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Tuesday, June 16, 2009

Netmask Quick Reference Chart

There are plenty of these netmask references out there, but I prefer my own: hence this Tech Tip. We've never seen anybody use a network larger than a /4 (256M hosts), so we've truncated the table at that point.

Netmask Quick Reference
# bits # hosts Usable
netmask Cisco mask
/4 268435456 268435454
/5 134217728 134217726
/6 67108864 67108862
/7 33554432 33554430
/8 16777216 16777214 class A network
/9 8388608 8388606
/10 4194304 4194302
/11 2097152 2097150
/12 1048576 1048574
/13 524288 524286
/14 262144 262142
/15 131072 131070
/16 65536 65534 class B network
/17 32768 32766
/18 16384 16382
/19 8192 8190
/20 4096 4094
/21 2048 2046
/22 1024 1022
/23 512 510
/24 256 254 class C network
/25 128 126
/26 64 62
/27 32 31
/28 16 14
/29 8 6
/30 4 2
/31 point to point links only
/32 1 1 single IP address use host notation

What's a netmask?

All devices on a local network have a unique IP address, but each address is inherently divided into two parts, a shared network part, and a unique host part, and this information is used by the TCP/IP stack for routing. When sending traffic to a machine with a different network part, it must be sent through a router for final delivery.

The dividing line between the network and host parts is determined by the subnet mask, and it's often seen in notation. It looks like an IP address, and it uses a "1" bit to select, or "mask" the network part.

[IP address with mask]

In this case, the netmask of represents 29 bits of network and 3 bits of host (totalling 32 bits, of course), and this give 8 possible IP addresses in this range. The first and last of the range are reserved addresses, giving 6 usable addresses that may be assigned to a device. zero broadcast available available available available available available ones broadcast

Thursday, April 9, 2009

Troubleshooting Linux(R) Firewalls

While Linux firewalls are inexpensive and quite reliable, they lack the supportcomponent of their commerical counterparts. As a result, most users of Linuxfirewalls have to resort to mailing lists to solve their problems. Our authorshave scoured firewall mailing lists and have compiled a list of the most oftenencountered problems in Linux firewalling. This book takes a Chilton's manualdiagnostic approach to solving these problems.The book begins by presenting the two most common Linux firewallconfigurations and demonstrates how to implement these configurations in animperfect network environment, not in an ideal one. Then, the authors proceedto present a methodology for analyzing each problem at various network levels:cabling, hardware components, protocols, services, and applications. Theauthors include diagnostic scripts which the readers can use to analyze andsolve their particular Linux firewall problems. The reference distributions areRed Hat and SuSE (for international market)

Linux Firewalls: Attack Detection and Response with iptables

  • AUTHOR: by Michael Rash
  • Publisher: No Starch Press; 15 September, 2007
  • ISBN: 1593271417
Book Description
System administrators need to stay ahead of new security vulnerabilities that leave their networks exposed every day. A firewall and an intrusion detection systems (IDS) are two important weapons in that fight, enabling you to proactively deny access and monitor network traffic for signs of an attack. Linux Firewalls discusses the technical details of the iptables firewall and the Netfilter framework that are built into the Linux kernel, and it explains how they provide strong filtering, Network Address Translation (NAT), state tracking, and application layer inspection capabilities that rival many commercial tools. You


Transcender Cisco CertificationTranscender Cisco Certification Exam Collection

NOTE: Please do not share this links on any other forums/websites or report them on rapidshare.... Things like these are hard to get and if they get reported and deleted ... I will not upload them again cause it takes a long time and secondly... many people will loose out on good content.

Password is mentioned as part of folder name

Cisco CCNA Actual test

800 great Cisco CCNA 640-802 Exam Questions - Actual test - Latest Update


20 English-learning ebooks

Dictionary Cambridge English Grammar - Check Your Vocabulary for IELTS.pdf
American Accent Training.pdf
Cambridge - English Vocabulary in Use - Elem.pdf
Cambridge - English Vocabulary in Use - Pre-int_Int.pdf
Cambridge - English Vocabulary in Use - Upp_Adv.pdf
Essential Grammar in Use Supplementary Exercises.pdf
Jossey-Bass - English Brainstormers - Ready-to-Use Games and Activities that Make Language Skills Fun to Learn.pdf
New Grammar Practice pre-int with key.pdf
NTC's American Idioms Dictionary.pdf
Speak English Like An American.pdf
The A-Z of Correct English Common Errors in English.pdf
wEBSTER Essential vocabulary.pdf
Word Formation In English.pdf


Learning with English Connection: (BBC) 9

3 levels: Beginner, Intermediate and Advanced. (Each level has 3 CD).
It is a software that teaches you English by listening and watching.
Each course is built in the following steps:
Rapid English
How to say and speak (giving advice, order, opinion…).
Role Play (Practice)
The CD Number 9 is the famous software “ PRONUNCIATION POWER” I have found it in the same collection

CD 1 :

CD 2 :

CD 3 :

CD 4 :

CD 5 :


CD 6 :

CD 7 :

CD 8 :

CD 9 :

Learning to learn English cambridge university

This exciting new package provides a systematic course that enables students to become more effective learners and take on greater responsibility for their own learning. The Learner's Book is divided into two stages. Stage 1 contains activities that focus on styles, needs, organization, and motivation. Stage 2 covers various skills that include: extending vocabulary, dealing with grammar, listening, speaking, reading, and writing. Learners and teachers can select the skills and strategies they need and plan their own route through the materials. The course can be used in conjunction with a regular language course or presented as separate learner training sessions.

E-Books for English Language Learning


Cisco Networkers 2009 Barcelona Sessions

Cisco Networkers 2009 Barcelona Sessions | 950 MB

Cisco Networkers 2009 takes place from Tuesday January 27 to Thursday January 29, 2009. In addition, on Monday January 26, we are offering Cisco Networkers delegates the option of attending Techtorials and 4-hour Labs at the same venue, at an extra cost.


ASA cisco video

ASA Security Context High Quality MP4 by Pranay
Configuring Event Action Rules.avi
Configuring IPsec Site-to-Site VPN.avi
Configuring the Meta Event Generator.avi
Configuring Transparent Firewall on the ASA and PIX Security Appliances (QLM) - iPOD
Hardening Cisco IOS Devices.avi

Cisco ASA 5500 Series

Cisco ASA 5500 Series Adaptive Security Appliance AND Cisco Adaptive Security Device Manager (ASDM) PRODUCT CD

Windows Platforms
If your CD does not auto-launch, do the following:
1) View the CD files.
2) Click on cdhome.html to start the CD.

If clicking on cdhome.html does not launch your web browser, then do the following:
1) Open your web browser.
2) Go to File > Open.
3) Select the cdhome.html file.
4) Click OK.

UNIX Platforms
1) Mount the CD to your UNIX system.
2) View the CD files.
3) Copy the file needed to your system.

The software bin files are located under /software.
The technical documentation is located under /docs.
Instructions for installing your Cisco ASA 5500 Adaptive Security Appliance software are available as follows:

Cisco Unified Presence Server v7 March 2009

Cisco Unified Presence Server v7 0 March 2009 Updated
The Cisco Unified Presence Server is a critical component for delivering the full value of a Cisco Unified Communications environment. It collects information about a user’s availability status, such as whether or not you are using a communications device such as a phone at a particular time. It also collects information regarding a user’s communications capabilities, such as whether web collaboration or video conferencing is enabled.
Cisco Unified Presence Server enables you to deploy Session Initiation Protocol (SIP) technology to support the voice services in your enterprise environment.
Cisco Unified Presence is a standards-based platform that collects information from multiple sources about user availability and communications capabilities to provide rich presence status and facilitate presence-enabled communications with Cisco Unified Communications and other critical business applications.


CCNA Security Official Exam Certification Guide

CCNA Security Official Exam Certification Guide (Exam 640-553) with CD

CCNA Security Official Exam Certification Guide is a best of breed Cisco® exam study guide that focuses specifically on the objectives for the CCNA® Security IINS exam. Senior security instructors Michael Watkins and Kevin Wallace share preparation hints and test-taking tips, helping you identify areas of weakness and improve both your conceptual knowledge and hands-on skills. Material is presented in a concise manner, focusing on increasing your understanding and retention of exam topics.
CCNA Security Official Exam Certification Guide presents you with an organized test preparation routine through the use of proven series elements and techniques. “Do I Know This Already?” quizzes open each chapter and allow you to decide how much time you need to spend on each section. Exam topic lists make referencing easy. Chapter-ending Exam Preparation Tasks sections help drill you on key concepts you must know thoroughly.
The companion CD-ROM contains a powerful testing engine that allows you to focus on individual topic areas or take complete, timed exams. The assessment engine also tracks your performance and provides feedback on a topic-by-topic basis, presenting question-by-question remediation to the text and laying out a complete study plan for review.
Well-regarded for its level of detail, assessment features, and challenging review questions and exercises, this official study guide helps you master the concepts and techniques that will enable you to succeed on the exam the first time.
CCNA Security Official Exam Certification Guide is part of a recommended learning path from Cisco that includes simulation and hands-on training from authorized Cisco Learning Partners and self-study products from Cisco Press. To find out more about instructor-led training, e-learning, and hands-on instruction offered by authorized Cisco Learning Partners worldwide, please visit
Michael Watkins, CCNA/CCNP®/CCVP®/CCSP®, is a full-time senior technical instructor with SkillSoft Corporation. With 13 years of network management, training, and consulting experience, Michael has worked with organizations such as Kraft Foods, Johnson and Johnson, Raytheon, and the United States Air Force to help them implement and learn the latest network technologies.
Kevin Wallace, CCIE® No. 7945, is a certified Cisco instructor working full time for SkillSoft, where he teaches courses in the Cisco CCSP, CCVP, and CCNP tracks. With 19 years of Cisco networking experience, Kevin has been a network design specialist for the Walt Disney World Resort and a network manager for Eastern Kentucky University. Kevin also is a CCVP, CCSP, CCNP, and CCDP with multiple Cisco security and IP communications specializations.
The official study guide helps you master all the topics on the IINS exam, including
Network security threats
Security policies
Network perimeter defense
AAA configuration
Router security
Switch security
Endpoint security
SAN security
VoIP security
IOS firewalls
Cisco IOS® IPS
Digital signatures
PKI and asymmetric encryption
IPsec VPNs
This volume is part of the Exam Certification Guide Series from Cisco Press®. Books in this series provide officially developed exam preparation materials that offer assessment, review, and practice to help Cisco Career Certification candidates identify weaknesses, concentrate their study efforts, and enhance their confidence as exam day nears.
Category: Cisco Press—Cisco Certification
Covers: IINS exam 640-553

TELL ME MORE PERFORMANCE English (10 levels of learning)

TELL ME MORE® PERFORMANCE is the most complete and extensive English software available anywhere. Become fluent in English through 10 distinct levels, and utilizing exclusive online services:
A 24/7 online adviser to answer your questions
Comprehensive Tests to evaluate your level and progress
Weekly lessons based on a relevant news topic
New Role Play activity
TELL ME MORE® PERFORMANCE provides language learning that is simple-to-use and increasingly effective, making learning a language fun and engaging. It’s so effective, in fact, that more than 95% of learners have progressed at least one level!*
*IDC Study – after 50 hours of learning
2,000 hours of English learning and 10 different levels
TELL ME MORE® PERFORMANCE is the most comprehensive method on the market, allowing you to choose from 10 distinct levels of content, from Complete Beginner to Expert.

10,000 exercises
Covers all the skills to learn English: speaking and listening, reading and writing, grammar, vocabulary, and culture. Learn in an interactive way with dialogues, speech recognition and other cutting edge software.

The most powerful speech recognition technology on the market
TELL ME MORE® PERFORMANCE includes the latest speech recognition technology, giving you the most effective way of assessing your pronunciation. You will improve your English conversational skills with graphs and 3D animations, while interactive dialogues with the computer make your English learning experience fun.

10 hours of video
Full immersion in the language and culture through cultural videos – or play the part of a character in the Role Play activity.

A 24/7 online adviser
Need help learning how to use the software? Have questions about how the software works and want an answer right away? Our advisers are ready to help you 24 hours a day, 7 days a week, and will answer your questions for free by chatting with you online.

Real News Broadcasts
Experience a new TELL ME MORE® lesson every week online, in partnership with EuroNews®. In 30 minutes you will learn about a current news topic with video, vocabulary and grammar exercises incorporated directly into the broadcast.

Test your progress
At any time during the course, you can take a test to evaluate your progress.

Learn on the go with TELL ME MORE®

Continue your English learning wherever you go:
On your PocketPC (MPEG videos, audio files, cultural texts, etc.)
On your MP3 player (Including iPods and other MP3 devices)
On audio CDs
On printable vocabulary lists and grammatical explanations


Learning English Step


Step 1

Step 2

Step 3


how to use

Cisco ASA, PIX, and FWSM Firewall Handbook (2nd Edition)


Cisco ASA, PIX, and FWSM Firewall Handbook, Second Edition, is a
guide for the most commonly implemented features of the popular
Cisco? firewall security solutions. Fully updated to cover the
latest firewall releases, this book helps you to quickly and easily
configure, integrate, and manage the entire suite of Cisco firewall
products, including ASA, PIX?, and the Catalyst? Firewall Services
Module (FWSM).


Cisco Networking Simplified (2nd Edition)


Author: Neil Anderson, Paul L. Della Maggiora and Jim Doherty
Paperback: 432 pages
Publisher: Cisco Press; 2 edition (January 19, 2008)
Language: English
ISBN-10: 1587201992
ISBN-13: 978-1587201998
Format: pdf
Now 100 percent updated for the latest technologies, this is today’s easiest, most visual guide to Cisco® networking. Even if you’ve never set up or managed a network, Cisco Networking Simplified, Second Edition, helps you quickly master the concepts you need to understand. Its full-color diagrams and clear explanations give you the big picture: how each important networking technology works, what it can do for you, and how they all fit together. The authors illuminate networking from the smallest LANs to the largest enterprise infrastructures, offering practical introductions to key issues ranging from security to availability, mobility to virtualization.
What you always wanted to know about networking but were afraid to ask!
How networks and the Internet work
How to build coherent, cost-effective network infrastructures
How to design networks for maximum reliability and availability
What you need to know about data center and application networking
How to secure networks against today’s threats and attacks
How to take advantage of the latest mobility technologies
How virtualizing networks can help businesses leverage their network investments even further
How to combine messaging, calendaring, telephony, audio, video, and web conferencing into a unified communications architecture.

Wednesday, April 8, 2009

Switching to VoIP [ILLUSTRATED]

ISBN 10 :0596008686
Author(s) :Theodore Wallingford
Pages :477
Description:More and more businesses today have their receive phone service through Internet instead of local phone company lines. Many businesses are also using their internal local and wide-area network infrastructure to replace legacy enterprise telephone networks. This migration to a single network carrying voice and data is called convergence, and it's revolutionizing the world of telecommunications by slashing costs and empowering users. The technology of families driving this convergence is called VoIP, or Voice over IP.
VoIP has advanced Internet-based telephony to a viable solution, piquing the interest of companies small and large. The primary reason for migrating to VoIP is cost, as it equalizes the costs of long distance calls, local calls, and e-mails to fractions of a penny per use. But the real enterprise turn-on is how VoIP empowers businesses to mold and customize telecom and datacom solutions using a single, cohesive networking platform. These business drivers are so compelling that legacy telephony is going the way of the dinosaur, yielding to Voice over IP as the dominant enterprise communications paradigm.
Developed from real-world experience by a senior developer, O'Reilly's Switching to VoIP provides solutions for the most common VoIP migration challenges. So if you're a network professional who is migrating from a traditional telephony system to a modern, feature-rich network, this book is a must-have. You'll discover the strengths and weaknesses of circuit-switched and packet-switched networks, how VoIP systems impact network infrastructure, as well as solutions for common challenges involved with IP voice migrations. Among the challenges discussed and projects presented:

building a softPBX
configuring IP phones
ensuring quality of service
topological considerations
coordinating a complete system ?switchover?
migrating applications like voicemail and directory services
retro-interfacing to traditional telephony
supporting mobile users
security and survivability
dealing with the challenges of NAT
To help you grasp the core principles at work, Switching to VoIP uses a combination of strategy and hands-on "how-to" that introduce VoIP routers and media gateways, various makes of IP telephone equipment, legacy analog phones, IPTables and Linux firewalls, and the Asterisk open source PBX software by Digium. You'll learn how to build an IP-based or legacy-compatible phone system and voicemail system complete with e-mail integration while becoming familiar with VoIP protocols and devices. Switching to VoIP remains vendor-neutral and advocates standards, not brands.


Oracle - April 2009

Oracle - April 2009
English | pdf | 13.7 MB