Latest Event Updates
It is day one of the month, hence the best time to plan my study hours. Here is the study plan for July. You can watch my progress as the days go by.
The Red days indicates days when I did not study at all. Let’s face it, we are all human and we have a tendency of being lazy 🙂. Yellow is for days when I did actually study but did not meet the planned number of hours. Finally,Green symbolizes the days when I actually studied the planned number of hours. Dark green (which is no where right now), will indicate the days when I did more than was expected of me.
We are half way through the year but It feels like the year has just begun. The plans remain unaccomplished, the dreams get bigger by the day but reality is a sad little story :). When I think that am a tad wiser, I get slapped back and realize that am actually stupidier than I thought I was initially. But then again, there is still hope. We are only half way through the year. Giving up is definitely not an option. Head held high. Eyes on the price. It’s time for my mid-year revolution.
If you are studying for CCNP Wireless or CWNP Certification, an essential part of the study process is actually getting to lab it all out so as to understand the concepts. I noticed that my Wireshark output lacked the 802.11 management or control packets while trying to capture Open System Authentication process. This blog will explain how to set up Wireshark for WLAN Capturing so that you do not miss the vital packet exchanges.
Read the rest of this entry »
This study plan was inspired by Rasika. Check out his blog. Very informative.
The Red days indicates days when I did not study at all. Let’s face it, we are all human and we have a tendency of being lazy :). Yellow is for days when I did actually study but did not meet the planned number of hours. Finally, Green symbolizes the days when I actually studied the planned number of hours. Dark green (which is no where right now), will indicate the days when I did more than was expected of me. Will that day ever come :(?? Sigh Read the rest of this entry »
When I think of the CWNP Program, I think of actual Wireless knowledge that Vendor oriented programs have failed to deliver. I have always used CWNP books to complement information that was missing during my past CCNP Wireless exams (2 more to go). It was therefore only logical that I would turn to their CWSP book to help me prepare for the next exam – 642-737 IAUWS.
Luckily, the new CWSP-205 study guide had just been published so I figured I would order it. Got the book yesterday and I have to say, am a tad disappointed. I have not read the book. I simply skimmed through it to see what is included and to be honest, I cannot help but compare it with the previous CWSP book published by Sybex. Read the rest of this entry »
MAC Filtering referes to the use of MAC addresses to client devices that can authenticate to a WLAN. MAC Filtering is not defined by 802.11 Standard and any implementation of it is Vendor specific. Read the rest of this entry »
Static WEP Encryption
This is a layer 2 encryption method using RC4 streaming cipher.
Main goals of WEP Encryption were:
- Confidentiality (Data privacy through encryption)
- Access Control ( Authorization if static WEP keys match)
- Data Integrity ( Data Integrity Check-sum is computed before encryption to ensure that the data has not been tampered with)
Can be entered as a hex (0 – 9) or ASCII (A – F) characters.
Static WEP Encryption was on 2 forms: Read the rest of this entry »
Legacy authentication methods were more of an authentication of capability (verification between two devices that they were valid 802.11 devices) and not so much an authentication of user identity.
They are of two types: Read the rest of this entry »
Components of a Secure Network
Required components when securing a network are:
Data Privacy and Integrity
Access to Wireless medium is unrestricted hence the use of cipher encryption technologies is needed for proper data privacy.
A cipher is an algorithm that is used to perform encryption:
- RC4 algorithm ( Ron’s Code / Rivest Cipher)
- It encrypts data in a continuous stream (streaming cipher)
- Used in technologies used to protect Internet traffic eg SSL (Secure Socket Layer)
- Incorporated into 2 legacy encryption methods: WEP and TKIP
- Advanced Encryption Standard Algorithm (AES) / Rijndael Algorithm
- Encrypts data in fixed blocks
- Much stronger than RC4
- Uses Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP) encryption method
- Encryption key strength options are 128, 192 or 256 bits.
To connect, the client must go through the following:
Scanning for networks
Includes passive or active scanning mode (or both). Many vendors use both.
- Client tunes to each channel, listens for a period of time, and monitors 802.11 beacon frames (AP transmits beacons by default every 100 milliseconds on a specific RF)
- Client records the RSS of the frame and continues scanning other channels.
- After scanning all RFs, the client decides which AP to join (usually highest RSS or more information eg SNR)
Most may have noticed a huge gap from January and that the Mobility summary notes are incomplete yet I have jumped straight to listing some CCIE Wireless v3 notes. This does not mean that I have stopped my incomplete CCNP Wireless Journey. In January, I noticed that I was rather behind schedule and decided that jotting my notes on pen and paper would fasten my speed a little. Yes, am that archaic! So basically, I have my notes and all I need to do is transfer them here. You know what they say, it takes 3 or more times to clearly understand the concepts – read, write, blog :). Read the rest of this entry »
Angulation (Angle-Based) Techniques
Localization is based on the angle of the received signal.
Angle of Arrival (AoA) / Direction of Arrival (DoA)
AoA determines the angle of Incidence at which signals arrive at the receiving sensor. This angle is used to estimate the location of the device using the intersection of the two lines of bearing (LoB) formed by a radical line to each receiving sensor. For 2D planes, 2 receivers are needed. When at least 3 receivers are used, this is known as triangulation. Read the rest of this entry »
Received Signal Strength (RSS)
Localization is based on the received signal strength. The RSS is measured either by the mobile device or by the receiving sensor.
The following information is needed to calculate the distance between the sensor and the device:
- Transmitter output power
- Cable losses
- Antenna gain
- Path loss model(PL)
CCNP Wireless 642-747 IUWMS Summary Notes 3 : Location Tracking Techniques – Lateration (ToA and TDoA)
Distance-Based (Lateration) Techniques
The tracking position is determined based on distance. The distance can be measured in three different ways:
- Using Time of Arrival (ToA)
- Using Time Difference of Arrival (TDoA)
- Using Received Signal Strength
In ToA and TDoA, localization is based on propagation time, whereas for RSS systems, propagation is based on signal strength.
Tracking systems are classified by the measurement technique that they use. Real Time Location Systems (RTLS) are grouped into the following:
- Cell of Origin ( Nearest Cell)
- Lateration ( depending on Distance)
- Angulation (depending on the angle)
- Location patterning ( pattern recognition)
Advantages of Location-based services.
Location-based services helps us to:
- Effectively locate assets and personnel.
- Improve productivity by locating effectively.
- Reduce unauthorized removal of assets and, thus, helps reduce losses.
- Improve customer satisfaction
- Improve WLAN planning and tuning
- Coordinate device location with Security policy enforcement
- Determine rogue device location
- Monitor health and status of key assets.
- Wi-Fi Location-Based Services 4.1 Design Guide by Cisco Press.
Happy New Year and thank you for sticking with me thus far !
In this post, I will share my CUWSS experience.
I finished studying for my CUWSS Exam in the beginning of December and booked my again for around December the 15th. My first attempt to give the exam was unsuccessful :(. To be honest, I was rather lazy during my preparation and was not as dedicated as was supposed to be. I did not go the extra mile to look for information and that might have contributed to my failure. I thought that going through the Study guide for the previous version of the exam (since I could not access the newer one), the Quick Reference Guide from v2.0, the IP Expert Videos for v1.0 and my extensive WiFi experience was enough to ace that exam, but No! I Failed. Read the rest of this entry »
A detailed hardware requirement list should have:
Wireless equipment needed
Supporting infrastructure upgrades
- RF Validation for the installed wireless network
- Co channel interference and appropriate channel separation
- Power levels are consistent with site survey
- If designing for AP failover or designing to RRM
- RF Coverage (band by band)
- Roaming audit
- Airmagnet can be used in active and also using IPERF
- Wireless Infrastructure
- If designing especially globally, verify channel allocation is consistent
- For 5 GHz band, make sure that the clients support all those UNI bands.Verify that RRM is consistent with what was achieved during survey
- Application testing
- Validate all layers 1 through 7
Installation Report / Deliverables
This report describes the deployment methodology and the tests that were performed to validate the installation.
The report should include the following:
- Spectrum analysis
- RF coverage analysis
- Hardware placement and configuration
- Application analysis – Includes results from application throughput testing
WCS can be used to assess Wireless coverage readiness for both Location Services and VoWLAN. This however does not replace an onsite post-deployment site survey. The tools used are:
- Inspect VoWLAN Readiness
- Inspect location Readiness
Both tools are launched from the map that you are viewing on WCS. Read the rest of this entry »