Silicon Laboratories, Inc. · NASDAQ:SLAB
Silicon Laboratories — Technical Presentation
37 slides from Silicon Laboratories's technical presentation
Slide 1: Wi-Fi Technology presentation
Wi-Fi® Technology presentation name
Slide 2: Topics
Topics Background Benefits 802.11 Architecture Wi-Fi Future Wi-Fi® Alliance Certification More Information
Slide 3: The IEEE 802.11 specification is an international standard
The IEEE 802.11 specification is an international standad describing the characteristics of a wireless Local Area Network The term Wi-Fi suggests Wireless Fidelity, resembling the long- established audio-equipment classification term high fidelity
Slide 4: Background
GIT sis= Background
Slide 5: Background
Background 1990 : 802.11 development started by IEEE The aim was to develop a standards for medium access control (MAC) and physical layer (PHY) 1997 : First version of 802.11 standard was ratified First version delivered 1Mb/s and 2Mb/s data rates 1999 : 802.11a and 802.11b amendments were released
Slide 6: Background
Background 2009 : 801.11n amendment were ratified PHY relies heavily on multiple-input multiple-output (MIMO) technology Can use both 2.4Ghz and 5Ghz at the same time Throughput increased even up to 600Mbps 2009 : Bluetooth 3.0 + HS 802.11 selected as the Bluetooth high speed channel 2009 : Wi-Fi di
Slide 7: Benefits
GIT sis= Benefits
Slide 8: Benefits of Wi-Fi
Benefits of Wi-Fi Mobility Compatibility with IP networks High speed data Unlicenced frequencies Security Easy and fast installation Scalability Installed infrastucture Low cost
Slide 9: Eco-System Growth
Eco-System Growth The number of Wi-Fi products is growing steadily. By iSuppli Market Research
Slide 10: 802.11 Architecture
GIT sis= 802.11 Architecture
Slide 11: 802.11 Architecture
802.11 Architecture Application HTTP, FTP, SMTP etc. DHCP, RTP, TFTP etc. Host TCP UDP IP 802.2 Logical Link Control (LLC) 802.11 Media Access Control (MAC) Radio Physical layer (PHY) (802.11b DSSS, 802.11g OFDM, 802.11n MIMO etc.)
Slide 12: Physical layer
Physical layer 2.4 GHz and/or 5GHz transciever Industrial Scientific Medical (ISM) band License free Spread spectrum technology FHSS, DSSS abnd OFDM modulations FHSS (Frequency Hopping Spread Spectrum) Bandwidth divided into 75 1MHz channels Data throughput limited to 2Mbps because of hopping overhe
Slide 13: Physical layer
Physical layer 10 11 12 13 14 1 2 3 4 5 6 7 8 9 5Mhz 22MHz 2412MHz 2472MHz 2484MHz Europe : channels 1-13 USA : channels 1-11 Japan : channels 1-14
Slide 14: Physical layer
Physical layer Standard Frequency Bandwidth Symbol rate (Mb/s) MIMO streams Modulation 802.11 2.4GHz 20 1, 2 1 DSSS, FHSS 802.11a 5Ghz 20 6, 9, 12, 18, 24, 36, 48, 54 1 OFDM 802.11b 2.4GHz 20 5.5,11 1 DSSS 802.11g 2.4GHz 20 6, 9, 12, 18, 24, 36, 48, 54 1 OFDM, DSSS 20 7.2, 14.4, 21.7, 28.9, 43.3, 57
Slide 15: 802.11 Media Access Control (MAC)
802.11 Media Access Control (MAC) Manages and maintains communications between 802.11 stations and clients Coordinates access to shared radio channels Uses CSMA/CA algorithm to access the media (Carrier Sense Multiple Access / Collision Avoidance) Similar to Bluetooth Link Layer
Slide 16: 802.11 Media Access Control (MAC)
802.11 Media Access Control (MAC) Function Explanation Scanning Scanning of access points. Both active (probe) and passive (beacon) scanning are provided by the standard. Authentication Authentication is the process of proving identity between the client and the access point. Association Once authen
Slide 17: Logical Link Control (LLC)
Logical Link Control (LLC) The LLC provides end-to-end link control over 802.11-based wireless LAN LLC services: Unacknowledged connectionless service Higher layers must take care of error and flow control mechanisms Peer-to-peer, multicast and broadcast communication Connection-oriented service Err
Slide 18: Infrastructure
Infrastructure Basic Service Set (BBS) A set of stations controlled by a single “Coordination Function” Basic Service Set (BSS) Typically uses an Access Point (AP) Acces Point All mobile stations must be accessible by the (AP) access point of the infrastructure BSS In the infrastructure network, sta
Slide 19: Infrastructure
Basic Service Set (BSS) Infrastructure Extended Service Set (ESS) Mobile client Mobile client A set of one or more Basic Service Sets interconnected by a Distribution System (DS) Acces Point Traffic always flows via Access-Point (AP) Distribution System (DS): Distribution system (DS) A system to int
Slide 20: Infrastructure
Infrastructure AP – client services: Authentication : open, shared key or WPS De-authentication Privacy : WEP, WPA or WPA2 Distribution System services: Association : maps the client into the distribution system via access point Disassociation : release of association Distribution : used to deliver
Slide 21: Security
GIT sis= Security
Slide 22: Security
Security The 802.11 provides the following security features Association Client needs to associate with the Access Point Authentication Authentication is either open, shared key or WPS Access control Access Point can decide which clients are allowed to assiciate based on MAC address Trivial to spoof
Slide 23: Security
Security Encryption Wired Equivalent Privacy (WEP) (insecure) Wireless Protected Access (WPA) (insecure) Wireless Protected Access 2 (WPA2) (recommended) WAPI (for China) Data integrity Data can not be modified on-the-fly. Quaranteed by encryption. Data confidentiality No eavesdropping with decrypti
Slide 24: Security
Security Wired Equivalent Privacy (WEP) Wired Equivalent Privacy. This encryption standard was the original encryption standard for wireless. Security issues known since 2001, can be cracked in <1minute Wirelsss Protected Access (WPA) A software/firmware improvement over WEP. WPA is a trimmed-down v
Slide 25: Security
Security Wireless Protected Access 2 (WPA2) WPA2 is a Wi-Fi Alliance branded version of the final 802.11i standard. The primary enhancement over WPA is the inclusion of the AES- CCMP algorithm as a mandatory feature. The CCMP/AES algorithm is considered secure, given a good enough password WPA2 Pers
Slide 26: Wi-Fi Protected Setup
Wi-Fi Protected Setup The standard for easy and secure establishment of a wireless home network, created by the Wi-Fi Alliance. It is not a security scheme but just a way to configure one. The protocol is meant to allow home users who know little of wireless security. PIN entry (mandatory) Commonly
Slide 27: Upcoming technology
GIT sis= Upcoming technology
Slide 28: Wi-Fi Direct
Wi-Fi Direct Allows Wi-Fi devices to talk to each other without the need for wireless access points Wi-Fi Direct essentially embeds a software access point, or "soft AP", into any device that wishes to support Direct. Requires support for Wi-Fi Protected Setup with its push-button or PIN-based setup
Slide 29: Wi-Fi Multimedia - WMM
Wi-Fi Multimedia - WMM Quality of Service (QoS) targeting multimedia applications Implemented on MAC layer as amendment (IEEE 802.11e) For queues or categories: voice, video, best effort and background. No guaranteed throughput. WMM power save: Requires AP to buffer each queue Allows STA to request
Slide 30: IEEE 802.11ac
IEEE 802.11ac The next generation after IEEE 802.11n 433Mbit/s - 1Gbit/s datarates (not throughput) Working in the 5GHz band Currently being drafted Working group approval expected late 2013 Demonstrations done, products released 2012-2013 Througput through wider channels 80MHz and 160MHz More dense
Slide 31: Wi-Fi Alliance
GIT sis= Wi-Fi Alliance
Slide 32: Wi-Fi Alliance
Wi-Fi Alliance An open, non-profit organizaton responsible of : Wi-Fi standards development, marketing, Wi-Fi certification etc. Wi-Fi Alliance developed standards: WPA, WPA2, WMM, Wi-Fi Direct etc. Formed originally to resolve the interoperability issues between different manufacturers’ 802.11 devi
Slide 33: Certification
GIT sis= Certification
Slide 34: Certification
Certification Typical two step process: Wi-Fi certification (optional) Regulatory testing (FCC, CE, IC, Telec etc.) Consists of mandatory and optional certifications Mandatory IEEE 802.11 based radio standards WPA and WPA2 EAP Optional Wi-Fi Direct Wi-Fi Protected Setup WMM WMM Power save Wi-Fi Alli
Slide 35: More information
GIT sis= More information
Slide 36: More information
More information Bluegiga Technologies www.bluegiga.com IEEE 801.11 www.ieee802.org/11 www.en.wikipedia.org/wiki/IEEE_802.11 Wi-Fi Alliance www.wi-fi.org www.wi-fi.org/knowledge_center_overview.php
Slide 37: Thank you
Thank you www.bluegiga.com