CCNP Wireless CUWSS 642-732 Summary Notes 22 : Assessing RF Coverage

RF Audit The main objective is to verify RF Coverage. The goal is to validate or audit the current WLAN deployment in order to enhance its security and performance. Unlike pre installation site surveys, post installation surveys focus more on the entire site environment. Verify RF footprint of all installed APs. Use Ekahau Survey or AirMagnet Survey PRO. First … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 22 : Assessing RF Coverage

CCNP Wireless CUWSS 642-732 Summary Notes 21 : Infrastructure requirements Part 2

802.11n APs with 100% duty cycle: the 2,4 band when oversubscribed with clients communicating at 144 Mbps may consume up to 70 - 75 Mbps on wired side. the 5 GHz band when oversubscribed and using 40 MHz channels with clients communicating at 300 Mbps may consume up to 160 - 170 Mbps on wired side. Both … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 21 : Infrastructure requirements Part 2

CCNP Wireless CUWSS 642-732 Summary Notes 20 : Choosing Antennas

Antennas Antenna - “an intentional radiator of electromagnetic radiation. Electromagnetic field - a sine wave that has an electric component and a magnetic field component. Indoor antennas are always vertically polarized but this is not critical. Polarization plays a role in Outdoor links where a polarization mismatch can reduce the received signal by 20 dBm. Polarization … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 20 : Choosing Antennas

CCNP Wireless CUWSS 642-732 Summary Notes 19 : Infrastructure Requirements Part 1

AP Power  Options for powering the AP AP model-specific Power module (DC Power) Power Injector - combine 48-VDC power with the data signal, sending both to the access point or bridge. The AIR-PWRINJ3 power injector for Cisco Aironet 1130AG, 1140AG, and 1240AG Series Access Points works with the power supply provided with the access point. The Cisco Aironet Power … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 19 : Infrastructure Requirements Part 1

CCNP Wireless CUWSS 642-732 Summary Notes 18 : Hardware for the RF Network

Designing the RF network Define the APs and WLC requirements AP Density This depends on: Application requirements Data Networks (web browsing) 15 to 25 users per AP 802.11b users reduce a 802.11g AP throughput dramatically. The 802.11b client still has a maximum data rate of 11 Mb/s per second and a maximum throughput of 7.1 Mb/s. Data … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 18 : Hardware for the RF Network

CCNP Wireless CUWSS 642-732 Summary Notes 17 : Ekahau Site Survey

Ekahau Site Survey Tool  This tool is used to determine each AP coverage area. It records the signal level, retries, lost packets etc. Ekahau Site Survey comes in a standard version and a Pro version. Standard Pro adds the predictive survey which allows us to add obstacles to the map so as to predict how many APs will be … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 17 : Ekahau Site Survey

CCNP Wireless CUWSS 642-732 Summary Notes 16 : Layer 2 Active Site Survey using AirMagnet Survey Pro

AirMagnet Survey Layer 2 site survey can be performed with AirMagnet Survey PRO to determine the access point placement and coverage. AirMagnet Survey PRO has the capability of doing pre-site surveys (before the install) and post-site surveys (after the install), also known as an audit, to ensure adequate coverage. In the configuration menu: Select the SSID Set the Tx … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 16 : Layer 2 Active Site Survey using AirMagnet Survey Pro

CCNP Wireless CUWSS 642-732 Summary Notes 15 : Attenuation and Data Rates

RF Reflectors and Absorbers in the building Signal Attenuation Each 3-dB attenuation reduces the signal strength by half Moving objects may also affect the signal Break rooms and test labs may produce 2.4-GHz iinterference and create multipath distortion and RF shadows. Elevator shafts block and reflect RF signals. Supply rooms with inventory absorb RF signals. Interior offices … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 15 : Attenuation and Data Rates

CCNP Wireless CUWSS 642-732 Summary Notes 14 : Layer 1 Active Site Survey – Cisco Spectrum Expert

Cisco Spectrum Expert: Active Site Surveys (Layer 1 Sweep) Recommended tool of choice - Cisco Spectrum Expert With Cisco Spectrum Expert, you can detect, classify, locate, and mitigate sources of wireless interference to optimize network performance for mobility applications. Cisco Spectrum Expert is a combination of both hardware and software. Cisco Spectrum Expert is delivered as hardware in … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 14 : Layer 1 Active Site Survey – Cisco Spectrum Expert

CCNP Wireless CUWSS 642-732 Summary Notes 13 : Defining Site Survey Documentation

Define the Deliverables A site survey preassessment form to help determine the length and type of survey, what equipment will be needed, and what questions the engineer will need to ask during the walk through the facility. Pre-Assesment Form that summarizes customer requirements Customer contact information WLAN Objectives Building to be covered Physical Information and Building Size Number … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 13 : Defining Site Survey Documentation

CCNP Wireless CUWSS 642-732 Summary Notes 12 : Planning for Site Survey

Kickoff Meeting Arrange to meet up with the all the people that will be involved in the project from the sponsors to the IT to the security team. This is when you review and finalize the Statement of Work SoW Reconsile contradicting answers. Verify scope of the mission. Explain the expectations Let them know what … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 12 : Planning for Site Survey

CCNP Wireless CUWSS 642-732 Summary Notes 11 : Predictive Site Survey

Site survey could be done in 3 steps: Virtual site survey using a planning tool for a general overview ThisisusuallydoneusingtheWLC. First add the map of the area to be surveyed. Layer 1 sweep to discover existing RF Actual survey to establish the placing of the APs. Predictive Site Survey They do not take into account … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 11 : Predictive Site Survey

CCNP Wireless CUWSS 642-732 Summary Notes 10 : Designing a mesh network

Design Considerations (especially outdoors) Consider the data rate required at the edge of the cell Larger cells offer binary phase shift keying (BPSK) or quadrature phase shift keying (QPSK) data rates at the edge but require fewer hops to wired network. Smaller cells may offer quadrature amplitude modulation (QAM) (16QAM or even 64 QAM) at the edge hence … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 10 : Designing a mesh network

CCNP Wireless CUWSS 642-732 Summary Notes 9 : Mesh Networks

Indoor Mesh Networks This is an excellent way of providing coverage in hard to wire environments or where cables cannot be used or if cable length is too long (> 100 m). Indoor mesh access points: Cisco Aironet 1130 Series - controller based Cisco Aironet 1240 Series - controller based The APs deliver network access to … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 9 : Mesh Networks

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 7 : Survey Models

Data Only Coverage Does not require a large amount of overlap due to rate shifting; generally 5 to 10 percent, with 10 - 15  % overlap between the cells Separation of access points is typically 120 to 130 feet ( 37 to 40 m) 2.4 band 802.11b/g propagates through floors. The 5-GHz waveform of 802.11a has approximately … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 7 : Survey Models

CCNP Wireless CUWSS 642-732 Summary Notes 6 : Safety and Aesthetics Considerations

Safety Considerations Ladder and Aerial Lift Safety - horizontal distance from the top support to the footoftheladder is about one-fourth of the working lengthoftheladder. Do not  exceed the lift maximum load, taking into account the worker, the materials, and the tools. Self-supporting (foldout) and portable ladders that are not self-supporting (leaning) must be able to support at least … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 6 : Safety and Aesthetics Considerations

CCNP Wireless CUWSS 642-732 Summary Notes 5 : Regulatory Issues

Regulatory Domains: Several countries use the same regulatory rules, forming regulatory domains. They define such things as power of transmission, antenna gain and frequency used. A domain - US, Taiwan, Puerto Rico etc - Follow Federal Communication Commision rules E domain - Europe, Israel, Mexico, Singapore etc - follow Europe Telecommunication Standard Institute Rules Japan - follow Ministry … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 5 : Regulatory Issues

CCNP Wireless CUWSS 642-732 Summary Notes 4 : 802.11n hardware

When performing a survey for 802.11n, signal strength is not an accurate predictor of 802.11n performance. Multipath can actually enhance performance with 802.11n clients. 802.11n hardware Disadvantage of non-802.11 hardware is that they may have 2 antennas per band but they both are connected to the same radio circuit so when they receive a signal, the … Continue reading CCNP Wireless CUWSS 642-732 Summary Notes 4 : 802.11n hardware

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