Cisco 200-301: IPv4 Subnetting Without Guesswork
IPv4 subnetting becomes difficult when it is treated as a collection of shortcuts instead of a repeatable calculation. Every subnet question is fundamentally…
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Networking.
Routing, switching, wireless networks, network architecture and services.
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Cisco 200-301: First Hop Redundancy with HSRP
A default gateway is a single logical address in a host configuration, but enterprise networks should not make that gateway depend on one…
Read articleCisco 200-301: EtherChannel with LACP and PAgP
EtherChannel combines multiple physical Ethernet links into one logical port-channel so switches can increase bandwidth and preserve redundancy without allowing Spanning Tree Protocol…
Read articleCisco 200-301: DNS, NTP, and Syslog in Cisco Networks
DNS, NTP, and syslog are easy to treat as background services because none of them forwards user traffic. In practice, they shape how…
Read articleCisco 200-301: DHCP Relay and IP Helper Addresses
DHCP works naturally when the client and server share a broadcast domain, but enterprise networks rarely place a DHCP server in every user…
Read articleAWS ANS-C01: Transit Gateway Routing at Scale
AWS Transit Gateway simplifies multi-VPC and hybrid connectivity by replacing many point-to-point links with a hub, but the routing model becomes more important…
Read articleAWS ANS-C01: BGP Design for AWS Direct Connect
AWS Direct Connect gives an organization a dedicated path into AWS, but Border Gateway Protocol determines whether that path behaves the way the…
Read articleAWS SAA-C03: Route 53 Routing Policies and Failover
Amazon Route 53 is often introduced as managed DNS, but architecture decisions begin after the zone exists. The important question is how DNS…
Read articleAWS SAA-C03: NAT Gateway vs NAT Instance in Modern AWS
NAT remains a common part of AWS IPv4 architectures because private workloads often need outbound access to software repositories, partner APIs, or the…
Read articleAWS SAP-C02: Hybrid DNS with Route 53 Resolver
Hybrid DNS becomes an architecture problem as soon as workloads in AWS need to resolve private names hosted on premises while corporate clients…
Read articleMicrosoft AZ-104: Azure Private Endpoints and Private DNS
Azure Private Endpoint changes the network path to a platform service by placing a private IP address from your virtual network on the…
Read articleLPI 201-450: Linux Networking and Routing
Linux networking is a system-administration discipline that combines interface configuration, address management, routing, name resolution, diagnostics, and service behavior. The current LPI LPIC-2…
Read articleISC2 CISSP: Network Security Architecture
Network security architecture defines how users, devices, workloads, applications, management planes, and external partners communicate while limiting exposure and preserving visibility. Modern enterprise…
Read articleRed Hat EX200: Firewalld and Network Security in RHEL
Red Hat Enterprise Linux uses firewalld as the standard high-level firewall management service in many installations. For administrators, the important skill is not…
Read articleCNCF KCSA: Network Policies for Kubernetes Workloads
Kubernetes makes it easy for applications to discover and reach one another, but default connectivity is often broader than a security-conscious production design…
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