RE: TTL for the bottom VC label
"Busschbach, Peter B (Peter)" <[email protected]> Wed, 2 Jul 2003 17:55:29 -0400
| Newsgroups | gmane.ietf.ppvpn,gmane.ietf.mpls |
|---|---|
| Message-ID | <B99995113B318D44BBE87DC50092EDA95EB421@nj7460exch006u.ho.lucent.com> |
This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ------_=_NextPart_001_01C340E4.A7146F22 Content-Type: text/plain Hariom, The TTL value of the VC (PW) Label was discussed on the mailing list in the first half of May (see archive). The conclusion was: "The setting of the TTL value in the PW label is application dependent, however in a strict point to point application the TTL should be appropriately set to 2" As you see, the text leaves open the possibility that PWs are spliced together to form connections across multiple hops. In that case, the intermediate hops would switch based on the PW label (and decrease the PW Label's TTL value in the process) Peter -----Original Message----- From: Hariom Prasad [mailto:[email protected]] Sent: Wednesday, July 02, 2003 5:11 PM To: [email protected] Cc: [email protected] Subject: TTL for the bottom VC label All, Generally on the ingress edge hop ( for vpn cases ) 2 labels get pushed, upper tunnel/lsp label and the bottom VC label. The TTL for the upper label should be adequate enough for the hop-count of tunnel/lsp. What should be the TTL value of bottom label.. One possibility is to set it to a value same as the top label..Other possibility is to set it to "1" which ensures that VC does'nt travel more than one hop after it is exposed.. I would really appreciate if someone could point out what is recommended value if there is one... Thanks with regards, homp _____ Do you Yahoo!? SBC <http://pa.yahoo.com/*http://rd.yahoo.com/evt=1207/*http://promo.yahoo.com/sbc/> Yahoo! DSL - Now only $29.95 per month! ------_=_NextPart_001_01C340E4.A7146F22 Content-Type: text/html <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"> <META content="MSHTML 5.50.4923.2500" name=GENERATOR></HEAD> <BODY> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2>Hariom,</FONT></SPAN></DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2></FONT></SPAN> </DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2>The TTL value of the VC (PW) Label was discussed on the mailing list in the first half of May (see archive). The conclusion was:</FONT></SPAN></DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2></FONT></SPAN> </DIV> <DIV><SPAN class=951153721-02072003>"The setting of the TTL value in the PW label is application dependent, however in a strict point to point application the TTL should be appropriately set to 2"</SPAN></DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2></FONT></SPAN> </DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2>As you see, the text leaves open the possibility that PWs are spliced together to form connections across multiple hops. In that case, the intermediate hops would switch based on the PW label (and decrease the PW Label's TTL value in the process)</FONT></SPAN></DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2></FONT></SPAN> </DIV> <DIV><SPAN class=951153721-02072003><FONT face=Arial size=2>Peter</FONT></SPAN></DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid"> <DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma size=2>-----Original Message-----<BR><B>From:</B> Hariom Prasad [mailto:[email protected]]<BR><B>Sent:</B> Wednesday, July 02, 2003 5:11 PM<BR><B>To:</B> [email protected]<BR><B>Cc:</B> [email protected]<BR><B>Subject:</B> TTL for the bottom VC label<BR><BR></FONT></DIV> <DIV>All,</DIV> <DIV> </DIV> <DIV>Generally on the ingress edge hop ( for vpn cases ) 2 labels get pushed, upper tunnel/lsp label and the bottom VC label. The TTL for the upper label should be adequate enough for the hop-count of tunnel/lsp. What should be the TTL value of bottom label..</DIV> <DIV> </DIV> <DIV>One possibility is to set it to a value same as the top label..Other possibility is to set it to "1" which ensures that VC does'nt travel more than one hop after it is exposed..</DIV> <DIV> </DIV> <DIV>I would really appreciate if someone could point out what is recommended value if there is one... Thanks</DIV> <DIV> </DIV> <DIV>with regards,</DIV> <DIV>homp</DIV> <DIV> </DIV> <P> <HR SIZE=1> Do you Yahoo!?<BR><A href="http://pa.yahoo.com/*http://rd.yahoo.com/evt=1207/*http://promo.yahoo.com/sbc/">SBC Yahoo! DSL</A> - Now only $29.95 per month!</BLOCKQUOTE></BODY></HTML> ------_=_NextPart_001_01C340E4.A7146F22--