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List of articles – newest first:

• I just passed the AWS Advanced Networking Specialty January 8, 2026
• Cisco Champion 8th year in a row April 9, 2025
• Google Jupiter Data Center Network Fabric – New Way of Building Data Center Network Underlay September 17, 2022
• Cisco DNA Upgrade Issues – Application Update Stuck June 8, 2022
• Cisco Catalyst Stack Upgrade May 8, 2022
• TOP 25 in Cisco IT Blog Awards March 15, 2022
• Switch vSphere Enterprise Plus license to vSphere Standard on a NSX-T enabled cluster December 15, 2021
• Missing good old ‘wr’ command on N9K? let’s bring it back! October 15, 2021
• NSX-T Edge Transport Node Packet Capture September 30, 2021
• VMware NSX-T Install Tips & Tricks December 23, 2020
• VMware TKGI – Deployment of Harbor Container Registry fails with error December 11, 2020
• New ACI deployment? Watch out when connecting APICs to Leafs September 27, 2020
• Software-defined data center and what’s the way to do it February 10, 2020
• Cisco Champion for 2020 February 4, 2020
• Best Analysis Finalist – Cisco IT Blog Awards for 2019 November 25, 2019
• Cisco ACI – API Calls vs JSON POST September 24, 2019
• Cisco ACI – Configuring by POSTing JSON September 23, 2019
• Juniper SRX Cluster Failover Tuning August 27, 2019
• Configuring MACsec Encryption July 11, 2019
• How to Advertise a Route from ACI Layer2 BD Outside the Fabric? April 17, 2019
• ACI MultiPod – Enable Standby APIC April 8, 2019
• Setting up Cisco ACI From Scratch March 12, 2019
• ACI MultiPod and how to build MultiDatacenter with Cisco ACI February 28, 2019
• What is Cisco ACI? January 13, 2019
• CLOS Topology January 11, 2019
• Cisco Champion for 2019 January 3, 2019
• BFD – Sub-second Failure Detection September 11, 2018
• MTU and TCP MSS June 29, 2018
• The New Way of Generating IPv6 – SLAAC EUI-64 Address Format March 22, 2018
• Create or Edit a File on Cisco IOS Flash March 1, 2018
• I Became Cisco Champion for 2018 January 19, 2018
• Link Aggregation – LACP Protocol January 5, 2018
• Check Point Firewall VM Disk Resize November 29, 2017
• Celebrating 6 Years November 29, 2017
• IPv6 Generated with EUI-64 Has a Strange Bit Inside October 30, 2017
• MACSec – Media Access Control Security August 31, 2017
• Reflexive Access List May 12, 2017
• Books that I like May 3, 2017
• Juniper Control Plane Protection May 3, 2017
• How to Clear Entire Configuration of your Juniper Device April 13, 2017
• You Know How Networks Work, Want To Know How Everything Else Works? Here’s Some Books March 16, 2017
• The Use of Graph Database in Network Complexity Analysis February 24, 2017
• Redistribute Static on Juniper & Cisco February 22, 2017
• Enable Source-Specific Multicast in Iperf December 30, 2016
• Source-Specific Multicast Configuration December 29, 2016
• QKD – How Quantum Cryptography Key Distribution Works December 1, 2016
• Unable to access Cisco ASA through AnyConnect VPN? November 13, 2016
• Introduction to Quantum Cryptography November 11, 2016
• Cryptography November 2, 2016
• ICANN and the future of DNS and internet October 12, 2016
• ISSU Upgrade of Cisco Catalyst 6880-X VSS Cluster and 6800ia FEX extenders September 10, 2016
• Cisco Catalyst 6880-X VSS ISSU Upgrade Steps September 10, 2016
• Juniper vMX Lab Setup on VMware August 10, 2016
• Juniper vMX Multicast Configuration August 3, 2016
• WoL – Wake On LAN June 2, 2016
• Network Virtualization May 13, 2016
• TFTP via VRF April 1, 2016
• VRF – Virtual Routing and Forwarding March 26, 2016
• Static Route Load Balance December 22, 2015
• What is route recursion December 7, 2015
• Control Plane Protection in Cisco IOS October 7, 2015
• How Encryption of Network Traffic Works? September 25, 2015
• Nagle’s algorithm August 27, 2015
• Proxy ARP August 6, 2015
• Mitigate DoS Attack using TCP Intercept on Cisco Router July 29, 2015
• How to generate network packets – Ostinato Packet/Traffic Generator June 22, 2015
• SDN SOFTWARE DEFINED NETWORKS: AN OVERVIEW June 12, 2015
• How to Enable Dot1x – more complex setup for wired network June 7, 2015
• How to Enable Dot1x authentication for wired clients June 6, 2015
• Why numbering should start at zero? April 30, 2015
• What is a non-blocking switch? April 25, 2015
• HOL Head-of-line blocking April 21, 2015
• TCAM and CAM memory usage inside networking devices February 25, 2015
• Solicited-node multicast address February 22, 2015
• How can router decide so fast? January 16, 2015
• I became CCIE# 46173 January 10, 2015
• Cisco VIRL is finally out December 2, 2014
• INE v5 Full-Scale Practice Lab1 TS GNS3 topology October 24, 2014
• When they throw a Cisco guy to do something with HP networking gear October 15, 2014
• INE R&Sv5 Workbook Full-Scale Practice Lab1 made in GNS3 October 7, 2014
• What is the difference between tunnel | transport mode in IPsec September 23, 2014
• /31 subnet in point-to-point links. Is that possible? June 5, 2014
• BGP dampening – punishment for unstable BGP prefixes May 23, 2014
• Source-based routing in IPv4 and IPv6 networks May 3, 2014
• BGP communities April 17, 2014
• VXLAN – Virtual Extensible LAN April 14, 2014
• Redundant Default Gateway solutions in IPv4 networks February 21, 2014
• ICMP – Internet Control Message Protocol February 21, 2014
• IPv6 Anycast Address type January 13, 2014
• Troubleshooting EIGRP Neighbor Relationships December 3, 2013
• Packet capture in Cisco IOS November 8, 2013
• CCIE RS v5 blueprint will be announced this month? November 2, 2013
• GNS3 topology for INE Workbook October 30, 2013
• Forwarding UDP broadcast traffic mechanisms October 24, 2013
• IPv6 First-Hop Security September 26, 2013
• MPTCP – Multipath TCP September 25, 2013
• Administrative Distance for Static Route is 1 or 0? August 28, 2013
• Difference between defining static routes with next-hop address or exit interface August 28, 2013
• IPv6 Implementation beyond theory & How playing with RA messages may be issue-istic August 21, 2013
• Cisco VIRL – Virtual Internet Routing Lab August 12, 2013
• IPv6 RA Router Advertisement and all the flags inside July 22, 2013
• CCIE R&S v5 blueprint announcement? June 20, 2013
• DCCP – Datagram Congestion Control Protocol June 12, 2013
• Don’t use 192.168.1.0/24 on work LAN June 5, 2013
• What is static floating route May 7, 2013
• What is Jitter in Networking? May 3, 2013
• What’s that % sign after ipconfig IPv6 address? March 14, 2013
• RADIUS server Infrastructure March 13, 2013
• IPv6 – SLAAC Stateless Address Autoconfiguration March 11, 2013
• PBR – Policy-based Routing configuration example February 19, 2013
• PBR – Policy Based Routing using Route map February 8, 2013
• Proxy and Reverse Proxy Server February 5, 2013
• Wildcard mask – What’s the difference from subnet mask? January 23, 2013
• When I connect to device with telnet or SSH I don’t see logging? January 10, 2013
• IPv6 – SLAAC EUI-64 Address Format January 7, 2013
• L2TP – Layer 2 Tunneling Protocol January 2, 2013
• NDP – Neighbor Discovery Protocol December 31, 2012
• PNRP Name Resolution – How it works? December 28, 2012
• PNRP the New DNS – Peer Name Resolution Protocol December 27, 2012
• COGNITIVE NETWORKS THE NETWORKS OF THE FUTURE December 3, 2012
• Find unknown static IP on device November 30, 2012
• SAP – Session Announcement Protocol November 25, 2012
• Recovery From Corrupt or Missing Software Image on Cisco device November 16, 2012
• Unidirectional communication filter between two VLANs November 4, 2012
• NetBIOS October 22, 2012
• How to prevent or stop DoS attacks? October 16, 2012
• DoS Methods – PDoS, Permanent DoS attacks October 12, 2012
• MPLS – Multiprotocol Label Switching October 10, 2012
• DoS Methods – ICMP and SYN flood, Teardrop and Low-rate DoS attacks October 9, 2012
• DDoS – Distributed Denial of Service attack October 3, 2012
• DoS and DDoS – Denial of Service attacks October 1, 2012
• Routing between VLANs September 26, 2012
• Trunking Methods – VLAN Identification methods across multiple switches September 19, 2012
• ISL Inter-Switch Link Protocol – Trunking or Frame Tagging protocol September 19, 2012
• VLANs – Trunk and Access link types September 17, 2012
• Static vs Dynamic VLANs September 13, 2012
• VLAN – What are VLANs? September 11, 2012
• VLAN Security – Main VLAN reason September 10, 2012
• VLANs controling broadcast propagation September 6, 2012
• Why we need VLANs, an Introduction to VLAN technology September 5, 2012
• IPSec August 10, 2012
• Application Layer Firewalls August 9, 2012
• Pathping more than handy network troubleshooting tool August 2, 2012
• Transparent Firewalls July 22, 2012
• How does Firewall defend our Network? July 22, 2012
• MIME – Multipurpose Internet Mail Extensions July 2, 2012
• Protecting a VoIP Network with Security Appliances June 27, 2012
• Implement Auxiliary VLANs to make VoIP Networks secure June 23, 2012
• Make voice Network more secure June 21, 2012
• Cisco EnergyWise – New way to save energy June 16, 2012
• Voice protocols – VoIP protocols June 13, 2012
• VoIP Network Components June 11, 2012
• VoIP and IP telephony – Defining Basics of Voice June 8, 2012
• IPv6 Day – 6 June 2012. June 6, 2012
• Flame Virus June 2, 2012
• Vishing and Toll Fraud – VoIP Vulnerability June 1, 2012
• Attack on SIP protocol – VoIP Vulnerability June 1, 2012
• VoIP spam – VoIP Vulnerability June 1, 2012
• VoIP Security – Main Targets of VoIP Attacks May 27, 2012
• BGP – Border Gateway Protocol May 24, 2012
• DHCP – Dynamic Host Configuration Protocol May 17, 2012
• Saving Router Configuration to Server May 9, 2012
• FTP – File Transfer Protocol May 3, 2012
• Use TFTP to configure a Router April 28, 2012
• Gopher April 15, 2012
• Administrative distance – Which route is the best? April 12, 2012
• Difference between Routed and Routing Protocols April 11, 2012
• IMAP – Internet Message Access Protocol April 9, 2012
• Saving VLAN.dat To NVRam April 5, 2012
• IRC – Internet Relay Chat Protocol March 31, 2012
• Firewall – Defending Networks March 29, 2012
• Secure the switch – best steps March 19, 2012
• LDAP – Lightweight Directory Access Protocol March 17, 2012
• PVLAN configuration March 15, 2012
• PVLAN – Private VLANs March 14, 2012
• Netconf March 11, 2012
• VACL – VLAN Access Lists March 6, 2012
• SPAN – Switched Port Analyzer technology and configuration February 28, 2012
• Prevent ARP Spoofing using Dynamic ARP Inspection – DAI February 23, 2012
• Spoofing Attacks – ARP Spoofing February 22, 2012
• Prevent DHCP Server Spoofing by using DHCP snooping February 21, 2012
• Network – Computer network February 20, 2012
• Routers hardware – How are the Routers made? February 17, 2012
• Routing – How are routers working? February 15, 2012
• NNTP – Network News Transfer Protocol February 14, 2012
• Router – What is a router? February 12, 2012
• NTP – Network Time Protocol February 10, 2012
• POP – Post Office Protocol February 7, 2012
• Configuring LLDP – Link Layer Discovery Protocol February 5, 2012
• LLDP – Link Layer Discovery Protocol February 4, 2012
• What is PIPA – Protect Intellectual Property Act February 4, 2012
• How to configure CDP – Cisco Discovery Protocol February 3, 2012
• RPC – Remote Procedure Call January 30, 2012
• RTP – Real-time Transport Protocol January 28, 2012
• What is SOPA – Stop Online Piracy Act January 26, 2012
• About Juniper – What is Juniper exactly January 23, 2012
• CDP – Cisco Discovery Protocol January 20, 2012
• Protecting Against STP Layer 2 Attack January 19, 2012
• STP Layer 2 attack – Manipulating Spanning Tree Protocol settings January 17, 2012
• Mitigate VLAN hopping attack – Get rid of Layer 2 attacks January 16, 2012
• VLAN hopping attack – Switch Spoofing and Double tagging January 16, 2012
• Manage Router’s ARP Cache January 15, 2012
• Creating Command Aliases – Be faster in IOS typing January 14, 2012
• Port Numbers – How does Transport layer identifies the Conversations January 13, 2012
• TCP and UDP port numbers – complete list January 12, 2012
• SMPP – Short Message Peer-to-Peer January 11, 2012
• SIP – Session Initiation Protocol January 9, 2012
• Dynamic Routing Protocols January 8, 2012
• Routing – Static and Dynamic routes – What is route? January 5, 2012
• Network Downtime Is Expensive – Time is Money January 2, 2012
• Using Port Security to Mitigate Layer 2 Attacks January 2, 2012
• XMPP – Extensible Messaging & Presence Protocol December 30, 2011
• SSI – Simple Sensor Interface protocol December 26, 2011
• SPDY – reducing web page load time protocol December 22, 2011
• Cisco Switch password recovery – Catalyst Fixed Configuration Switches December 20, 2011
• Optical Fiber – Fiber Optics December 19, 2011
• Telnet Attacks – Ways to compromise remote connection December 17, 2011
• CDP Attacks – Cisco Discovery Protocol Attack December 16, 2011
• Spoofing Attacks – DHCP Server Spoofing December 15, 2011
• MAC Address Flooding – MAC address table overflow attacks December 14, 2011
• Switch Security Attacks – Layer 2 Security December 14, 2011
• About Cisco – What is Cisco exactly December 11, 2011
• About Cisco IOS and Juniper JUNOS December 9, 2011
• OSI model – Get to know networking with 7 layer model December 4, 2011
• Automatic router backup to FTP server – How to configure? December 1, 2011
• Telnet and SSH – Remotely connect to device using Telnet and SSH November 28, 2011
• SMTP – Simple Mail Transfer Protocol November 27, 2011
• Command Modes – Cisco IOS – Juniper Junos November 24, 2011
• UTP Cables – Unshielded Twisted Pair Cable November 23, 2011
• Switch & Hub – What are they and what is the difference? November 18, 2011
• Collisions and collision detection – What are collisions in Ethernet? November 16, 2011
• Data Packet – IP Packet – What is this packet story all about? November 14, 2011
• NIC – Network Interface Card November 13, 2011
• Host – When the Host is Client and when Server? November 10, 2011
• MAC address (MAC L2 addressing) – What is this physical addressing? November 9, 2011
• WAN – Wide Area Network November 6, 2011
• Basic Cisco and Juniper router Configuration November 4, 2011
• What is my IP address November 4, 2011
• IP Address – Internet Protocol address: Basic about IPv4 November 2, 2011
• DNS – Domain Name System October 30, 2011
• UDP – User Datagram Protocol October 27, 2011
• Backbone – What is backbone? October 24, 2011
• VPN – What is VPN and how it works? October 20, 2011
• Phishing – What is phishing? October 18, 2011
• TCP – Transmission Control Protocol October 17, 2011
• HTTP – Hypertext Transfer Protocol – What is HTTP Protocol used for? October 12, 2011
• Server – What is a server and how it works? October 9, 2011
• LAN – Local Area Network October 7, 2011
• Network Fundamentals – Our main goal October 6, 2011
• Network – More news about way it works October 6, 2011
• Network – What is network exactly? October 4, 2011
• How We Open a Web Page and What is Going on Behind? October 2, 2011
• IPv6 addresses – What is IPv6? October 1, 2011
• What is a protocol? September 30, 2011
• What is internet – How does the internet work and why is so important? September 29, 2011