Rapid Spanning Tree (RSTP)

RSTP (802.1w) Rapid Spanning Tree Protocol RSTP is backward compatible with classic STP (802.1d) RSTP has faster convergence than STP. Introduces new simplified Port States and Port Roles. The Timers in RSTP are replaced on a Synchronization Process which is also called as the Proposal and Agreement Process....
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Few notes on Spanning Tree Operations

Default Behavior in STP (802.1D) In Spanning Tree Protocol, the first step is to choose a root bridge for a vlan. Root Election is  Based on Bridge Priority the tie breaker is Mac address when the Bridge Priority on both the switches is equal. In PVST the ext-sys-id...
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IP Multicast Overview

IP Multicast A short High-Level Overview Source of Multicast generates a single data feed for all interested parties and sends the feed to a  destination multicast address which is also known as a multicast group address. All interested parties will be listening for the data on this multicast...
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Basic MPLS VPN Configuration

The network topology  is  a very simple MPLS VPN configuration for two customers using overlapping address space and each customer has 2 sites connecting to the Provider network. R1,R2 and R3 are the provider routers, R1 being the P-Router and R2,R3 PE-Routers. Customer-1 is using BGP to connect...
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MPLS VPN Overview

The MPLS VPN backbone and the customer sites exchange layer-3 customer routing information and packets are forwarded between multiple customer sites through the MPLS enabled backbone using the MPLS VPN services. Components of MPLS VPN 1. Customer networks: under customer’s administrative domain 2. Provider network: Under Provider’s admin...
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