CWNA Summary Notes: Legacy 802.11 Security | MAC Filters

MAC Filtering 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. Here is an example from my ASUS home router. Weakness: MAC addresses can easily be spoofed. Where used: Protect … Continue reading CWNA Summary Notes: Legacy 802.11 Security | MAC Filters

CWNA Summary Notes: Legacy 802.11 Security | Static WEP Encryption

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 … Continue reading CWNA Summary Notes: Legacy 802.11 Security | Static WEP Encryption

CWNA Summary Notes: Legacy 802.11 Security | Legacy Authentication

Legacy Authentication 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: Open System Authentication It provides authentication without performing any form of user verification Involved a 2 way exchange between … Continue reading CWNA Summary Notes: Legacy 802.11 Security | Legacy Authentication

CWNA Summary Notes: 802.11 Network Security Architecture

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 … Continue reading CWNA Summary Notes: 802.11 Network Security Architecture

CCNP Wireless CUWSS 642-732 Summary Notes 24 : Installation Report

Post Deployment 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 … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 24 : Installation Report

CCNP Wireless CUWSS 642-732 Summary Notes 8 : Bridging Models

Point to Point Wireless Links Cisco Aironet 1500 Series Access Point can use its backhaul radio to bridge two wired segments in point to point mode. Its a mesh network with only one MAP and no WLAN clients. If Ethernet bridging is enabled, then wireless client access can be provided but is not recommended if … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 8 : Bridging Models

CCNP Wireless CUWSS 642-732 Summary Notes 3 : RF Applications and Client Devices

RF Applications Data rate is just the link speed and not the throughput (download speed). 802.11b at an 11-Mbps data rate offers on average a 5.5-Mbps throughput. 11b usually degrades performance for other devices in the other bands. Avoid using this band, unless you have old devices. 802.11g at54Mbpsoffersonaveragea20-Mbps throughput butdegradesto6-Mbps throughput as soon as a 802.11b device … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 3 : RF Applications and Client Devices

CCNP Wireless CUWSS 642-732 Summary Notes 2 : Site Survey Preassessment

Site Survey Pre-assessment can be done using a questionnaire that should have most of this information to enable proper design planning for the WLAN. Customer contact information Total number of sites Is it a New vs existing deployment Band requirements Existing devices Data coverage type (VoWLAN, Data, Location services) Facility information - get maps for … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 2 : Site Survey Preassessment

CCNP Wireless CUWSS 642-732 Summary Notes 1 : Site Survey Requirements for Different Vertical Industries

A site survey is a task-by-task process in which the surveyor studies the facility to understand the RF behavior, discovers RF coverage areas, checks for RF interference, and determines the appropriate placement of wireless devices. Top considerations: Identify Customer Requirements  and his expectations. What type of environment? Consider the regulatory issues for that particular site Asses the … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 1 : Site Survey Requirements for Different Vertical Industries

CWNA Summary Notes: Coverage Analysis Methods

Manual Site Survey Passive manual survey - The radio card collects RF measurements but the client adapter is not associated to the access point during the survey, and all information is received from radio signals that exist at layer 1. Active manual survey - the radio card is associated to the access point and has layer 2 connectively, allowing … Continue reading CWNA Summary Notes: Coverage Analysis Methods

CWNA Summary Notes: Site Survey Tools

Indoor Site Surveys Tools Spectrum analyzer for RF spectrum analysis Blueprints or floor plans of the facility Received signal strength measurement tool 802.11 client card - prefer the vendor that will be deployed AP - preferably 2. Battery pack for AP and for the laptop Binoculars to view distant objects ( eg high ceiling and in … Continue reading CWNA Summary Notes: Site Survey Tools

CWNA Summary Notes: Spectrum and Coverage Analysis

Spectrum Analysis A noisy environment can cause the data in 802.11 transmissions to become corrupted -> the cyclic redundancy check (CRC) will fail -> the receiving 802.11 radio will not send an ACK frame to the transmitting 802.11 radio -> the unicast frame is not acknowledged and will have to be re-transmitted. Wi-Fi data networks can handle a retransmission rate … Continue reading CWNA Summary Notes: Spectrum and Coverage Analysis

CWNA Summary Notes: Capacity and Coverage Requirements

Capacity and Coverage Requirements Factors that should be considered when planning for Capacity: Data applications. For 802.11b/g network, 12 to 15 data users per AP ForVoWiFi SpectraLink recommends max of 12 calls per 11 Mbps cell (with 1 call needing 4.5 % of AP bandwidth), 7 calls per 2 Mbps (with 1 call needing 12% … Continue reading CWNA Summary Notes: Capacity and Coverage Requirements

CWNA Summary Notes: Procedures for Performing a Site Survey

Gather background data for the site survey Examine business requirements Why do they need a WLAN is mobility required What devices will be connecting What apps will be used What is the amount of bandwidth required by the user Conduct interviews with personnel One-on-one interviews Group interviews Facilitated sessions - a much larger group consisting of … Continue reading CWNA Summary Notes: Procedures for Performing a Site Survey

CWNA Summary Notes: Specialized Site Survey Tools

These tools include: dedicated site survey applications spectrum analyzers protocol analyzers documentation tools Voice over WiFi (VoWiFi) Tools and Surveys Dedicated Applications eg. Site Survey Analyzer These applications can send packets and then analyze both transmitting and receiving data. Settings included in  dedicated applications include: Destination MAC Address of the AP that will be tested Continuous Link Test … Continue reading CWNA Summary Notes: Specialized Site Survey Tools

CWNA Summary Notes: What is a Site Survey

A Site Survey is an in-depth examination and analysis of a WLAN site. Purpose of a Site Survey Achieve the best possible performance from the WLAN Certify that the installation will operate as promised Determine the best location for APs Develop networks optimized for a variety of applications Ensure that the coverage will fulfill the … Continue reading CWNA Summary Notes: What is a Site Survey