Wireless Networking Wireless Devices Module-7A
description
Transcript of Wireless Networking Wireless Devices Module-7A
Wireless Networking
Wireless Devices Module-7A
Jerry BernardiniCommunity College of Rhode Island
04/22/23 1Wireless Networking J. Bernardini
Presentation Reference Material
• CWNA Certified Wireless Network Administration Official Study Guide
(PWO-104), David Coleman, David Westcott, 2009, Chapter-10
04/22/23 Wireless Networking J. Bernardini 2
WLAN Client Devices
• PC Cards– ExpressCard– CardBus– PCMCIA– Some support external antennas
• USB devices– External cable– Variable position and antenna
• Compact Flash Devices• SD Devices• PCI Cards• Mini-PCI Cards
– Laptop applications
04/22/23 Wireless Networking J. Bernardini 3
Cisco Aironet 802.11b Client Adapters
• 2.4 GHz– 802.11b– 11 Mbps
• Include– PC Card – PCI Card– LMC Card– Mini PCI
Cisco Aironet 350 Series Mini PCI
• 2.4 GHz/802.11b embedded wireless for notebooks
• 100 mW transmit power• Must order through PC
manufactures (not orderable directly through Cisco)
Cisco Aironet 802.11a Client Adapter•5 GHz/802.11a– 54 Mbps
•Rate Shifting – 6, 9, 12, 18, 24, 36, 48, or 54
•Fixed data rates – User configurable option
•5 dBi Patch Antenna•CardBus interface•Transmit power settings:– 20 mW, 10 mW, and 5 mW
PCMCIA, (PC) Cards
Compact Flash
• Compact Flash, (CF) - CompactFlash Association, CFA
CF Wireless 802.11b (WiFi)
Wireless USB Adapters
PCI and ISA Adapters
Adapters
CF to PC
SD to USB
SD to PC
USB to Serial
Ethernet Adapters
Access Points• The Access Point (AP) is the device that provides access to
the WLAN• Each BSS has one AP and multiple Aps make an ESS• Two categories of APs are Fat and Thin Access Points• Thin AP’s are paired with a wireless LAN switch or controller
to offer additional functionality and centralization over Fat AP’s.
• Fat (Thick or Smart) AP’s are "fat" because they operate autonomously as members of a decentralized WLAN.
3Com Wireless LAN Switch WX1200 3Com AP3750 MAP
Autonomous or FAT Access Points
• Traditional wireless LANs use decentralized Fat access points
• Manual configuration required to set the power level, channel, security and other configurable parameters.
• Each access point is individually configured • Third party software solutions are often needed for
additional security and management capabilities• For large networks which quickly add to the total
cost of ownership.
04/22/23 Wireless Networking J. Bernardini 15
Autonomous AP Implementation
04/22/23 Wireless Networking J. Bernardini 16
Lightweight or Thin Access Points
• Centralized WLANs use a wireless controller to manage, process, and configure the RF environment
• Centralized WLANs use called thin or lightweight APs• Aps communicate directly with the central controller
with the wired network• All the functionality and intelligence is offloaded to
the controller• This provides a single point of administration for
various policies relating to security, intrusion detection, user roles, and software upgrades..
04/22/23 Wireless Networking J. Bernardini 17
Thin Access Points Implementation
04/22/23 Wireless Networking J. Bernardini 18
Access Points Market
04/22/23 Wireless Networking J. Bernardini 19
Cisco APsLinksys APs
Buffalo APs
Belkin APs
Access Point Features
• Support of various IEEE 802.11 standards– FHSS, DSSS, OFDM, 802.11a,b, g, n
• Support for various security standards– IEEE 802.11i, WEP, WPA, WPA2, PSK, RADIUS
• Support for QoS extensions– Wireless Multimedia (WMM), VoWLAN
• Fixed or Detachable Antenna– Omni-directional, Directional
• Filtering– MAC, Protocol
• Variable Power– Percent of Max or Actual Levels
04/22/23 Wireless Networking J. Bernardini 20
Power Over Ethernet (PoE) Support• Found on Enterprise and not on SOHO APs• Primary benefit is ability to install APs where no AC
power is present• IEEE 802.3af standard for PoE• PoE is supply by injectors or switches
04/22/23 Wireless Networking J. Bernardini 21
PoE Options and Power Source Equipment(PSE)
Active/PSE Switch
PD Access Point
DC Power
CAT-5e Ethernet
DC Power
CAT-5e Ethernet
PD Access PointSwitch
PSE Injector
AC Power
PSE Injector
AC PowerDC Power
CAT-5e Ethernet
SwitchAccess Point
Tap/Splitter
DCPower
1
2
3
Pins 4-5 +Power(48v)Pins 7-8 –Power
Wireless Bridges
• Provides a link between two WLAN segments• Not full described by IEEE 802.11• Vendor dependent• Two Modes – Root and Non-root
Point-to-Point
Point-to-Mulitpoint
Non-Root Root
Root
Non-Root
Non-Root
WLAN Bridge Modes and Components
• Root Mode – A bridge that acts as the hub to a group of bridges. – Only One Root-Bridge for PtP or PtMP links (important for tests)– For PtP link one Root-Bridge and one Non-Root Bridge
• Non-Root Mode – A member bridge of a group that is not the Root Bridge.
– Can also function as a standard AP– Can function as a repeater
Cisco Aironet 14003Com WLAN Bridge Proxim Quick Bridge 11
Bridge Application: School District
LincolnElementaryYagi
BodeElementaryYagi
RichardsonElementaryYagi
PriceElementaryYagi
Dewitt ElementaryYagi
BolichMiddle SchoolYagi
RobertsMiddle SchoolDish
Weaver-Special EducationDish
High School 2 BridgesOne 12 dBi omniOne Dish Administration
2 BridgesOne 12 dBi omniOne Yagi
U N I V E R S I T YU N I V E R S I T Y
Channel #11
Channel #6
Channel #1
Residential WLAN Gateways
• Same as SOHO wireless routers• Support of various IEEE 802.11 standards
– FHSS, DSSS, OFDM, 802.11a,b, g, n
• Support for various security standards– IEEE 802.11i, WEP, WPA, WPA2, PSK, RADIUS
• Built in firewall features• Packet and MAC Filtering• Switched Ethernet ports• DHCP• NAT and PAT
04/22/23 Wireless Networking J. Bernardini 26
Enterprise WLAN
04/22/23 Wireless Networking J. Bernardini 27
Enterprise Wireless Gateways• Enterprise Wireless Gateway – is a powerful device that
interfaces between the enterprise network and the corporate firewall. – HTML WML– Authentication, Filtering, and Security– Traffic Management, QoS– Mobile Addressing
Vernier IS 6500p
BlueSecure ControllerBSC 2100
Enterprise Wireless Gateways
EnterpriseGateway
Internet
Router
AccessPoints
Switch
WirelessClients
EnterpriseServer
Wireless Mesh Access Points
• Mesh APs associate with multiple APs• Association between APs is limited by vendor (3-5)• Currently vendor dependent• Clients can reach destinations thru multiple APs• APs route packets to ovoid failures and optimal paths• Mesh Networks are more resilient• Not every AP has to be connected to a wired network• Self-Healing, Self-Configuring using Layer-2 Protocol• New standard IEEE 802.11s will allow interoperability
between vendors
04/22/23 Wireless Networking J. Bernardini 30
Wireless Mesh Network Implementation
04/22/23 Wireless Networking J. Bernardini 31
Voice Over IP WLAN (VoWLAN)
• Telephone communication using a WLAN requires latency and QoS considerations
• Special equipment is required– VoWLAN phone (phones that will connect to WLAN)– WLAN infrastructure with QoS (low latency and Protocol management)– Call management (PBX for IP phones)– Voice gateway for outside calls
• IP phones associate with APs rather than cellular towers
04/22/23 Wireless Networking J. Bernardini 32
LinksysSiemens