In the topology Router R3 receives 1.1.1.1/32 route information from R2...
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Routing from scratch… Part 1
The person in A wants to join its colleagues in location B through the network topology described in the below figure. This person needs to go back home at the evening! ” This person...
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Multicast routing: a step by step… Part 1
In the above test lab, Servers send multicast trafic to both clients....
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Routing from scratch… Part 0
The person in A wants to join its colleagues in location B through the network topology described in the below figure. This person needs to go back home at the evening!...
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BGP session keepalive and hold times
At the beginning of the BGP peering establishment, the BGP neighbors agree on the hold time value (included in OPEN message): the time a peering would be maintained without the reception of a KEEPALIVE...
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Vlan propagation and Cisco FabricPath
PC-A and PC-B belong to the same broadcast domain that is defined by vlan X. Without FabricPath (FP), a frame that is sent by PC-A is received by FP-SW1. PC-1 MAC source address is...
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EIGRP over a vNET trunk
New IOS release 15.x introduced Easy Virtual Network (EVN) functionality to leverage some existing deployment features such as VRF-Lite and QinQ. Its ease of configuration is a real advantage. The idea is very simple:...
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VPNv4 BGP AS-Override Feature into play!
AS-Override feature applies to sites that have the same AS number and are linked by another AS number. In BGP, loop prevention would prevent any site from learning other site routes due to the...
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Point-to-Point OSPF Network Operation over a LAN that connects multiple routers
What happens when LAN interfaces are configured as point-to-point network type OSPF interfaces instead of default broadcast type? And more than 2 ospf routers are present on this media? Let’s test this on network...
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DUAL route FSM Processing of EIGRP Queries
An interesting case of how DUAL route FSM operates. First let’s note that an EIGRP router send a Query to its neighbor to find a better route to a destination that has passed from...
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1 Minute
Understand RIP Routing Timers All in One Shot!
Cisco’s RIP implementation defines 4 times tight to one periodic update interval and 3 states: invalid, hold-down and flush. The misleading information is that they are referred to as “timers” in configuration part! Apart...
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