMRSSXCHMBSD_-- --===============5190213354854115612== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Megaco mailing list [email protected] https://www.ietf.org/mailman/listinfo/megaco --===============5190213354854115612==--