Re: Question about IGMP host implementation
"V, Magesh (Magesh)" <[email protected]> Wed, 12 Oct 2011 10:52:58 +0530
| Newsgroups | gmane.ietf.magma |
|---|---|
| Message-ID | <05D3B4AA7527D74EBF4921238463575321641601BA@INBANSXCHMBSA2.in.alcatel-lucent.com> |
--===============1335519200773539082== Content-Language: en-US Content-Type: multipart/alternative; boundary="_000_05D3B4AA7527D74EBF4921238463575321641601BAINBANSXCHMBSA_" --_000_05D3B4AA7527D74EBF4921238463575321641601BAINBANSXCHMBSA_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable To the best of my knowledge the host does not care about the source-ip of t= he query for it to respond. I've seen this work always. OTOH, the igmp router needs to do this check for the reports received becau= se they come from the untrusted side of the n/w. Thanks, Magesh. ________________________________ From: [email protected] [mailto:[email protected]] On Behalf Of K= unal Shah Sent: Wednesday, October 12, 2011 6:09 AM To: [email protected] Subject: [magma] Question about IGMP host implementation Hi all, Can an IGMPv2 host respond to a general query originated from a subnet othe= r then its own?? RFC 2236 states: ""query received" occurs when the host receives either a valid General Membership Query message, or a valid Group-Specific Membership Query message. To be valid, the Query message must be at least 8 octets long, and have a correct IGMP checksum. The group address in the IGMP header must either be zero (a General Query) or a valid multicast group address (a Group-Specific Query)" There is no requirement for the source address to be on the same subnet as = the host. Thanks, Kunal --_000_05D3B4AA7527D74EBF4921238463575321641601BAINBANSXCHMBSA_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable <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=3D"http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=3DContent-Type content=3D"text/html; charset=3Dus-ascii"> <meta name=3DGenerator content=3D"Microsoft Word 11 (filtered medium)"> <!--[if !mso]> <style> v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} </style> <![endif]--> <style> <!-- /* Font Definitions */ @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:0in; margin-bottom:.0001pt; font-size:12.0pt; font-family:"Times New Roman";} a:link, span.MsoHyperlink {color:blue; text-decoration:underline;} a:visited, span.MsoHyperlinkFollowed {color:#606420; text-decoration:underline;} p.emailquote, li.emailquote, div.emailquote {mso-margin-top-alt:auto; margin-right:0in; mso-margin-bottom-alt:auto; margin-left:1.0pt; border:none; padding:0in; font-size:12.0pt; font-family:"Times New Roman";} span.EmailStyle18 {mso-style-type:personal-reply; font-family:Arial; color:navy;} @page Section1 {size:595.3pt 841.9pt; margin:1.0in 1.25in 1.0in 1.25in;} div.Section1 {page:Section1;} --> </style> <!-- converted from rtf --><!--[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=3DEN-US link=3Dblue vlink=3D"#606420"> <div class=3DSection1> <p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span style= =3D'font-size: 10.0pt;font-family:Arial;color:navy'>To the best of my knowledge the host d= oes not care about the source-ip of the query for it to respond. I’ve see= n this work always.<o:p></o:p></span></font></p> <p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span style= =3D'font-size: 10.0pt;font-family:Arial;color:navy'>OTOH, the igmp router needs to do this check for the reports received because they come from the untrusted side of= the n/w.<o:p></o:p></span></font></p> <p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span style= =3D'font-size: 10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p> <p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span style= =3D'font-size: 10.0pt;font-family:Arial;color:navy'>Thanks,<o:p></o:p></span></font></p> <p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span style= =3D'font-size: 10.0pt;font-family:Arial;color:navy'>Magesh.<o:p></o:p></span></font></p> <p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span style= =3D'font-size: 10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p> <div> <div class=3DMsoNormal align=3Dcenter style=3D'margin-left:.5in;text-align:= center'><font size=3D3 face=3D"Times New Roman"><span style=3D'font-size:12.0pt'> <hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1> </span></font></div> <p class=3DMsoNormal style=3D'margin-left:.5in'><b><font size=3D2 face=3DTa= homa><span style=3D'font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span>= </font></b><font size=3D2 face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> [email protected] [mailto:[email protected]] <b><span style=3D'font-weight:bold'>On Behalf Of </span></b>Kunal Shah<br> <b><span style=3D'font-weight:bold'>Sent:</span></b> Wednesday, October 12,= 2011 6:09 AM<br> <b><span style=3D'font-weight:bold'>To:</span></b> [email protected]<br> <b><span style=3D'font-weight:bold'>Subject:</span></b> [magma] Question ab= out IGMP host implementation</span></font><o:p></o:p></p> </div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D3 face=3D"Time= s New Roman"><span style=3D'font-size:12.0pt'><o:p> </o:p></span></font></p> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'>Hi all,<o:p></o:p></span></fon= t></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'> <o:p></o:p></span></font= ></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'>Can an IGMPv2 host respond to = a general query originated from a subnet other then its own?? RFC 2236 states= : <o:p></o:p></span></font></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'> <o:p></o:p></span></font= ></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'>"</span></font><font size= =3D2 face=3D"Courier New"><span style=3D'font-size:10.0pt;font-family:"Courier N= ew"'>"query received" occurs when the host receives either a valid<br> General Membership Query message, or a valid Group-Specific<br> Membership Query message. To be valid, the Q= uery message must be<br> at least 8 octets long, and have a correct IGMP checksum. The<br> group address in the IGMP header must either be ze= ro (a General<br> Query) or a valid multicast group address (a Group= -Specific Query)</span></font><font size=3D2 face=3DArial><span style=3D'font-size:10= .0pt; font-family:Arial'>" <o:p></o:p></span></font></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'> <o:p></o:p></span></font= ></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'>There is no requirement for th= e source address to be on the same subnet as the host.<o:p></o:p></span></fon= t></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'> <o:p></o:p></span></font= ></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'>Thanks,<o:p></o:p></span></fon= t></p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'>Kunal<o:p></o:p></span></font>= </p> </div> <div> <p class=3DMsoNormal style=3D'margin-left:.5in'><font size=3D2 face=3DArial= ><span style=3D'font-size:10.0pt;font-family:Arial'> <o:p></o:p></span></font= ></p> </div> </div> </body> </html> --_000_05D3B4AA7527D74EBF4921238463575321641601BAINBANSXCHMBSA_-- --===============1335519200773539082== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ magma mailing list [email protected] https://www.ietf.org/mailman/listinfo/magma --===============1335519200773539082==--