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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At the begining, … it was not DMVPN!
The simplest way to interconnect 3 or more routers in the same broadcast domain (and the same subnet) is by attaching them to a switch (or hub) in the same vlan....
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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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Transmit Power Control in IEEE 802.11 Cisco WLAN networks
TPC stands for Transmit Power Control. It’s a one of Cisco RRM, Radio Resources Management, techniques that are aimed at tackling interference, cross and co-channel, in Wlan networks....
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