Rik, Eeeeeeeeek! Yep I went off on one there. Mouth into overdrive - brain in neutral. I love that embarrassing feeling when you've lost the plot and not realised until it's public viewing material. I think users of a certain age should be provided with a "Delete my drivel" facility, to compensate for senility. Cheers, Gaz ""Rik Guyler"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > I think that what you have described is "multi-layer" switching. > > As Howard has mentioned in past posts, L3S is simply a marketing term as is > wire-speed switching. Layer 3 Switching is simply a line card, typically in > a chassis-based system, that can make routing decisions (layer 3) using > hardware-based technology (layer 2). By not relying on the fundamentally > slow software decision making, this process greatly enhances the speed at > which the decisions are made. > > There are other types of L3S devices, such as a 2948G-L3. This switch uses > ASICs to make routing decisions within hardware. When you purchase one of > these beasts, you basically have a 48-port gigabit router! > > Inter-VLAN routing is just routing. Basically, it can be performed with any > routing-capable device so long as you have the appropriate interfaces. The > difference between Inter-VLAn routing and legacy routing really has nothing > to do with routing at all. The real difference is how the LANs have been > broken out: either Layer 2 (VLANs) or Layer 3 (IP subnetting). > > If you know something about routing, then you know something about > Inter-VLAN routing. Read up on VLANs (I suggest the Kenndy Clark CCIE > switching book) and all will become clear. > > Rik > > -----Original Message----- > From: Gareth Hinton [mailto:[EMAIL PROTECTED]] > Sent: Monday, May 28, 2001 6:09 AM > To: [EMAIL PROTECTED] > Subject: Re: What do "interVLAN routing "and" Layer 3 switching " mean > [7:6104] > > > Hi Frank, > > I think the best description for Layer 3 Switching is "Route once - Switch > many". > The first time a packet in a particular "flow" passes through, a routing > function will be used (on a different card, or even in a different device). > But to speed up the processing of any further packets in that flow, a cache > is created in the switch to remember this flow. The next time a packet comes > through which matches this flow it will be switched without using the router > functionality, therefore speeding things up. > The definition of a flow can differ depending on configuration. For > instance, normally a flow may be any packet to a particular destination, but > if , for example, an extended access list is configured, the criteria for > the flow may tighten up i.e. to be considered part of a flow, the source and > destination are compared. > Inter-VLAN routing means a packet gets routed every time. > > Regards, > > Gaz > > > > > ""frank"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > What does the following mean ?it's cut from a description of WS-X4232-L3 > on > > cisco website. > > > > > > The Catalyst 4003 and 4006 Layer 3 Services module provides interVLAN > > routing for the Catalyst 4000 family switch and provides Layer 3 switching > > between the Gigabit Ethernet interfaces. > > > > "John Hardman" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > Hi > > > > > > OK I'll bite... > > > > > > Yes there is a difference. It gets a little convoluted, but there is a > > > difference. > > > > > > L3 switching: Think of a L3 switch as a multi port router that operates > at > > > wire speed. The 2948G-L3 is an example. It is just a 50 port Ethernet > > > router. So L3 switching is routing traffic at wire speeds. You could use > > one > > > of these to route between VLANs, or route between networks. > > > > > > Inter-VLAN routing: This is a technique, technology that is only used to > > > route traffic from one VLAN to other VLAN(s). It generally takes place > at > > > wire speeds inside a Cat switch with a L3 switch option, but is often > see > > > with routers that do not work at wire speeds. > > > > > > So the bottom line... think of a L3 switch as a device, and Inter-VLAN > > > routing as a technology. > > > > > > HTH > > > -- > > > John Hardman CCNP MCSE > > > > > > > > > ""frank"" wrote in message > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > Any difference? > > > > > > > > "frank" wrote in message > > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > > Thanks, > > > > > > > > > > > > > > > Frank > > > > > FAQ, list archives, and subscription info: > > > > http://www.groupstudy.com/list/cisco.html > > > > > Report misconduct and Nondisclosure violations to > [EMAIL PROTECTED] > > > > FAQ, list archives, and subscription info: > > > http://www.groupstudy.com/list/cisco.html > > > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > FAQ, list archives, and subscription info: > > http://www.groupstudy.com/list/cisco.html > > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=6144&t=6144 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
