Table Of Contents
Cisco IOS Login Enhancements (Login Block)
The Cisco IOS Login Enhancements (Login Block) feature provides a way for you to better secure your Cisco IOS software-based device against possible malicious connection attempts.
The login block and login delay options introduced by this feature can be configured for Telnet, SSH, or HTTP*1 virtual connections. By enabling this feature, you can slow down "dictionary attacks" by enforcing a "quiet period" if multiple failed connection attempts are detected, thereby protecting the routing device from a type of denial-of-service attack.
Documentation for the "Cisco IOS Login Enhancements (Login Block)" feature has been moved to another document.
Configuration information is included in the "Cisco IOS Login Enhancements (Login Block)" documentation module of the Cisco IOS Security Configuration Guide: Securing User Services, Release 12.4T, at the following URL:
Command Reference Information
The following commands were introduced with or modified by this feature:
•login quiet-mode access-class
•See also the security authentication failure rate command (introduced as part of the "AutoSecure" feature).
For command reference documentation of these commands, see the Cisco IOS Security Command Reference appropriate to your software release. For example, for command reference documentation for Cisco IOS software release version 12.2(33)SXH, see the Cisco IOS Security Command Reference, Release 12.2SX at
Master Commands Lists
Cisco IOS master commands lists provide an alphabetical list of all Cisco IOS commands in a Cisco IOS release.
Cisco IOS new, modified, removed, and replaced commands lists provide an alphabetized list of all new, modified, removed, and replaced commands in a Cisco IOS release.
Cisco IOS Master Commands List, Release 12.2SB, at the following URL:
Cisco IOS New, Modified, Removed, and Replaced Commands List, Release 12.4T, at the following URL:
Document ID: gt_login
First Published: 11/03/2003
Last Modified: 08/23/2007 (Revision 18)
Applies to: Cisco IOS Software Releases 12.3T, 12.4, 12.1E, 12.2S, 12.2SB, 12.2SR, 12.2SX, and all derivative releases.
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
© 2003-2007 Cisco Systems, Inc. All rights reserved.1 *HTTP login block and login delay support is in releases 12.2(33)SXH and 12.4(16)T and later.