Browsing Tag
cisco
82 posts
How to Configure BGP Route Filtering on Cisco Routers: Prefix Lists and Route Maps
Filtering is the backbone of safe BGP operation. Every route you accept from a peer, every route you…
How to Implement BGP Route Aggregation on Cisco Routers: Summarization and Optimization
Every additional route in the global BGP table costs memory, CPU, and convergence time — not just for…
How to Configure BGP Authentication on Cisco Routers: MD5 Security Setup Guide
BGP sessions run over plain TCP, and without authentication, anything that can inject or spoof TCP segments toward…
How to Configure OSPF Authentication on Cisco Routers: Type 1, Type 2, and MD5 Security
OSPF forms adjacencies based on hello packets exchanged between routers on a shared segment, and by default, nothing…
How to Set Up EIGRP Authentication on Cisco Routers: MD5 Security Configuration
If there’s one thing I’ve learned from years of running EIGRP in production networks, it’s this: an unauthenticated…
How to Configure Private VLANs (PVLANs) on Cisco Switches: Isolated and Community Ports
Every network engineer eventually runs into a scenario where regular VLANs just aren’t granular enough. Maybe it’s a…
How to Implement Port-Based Authentication (802.1X) on Cisco Switches: Complete Configuration Guide
There’s a specific moment in every network security conversation where someone asks, “so what stops a random laptop…
How to Configure First-Hop Redundancy with GLBP on Cisco Routers: Load Balancing and Failover
I always tell people learning first-hop redundancy protocols that HSRP and VRRP solve half the problem — they…
How to Configure EtherChannel Load Balancing Methods on Cisco Switches: Complete Guide
I’ve lost count of how many times I’ve seen an EtherChannel bundle “working” — both links up, port-channel…
How to Set Up VTP (VLAN Trunking Protocol) Pruning on Cisco Switches for Optimized Traffic
The first time I really understood the value of VTP pruning was watching broadcast traffic from a VLAN…