思科的isp运营商内部高级培训教材6.pdf

成都互联神州思科培训 一品阳光 BGP Scaling Techniques ISP/IXP Workshops 专业技术论坛 ISP Workshops © 2001, Cisco Systems, Inc. All rights reserved. 1 成都互联神州思科培训 一品阳光 BGP Scaling Techniques • How to scale iBGP mesh beyond a few peers? • How to implement new policy without causing flaps and route churning? • How to reduce the overhead on the routers? 专业技术论坛 ISP Workshops © 2001, Cisco Systems, Inc. All rights reserved. 2 成都互联神州思科培训 一品阳光 BGP Scaling Techniques • Dynamic reconfiguration • Peer groups • Route flap damping • Route reflectors • (Confederations) 专业技术论坛 ISP Workshops © 2001, Cisco Systems, Inc. All rights reserved. 3 成都互联神州思科培训 一品阳光 Dynamic Reconfiguration Soft Reconfiguration and Route Refresh 专业技术论坛 ISP Workshops © 2001, Cisco Systems, Inc. All rights reserved. 4 成都互联神州思科培训 一品阳光 Soft Reconfiguration Problem: • Hard BGP peer clear required after every policy change because the router does not store prefixes that are denied by a filter • Hard BGP peer clearing consumes CPU and affects connectivity for all networks Solution: • Soft-reconfiguration 专业技术论坛 ISP Workshops © 2001, Cisco Systems, Inc. All rights reserved. 5 成都互联神州思科培训 一品阳光 Soft Recon