MP-iBGP (Multi-Protocol iBGP) is used because it has community extensions inherent to the routing protocol, to pass VPN related information among the PE (Provider Edge) routers. Using Extended Communities VPN related information such as, Route Target (RT), Site of Origin (for dual home CEs) as well as VPNv4 information can be passed among iBGP peers. Because this is an iBGP environment, all PEs will receive route updates from everyone else. (You can use route reflectors to lessen the peer statements). The iBGP environment requires that all PEs be in sync (global table). The import statements within the VRF determine which routes to take out of the BGP global table and install into the VRF routing table. The export statements indicate which VRF routes will be exported to your iBGP peers.
You can use an underlying IGP to establish your peers (nothing different than dealing with normal iBGP). OSPF and IS-IS are the most common IGPs as they provide addtional hooks within the IOS code to support additional features such as traffic engineering (examples: support for RSVP, CR-LDP), etc. Ken Sexton Data Network Engineering ICG Communications [EMAIL PROTECTED] -----Original Message----- From: thinkworker [mailto:[EMAIL PROTECTED]] Sent: Thursday, March 21, 2002 3:58 AM To: [EMAIL PROTECTED] Subject: Re[2]: Why we need BGP to establish MPLS? [7:39014] It seems I had to use IBGP to establish MPLS, so can u explain how can we setup a MPLS network without BGP? Or maybe U mean using the static route? I should check the book I've got called "MPLS & VPN Architecture & Implement" of Cisco press (though it is translated very poor) but I had not the book in my hand:( By the way, is the book outdated? On Thu, 21 Mar 2002 03:19:34 -0500 "nrf" wrote: > You don't need BGP to establish MPLS. > > On the other hand, you might need BGP to enable certain 'value-added' MPLS > applications. > > > ""thinkworker"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > Why we need BGP to establish MPLS? > > > > Now we had to use IGP and IBGP to set up MPLS in a AS. It seems quite > > not necessary. > > > > Can anyone help? Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=39037&t=39014 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
