Hi. I have a question about BGP SoO. what is the need for using this Loop-prevention method in BGP, whereas, I think, the CE router will drop the updates received from PE router due to AS-Path loop prevention method? (for example, refer to http://www.cisco.com/en/US/docs/ios/12_4t/12_4t11/htbgpsoo.html) in this example, CPE1 advertises some prefixes to PE1. whithout using SoO, PE1 will send the vpnv4 routes to PE2 and then, this router advertises the mentioned prefixes to CPE2. will CPE2 drop those prefixes due to AS-Path loop prevention mechanism? (because it will see its own AS# in AS-Path)? if this was true, then what is the need for using SoO on PE routers? if not, why CPE2 will not drop the prefixes due to AS-Path loop prevention? thank u.
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