IPv6 over IPv4 tunneling allow access to the IPv6 Internet in absence of an IPv6 native access provider (Or interconnection between any IPv6 islands over an IPv4 infrastructure). Cisco routers support automatic…
Category: CCNA Articles
CCNA Articles
Frame Relay Frequently Asked Questions
In preparation of our CCNP exam, we want to make sure we cover the various concepts that we could see on our Cisco CCNP exam. So to assist you, below we will…
OSPF Convergence
Resiliency and redundancy to circuit failure is provided by the convergence capabilities of OSPF at layer 3. There are two components to OSPF routing convergence: detection of topology changes and recalculation of…
IGP – Default Route Summary
Default route RIP static route 0.0.0.0 to null 0, and the “network 0.0.0.0” command under the RIP process, static route 0.0.0.0 to null 0, and the “redistribute static” command under the RIP…
Frame-Relay – Things to Remember
When “encapsulation frame-relay” command is issued on an interface, the router will learn all the DLCIs associated with that interface via LMI updates. Then once an IP address is configured on the…
BGP – Things to Remember
1. BGP uses TCP port 179 for transport. Router with the higher BGP router-id initiates BGP session from a random port. 2. The interface from which the BGP router ID is taken…
IGP – Things to Remember
1. Routing occurs by finding the longest match in the routing table and by recursing to the outgoing interface. 2. We can debug the transiting traffic by enabling the process switching. But…
EIGRP – Things to Remember
1. The IP header of an EIGRP packet specifies protocol number 88. 2. To establish neighbor relationship, the neighbors must be in the same IP subnet. While EIGRP supports secondary IP addresses…
OSPF – Things to Remember
1. The IP header of an OSPF packet specifies protocol number 89. 2. To establish OSPF neighbor adjacency, hello/dead timers, MTU (otherwise have to use "ip ospf mtu-ignore") must match. Unique router-id…