Cisco IOS permits to define a shortcut to complex command. An alias can be configured to do anything that can be done at the command line, but an alias cannot move between modes, type in passwords, or perform any interactive functions.
To create a command alias, issue the alias command in global configuration mode. The syntax [...]

One of the things that usually are not implemented by the network administrator is the banner; but what and why use it?
The banner is a feature used not only on Cisco systems but also in other systems like Unix, Linux and so on. It permits to define a text that it is displayed in some [...]

In ”An introduction to SNMP” I have explained how SNMP protocol works and how use it; but what are the softwares that use SNMP to monitor network bandwith? HP Openview, Ciscoworks, MRTG are some examples.
In this article I will explain how monitor Cisco Switches/Routers bandwith under a Linux machine using a free open source tool: MRTG.
The Multi Router Traffic [...]

Not everyone knows that HSRP, a fault-tolerant default gateway protocol, has two versions: version 1 (the default) and version two. The second version was integrated from IOS Release 12.2(25)S.
HSRP Version 2 features:

It advertises and learns millisecond timer values. This change ensures stability of the HSRP groups in all cases.
It expands the group number range from 0 to 4095 [...]

The Spanning Tree Protocol is an OSI layer-2 protocol that ensures a loop-free topology for any bridged LAN. Spanning tree allows a network design to include spare (redundant) links to provide automatic backup paths if an active link fails, without the danger of bridge loops, or the need for manual enabling/disabling of these backup links. [...]

Cisco Router and Security Device Manager (SDM) is a Web-based device-management tool for Cisco routers that can improve the productivity of network managers, simplify router deployments, and help troubleshoot complex network and VPN connectivity issues.
Network and security administrators and channel partners can use Cisco SDM for faster and easier deployment of Cisco routers for integrated [...]

Introduced in the Cisco IOS Release 12.2(15), Gateway Load Balancing Protocol (GLBP) is supported by Cisco 1700, 2600, 3620, 3631, 3640, 3660, 3725, 3745, 7100, 7200, 7400, 7500 series. GLBP is a Cisco proprietary protocol that attempts to overcome the limitations of existing redundant router protocols (HSRP, VRRP, …) by adding basic load balancing functionality.
GLBP [...]

The Hot Standby Router Protocol (HSRP) is a Cisco proprietary first-hop redundancy protocol (FHRP) designed to allow for transparent fail-over of the first-hop IP router, and has been described in detail in RFC 2281.
HSRP provides high network availability by providing first-hop routing redundancy for IP hosts on Ethernet, Fiber Distributed Data Interface (FDDI), Bridge-Group Virtual [...]

Cisco IOS permits to define multiple privilege levels for different accounts. This could be useful when many people work on the same router / switch, but with different roles (operator, tecnhician, network manager) and there is no time to implement an authentication server.
There are 16 different privilege levels that can be used. Level 0 is [...]

There are some “standards” steps used for basic configuration on your Cisco router/switch:

Define the hostname
Assign the privileged level
Secure console port
Secure VTY lines
Encrypt the passwords