RE: Collapsed Backbone [7:41418]
First of all thanks to Tom , Georg ,Howard and every body. To be honest me too is surprising with these terms, anyhow these terms simplify how to remember the scenarios and all the staff arround, I do not know the essential reason with giving such a name but i think collapsed backbone has given this name because the network confined with one building, there is only one switch block ! as the core and distribution layer combined in one device. If I am wrong then please correct me. -Original Message- From: Howard C. Berkowitz [mailto:[EMAIL PROTECTED]] Sent: Monday, April 15, 2002 1:06 AM To: [EMAIL PROTECTED] Subject: RE: Collapsed Backbone [7:41418] First, I wonder who comes up with these terms? Collapsed backbone sounds like something that needs the immediate attention of an orthopedist or chiropractor, while router on a stick sounds like something from the Autobiography of Vlad the Impaler. At 3:49 AM -0400 4/14/02, Georg Pauwen wrote: Hi Ismail, here is what I found on CCO: %A collapsed backbone has high-bandwidth uplinks from all segments and subnetworks to a single device, such as a Gigabit switch, which serves as a ^^^ First key point. The backbone or core device is defined by topology rather than product line. That point being made, it is true that Cisco does position products for access, distribution, and core applications generally based on the requirements of large enterprises. But a core switch could be quite slow and small, if everything else in the network is small and slow, yet still be a reasonable design approach. single point for monitoring and controlling the network%. Second point: as defined, it's also a single point of failure. With a campus network large enough to justify a gigabit switch in a core, this is a bad idea. It's usually better to plan on at least two physical switches that normally loadshare (e.g., switch 1 is the primary for odd-numbered VLANs and switch 2 is the primary for even-numbered), but either can take over the entire load. The following link contains a figure detailing the collapsed backbone design using a Cat4908G-L3: http://www.cisco.com/univercd/cc/td/doc/product/lan/c2900xl/29_35wc/sc/swgo ver.htm Regards, Georg -- What Problem are you trying to solve? ***send Cisco questions to the list, so all can benefit -- not directly to me*** Howard C. Berkowitz [EMAIL PROTECTED] Chief Technology Officer, GettLab/Gett Communications http://www.gettlabs.com Technical Director, CertificationZone.com http://www.certificationzone.com retired Certified Cisco Systems Instructor (CID) #93005 Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=41466t=41418 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Collapsed Backbone [7:41418]
Hi Ismail, here is what I found on CCO: ´A collapsed backbone has high-bandwidth uplinks from all segments and subnetworks to a single device, such as a Gigabit switch, which serves as a single point for monitoring and controlling the network´. The following link contains a figure detailing the collapsed backbone design using a Cat4908G-L3: http://www.cisco.com/univercd/cc/td/doc/product/lan/c2900xl/29_35wc/sc/swgover.htm Regards, Georg Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=41419t=41418 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Collapsed Backbone [7:41418]
First, I wonder who comes up with these terms? Collapsed backbone sounds like something that needs the immediate attention of an orthopedist or chiropractor, while router on a stick sounds like something from the Autobiography of Vlad the Impaler. At 3:49 AM -0400 4/14/02, Georg Pauwen wrote: Hi Ismail, here is what I found on CCO: %A collapsed backbone has high-bandwidth uplinks from all segments and subnetworks to a single device, such as a Gigabit switch, which serves as a ^^^ First key point. The backbone or core device is defined by topology rather than product line. That point being made, it is true that Cisco does position products for access, distribution, and core applications generally based on the requirements of large enterprises. But a core switch could be quite slow and small, if everything else in the network is small and slow, yet still be a reasonable design approach. single point for monitoring and controlling the network%. Second point: as defined, it's also a single point of failure. With a campus network large enough to justify a gigabit switch in a core, this is a bad idea. It's usually better to plan on at least two physical switches that normally loadshare (e.g., switch 1 is the primary for odd-numbered VLANs and switch 2 is the primary for even-numbered), but either can take over the entire load. The following link contains a figure detailing the collapsed backbone design using a Cat4908G-L3: http://www.cisco.com/univercd/cc/td/doc/product/lan/c2900xl/29_35wc/sc/swgover.htm Regards, Georg -- What Problem are you trying to solve? ***send Cisco questions to the list, so all can benefit -- not directly to me*** Howard C. Berkowitz [EMAIL PROTECTED] Chief Technology Officer, GettLab/Gett Communications http://www.gettlabs.com Technical Director, CertificationZone.com http://www.certificationzone.com retired Certified Cisco Systems Instructor (CID) #93005 Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=41427t=41418 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Collapsed Backbone [7:41418]
Georg Pauwen wrote: 4A collapsed backbone has high-bandwidth uplinks from all segments and subnetworks to a single device, such as a Gigabit switch, which serves as a single point for monitoring and controlling the network4. The following link contains a figure detailing the collapsed backbone design using a Cat4908G-L3: http://www.cisco.com/univercd/cc/td/doc/product/lan/c2900xl/29_35wc/sc/swgover.htm Another way to look at collapsed backbones is to consider why it's called collapsed. Cisco uses a hierarchical campus model that scales down to small one-room networks and up to enterprise-wide networks that include multiple buildings. The full model has three tiers or layers (access, distribution, core) and multiple types of building blocks (switch block, core block, server block, mainframe block, WAN block). I don't have statistics but I've seen a lot more collapsed networks than networks that fit the full 3-tiered multi-block multi-building campus model. The collapsed model is very popular and can scale up to hundreds of endsystems and dozens of workgroups (VLANs). All you need is a high-end switch, gigabit cabling (preferably fiber but cat 5e/6 works just fine if you keep the cable lengths in the 90m range and if you don't have EMI to worry about), and a high-end router to serve as a firewall and gateway to the outside. Some of the endsystems can be home-run directly back to the main switch, or they can be aggregated at active or passive consolidation points. The router can be a standalone or can be included in the same chassis as the main switch such as a route service module or layer 3 services module. Cheers, -- TT Message Posted at: http://www.groupstudy.com/form/read.php?f=7i=41422t=41418 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
