Re: certificationZone Bridging White paper ! [7:37393]
SNIP The RIF is just referenced (not changed) in frames that are specifically routed. In other words, once the end station has found a route, it just puts it in the frame and the bridges just read it forwards or backwards and route accordingly. Could that be what he's getting at?? END SNIP I'm not sure what he's getting at really. I agree with your explanation above but also this would be the same process for a pure SRB also !!! I think it is fair to say that a Transparent bridge never adds or removes RIFS since it doesn't use one. But to use the expression in a SRT or SR/TL bridge is misleading and very confusing without a bit of an explanation of route selection. Thanks for the link. Fun with it ??? Doubtful. Phil. http://standards.ieee.org/getieee802/ Have fun with it! --- Priscilla Oppenheimer wrote: At 08:34 AM 3/6/02, Phil Barker wrote: Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route The RIF is just referenced (not changed) in frames that are specifically routed. In other words, once the end station has found a route, it just puts it in the frame and the bridges just read it forwards or backwards and route accordingly. Could that be what he's getting at?? On the other hand, I agree with you that on an explorer, an SRT bridge changes the RIF. SRT simply implies a couple things: 1) If the RII is zero, just perform normal Ethernet-style transparent bridging 2) If the RII is one and redundant bridges exits, use the spanning tree to determine which way to forward explorer frames. By the way, SRT is the only form of source route bridging that the IEEE ever standardized. And you can get it for free! ;-) It's in Annex C of IEEE 802.1D, which you can get here: http://standards.ieee.org/getieee802/ Have fun with it! Priscilla !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Priscilla Oppenheimer http://www.priscilla.com [EMAIL PROTECTED] __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37535t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: certificationZone Bridging White paper ! [7:37393]
Ken, What I was getting at was that the SRB part of the SRT bridge is still acting as a SRB bridge for those nodes on that side of the network. Therefore when end hosts on that network try to find a route through this bridge to other end hosts on the SRB side of the network the RIF field will be manipulated (for spanning and explorer packets). So to make the sweeping statement that RIF fields will never change on SRT bridges is very misleading to the newbie, (me in this instance). I conclude that it is safe to say that RIF will never be manipulated on 'Transparent only' Bridges since they don't exist. Thx for the replies, Ken. Phil. --- Sexton, Ken wrote: Phil, Can I therefore conclude that in a 'Source Route Transparent' Bridge the RIF field will indeed change ? Contrary to the whitepaper. On the above - In SRT mode, you are allowing the router to source route traffic and transparently bridge traffic on the same device (router), but any hosts on either bridging environment can not communicate amongst themselves. (i.e. a host on an SRB network cannot sent traffic destined for a host on the transparent side of the network). The SRT Bridge will never add or remove RIF information from a frame in order for the two technologies to communicate. This is where Source-route Translation bridging (SR/TLB) comes in. Now your above question needs some consideration. The router will now act as a RIF end station, where a RIF table will be built for end stations on the SRB side, and a forwarding table for the transparent side. By creating a virtual ring within the router, all the token to ethernet frame conversion will take place (i.e MTU, bit ordering, etc) before the frame is sent on its way. It makes no sense to set the RII bit to a 1 when sending the traffic to a transparent end host, as it will not understand what to do with it anyway. Hope this helps Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 9:02 AM To: [EMAIL PROTECTED] Subject: RE: certificationZone Bridging White paper ! [7:37393] Thanks Ken, SNIP2 The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. END SNIP2 Can I therefore conclude that in a 'Source Route Transparent' Bridge the RIF field will indeed change ? Contrary to the whitepaper. Phil. --- Sexton, Ken wrote: Phil, The first bit within the Source Address Field is normally the I/G bit, to define if the source address is individual (unicast) or group (multicast) address. In an SRB bridged environment, this one bit is used to indicate if any Routing Information Field (RIF) information is present in the Token frame following the SA field. This bit will be set by hosts with the SRB environment and used by bridges to indicate the above. The hosts will keep a forwarding table on how to reach any required destination host. If the host doesn't know how to get to a particular destination, it will send out an explorer frame (all routes explorer -ARE) or a Spanning tree explorer (SPE) frame to locate the destination. It will depending on your bridged environment which explorer frame is used. The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. The first bridge will add the first ring number, it's bridge number, and the ring number of the interface it going to send the explorer packet out of. When all said and done - the host will know how to reach that particular end host and include RIF information in the token frame. The RII, will tell the bridge that a RIF is present and forward the frame according to the RIF RC and RD fields. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 6:35 AM To: [EMAIL PROTECTED] Subject: certificationZone Bridging White paper ! [7:37393] Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame
RE: certificationZone Bridging White paper ! [7:37393]
Phil, Can I therefore conclude that in a 'Source Route Transparent' Bridge the RIF field will indeed change ? Contrary to the whitepaper. On the above - In SRT mode, you are allowing the router to source route traffic and transparently bridge traffic on the same device (router), but any hosts on either bridging environment can not communicate amongst themselves. (i.e. a host on an SRB network cannot sent traffic destined for a host on the transparent side of the network). The SRT Bridge will never add or remove RIF information from a frame in order for the two technologies to communicate. This is where Source-route Translation bridging (SR/TLB) comes in. Now your above question needs some consideration. The router will now act as a RIF end station, where a RIF table will be built for end stations on the SRB side, and a forwarding table for the transparent side. By creating a virtual ring within the router, all the token to ethernet frame conversion will take place (i.e MTU, bit ordering, etc) before the frame is sent on its way. It makes no sense to set the RII bit to a 1 when sending the traffic to a transparent end host, as it will not understand what to do with it anyway. Hope this helps Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 9:02 AM To: [EMAIL PROTECTED] Subject: RE: certificationZone Bridging White paper ! [7:37393] Thanks Ken, SNIP2 The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. END SNIP2 Can I therefore conclude that in a 'Source Route Transparent' Bridge the RIF field will indeed change ? Contrary to the whitepaper. Phil. --- Sexton, Ken wrote: Phil, The first bit within the Source Address Field is normally the I/G bit, to define if the source address is individual (unicast) or group (multicast) address. In an SRB bridged environment, this one bit is used to indicate if any Routing Information Field (RIF) information is present in the Token frame following the SA field. This bit will be set by hosts with the SRB environment and used by bridges to indicate the above. The hosts will keep a forwarding table on how to reach any required destination host. If the host doesn't know how to get to a particular destination, it will send out an explorer frame (all routes explorer -ARE) or a Spanning tree explorer (SPE) frame to locate the destination. It will depending on your bridged environment which explorer frame is used. The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. The first bridge will add the first ring number, it's bridge number, and the ring number of the interface it going to send the explorer packet out of. When all said and done - the host will know how to reach that particular end host and include RIF information in the token frame. The RII, will tell the bridge that a RIF is present and forward the frame according to the RIF RC and RD fields. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 6:35 AM To: [EMAIL PROTECTED] Subject: certificationZone Bridging White paper ! [7:37393] Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com [EMAIL PROTECTED] __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37580t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct
RE: certificationZone Bridging White paper ! [7:37393]
Phil, The first bit within the Source Address Field is normally the I/G bit, to define if the source address is individual (unicast) or group (multicast) address. In an SRB bridged environment, this one bit is used to indicate if any Routing Information Field (RIF) information is present in the Token frame following the SA field. This bit will be set by hosts with the SRB environment and used by bridges to indicate the above. The hosts will keep a forwarding table on how to reach any required destination host. If the host doesn't know how to get to a particular destination, it will send out an explorer frame (all routes explorer -ARE) or a Spanning tree explorer (SPE) frame to locate the destination. It will depending on your bridged environment which explorer frame is used. The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. The first bridge will add the first ring number, it's bridge number, and the ring number of the interface it going to send the explorer packet out of. When all said and done - the host will know how to reach that particular end host and include RIF information in the token frame. The RII, will tell the bridge that a RIF is present and forward the frame according to the RIF RC and RD fields. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 6:35 AM To: [EMAIL PROTECTED] Subject: certificationZone Bridging White paper ! [7:37393] Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37398t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: certificationZone Bridging White paper ! [7:37393]
Thanks Ken, SNIP2 The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. END SNIP2 Can I therefore conclude that in a 'Source Route Transparent' Bridge the RIF field will indeed change ? Contrary to the whitepaper. Phil. --- Sexton, Ken wrote: Phil, The first bit within the Source Address Field is normally the I/G bit, to define if the source address is individual (unicast) or group (multicast) address. In an SRB bridged environment, this one bit is used to indicate if any Routing Information Field (RIF) information is present in the Token frame following the SA field. This bit will be set by hosts with the SRB environment and used by bridges to indicate the above. The hosts will keep a forwarding table on how to reach any required destination host. If the host doesn't know how to get to a particular destination, it will send out an explorer frame (all routes explorer -ARE) or a Spanning tree explorer (SPE) frame to locate the destination. It will depending on your bridged environment which explorer frame is used. The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. The first bridge will add the first ring number, it's bridge number, and the ring number of the interface it going to send the explorer packet out of. When all said and done - the host will know how to reach that particular end host and include RIF information in the token frame. The RII, will tell the bridge that a RIF is present and forward the frame according to the RIF RC and RD fields. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 6:35 AM To: [EMAIL PROTECTED] Subject: certificationZone Bridging White paper ! [7:37393] Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com [EMAIL PROTECTED] __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37411t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: certificationZone Bridging White paper ! [7:37393]
At 08:34 AM 3/6/02, Phil Barker wrote: Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route The RIF is just referenced (not changed) in frames that are specifically routed. In other words, once the end station has found a route, it just puts it in the frame and the bridges just read it forwards or backwards and route accordingly. Could that be what he's getting at?? On the other hand, I agree with you that on an explorer, an SRT bridge changes the RIF. SRT simply implies a couple things: 1) If the RII is zero, just perform normal Ethernet-style transparent bridging 2) If the RII is one and redundant bridges exits, use the spanning tree to determine which way to forward explorer frames. By the way, SRT is the only form of source route bridging that the IEEE ever standardized. And you can get it for free! ;-) It's in Annex C of IEEE 802.1D, which you can get here: http://standards.ieee.org/getieee802/ Have fun with it! Priscilla !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37463t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: certificationZone Bridging White paper ! [7:37393]
At 09:52 AM 3/6/02, Sexton, Ken wrote: Phil, The first bit within the Source Address Field is normally the I/G bit, to define if the source address is individual (unicast) or group (multicast) A source address can't be a group address. Just a nit-picky comment. address. In an SRB bridged environment, this one bit is used to indicate if any Routing Information Field (RIF) information is present in the Token frame following the SA field. This bit will be set by hosts with the SRB environment and used by bridges to indicate the above. The hosts will keep a forwarding table on how to reach any required destination host. If the host doesn't know how to get to a particular destination, it will send out an explorer frame (all routes explorer -ARE) or a Spanning tree explorer (SPE) frame to locate the destination. It will depending on your bridged environment which explorer frame is used. The first SRB enabled bridge in the path (from originator to destination) will see that this is an explorer packet and add its route designator (RD) information to the RIF. The first bridge will add the first ring number, it's bridge number, and the ring number of the interface it going to send the explorer packet out of. When all said and done - the host will know how to reach that particular end host and include RIF information in the token frame. The RII, will tell the bridge that a RIF is present and forward the frame according to the RIF RC and RD fields. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Phil Barker [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 6:35 AM To: [EMAIL PROTECTED] Subject: certificationZone Bridging White paper ! [7:37393] Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37464t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: certificationZone Bridging White paper ! [7:37393]
In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route To comment of the above, the RII bit doesn't indicate whether the frame is a specific routed frame or whether it is a explorer frame. It only indicates whether the frame contains RIF information or not. The specifically routed frame indicator is within the RIF (first three bits of the RC field, known as the type or broadcast bits - 0xx = specifically routed frame, 10x = ARE frame, 11x = SPE frame). Maybe its the way its worded that may be the cause of confusion; I've never read it to verify. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -Original Message- From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] Sent: Wednesday, March 06, 2002 1:04 PM To: [EMAIL PROTECTED] Subject: Re: certificationZone Bridging White paper ! [7:37393] At 08:34 AM 3/6/02, Phil Barker wrote: Just been re-reading this paper by David Wolfsener. See SNIP below. In the instance where the RII indicator is a 1 the frame will be 'source routed' if the frame is 'source routed' then surely this implies that the RIF must be manipulated in order to reflect the true Source Route The RIF is just referenced (not changed) in frames that are specifically routed. In other words, once the end station has found a route, it just puts it in the frame and the bridges just read it forwards or backwards and route accordingly. Could that be what he's getting at?? On the other hand, I agree with you that on an explorer, an SRT bridge changes the RIF. SRT simply implies a couple things: 1) If the RII is zero, just perform normal Ethernet-style transparent bridging 2) If the RII is one and redundant bridges exits, use the spanning tree to determine which way to forward explorer frames. By the way, SRT is the only form of source route bridging that the IEEE ever standardized. And you can get it for free! ;-) It's in Annex C of IEEE 802.1D, which you can get here: http://standards.ieee.org/getieee802/ Have fun with it! Priscilla !!! I havn't got my 'Interconnections' with me so I cannot confirm. Any ideas ? Phil. SNIP Source Route Transparent Bridging (SRT) SRT works by analyzing the RII bit to determine if a RIF is present. If the RII bit is 0, then a RIF is not present and the frame is transparently bridged. If, however, the RII bit is 1 and a RIF is present, then the frame is source routed. Note that SRT bridges do not add or remove RIFs to frames. By now, you ought to wonder how to configure SRT. END __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=37476t=37393 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
