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Sideseadmed (IRT0040) 2.5 AP

Sideseadmed (IRT0040) 2.5 AP. Avo LOENG 2. Operator A. Joint frequency range. Joint radio access system. Operator B. Operator N. Raadiressursi jaotus. Infrastructure based networks.

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Sideseadmed (IRT0040) 2.5 AP

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  1. Sideseadmed (IRT0040)2.5 AP AvoLOENG 2

  2. Operator A Joint frequency range Joint radio access system Operator B Operator N Raadiressursi jaotus

  3. Infrastructure based networks Uses fixed base stations (infrastructure) which are responsible for coordinating communication between the mobile hosts (nodes)

  4. Hidden Nodes - a QoS Issue • If you can’t see a frame you can’t avoid colliding • RF characteristics make it hard to see all frames • Hidden nodes usurp priority and break service commitments • Only the AP can see and be seen by all nodesHidden

  5. The Light Weight Access Point Protocol is used between APsand a WLAN Controller • LWAPP carries control and data traffic between the two • It facilitates centralized management and automated configuration • Open, standards-based protocol • –Submitted to IETF CAPWAP WG

  6. Lightweight AP WLAN Concept

  7. Autonomous Deployments • Each AP had its own view of the network – like standalone cell towers • No hierarchical view of the RF – or the network

  8. Centralization – not a new idea • Original cellular networks were nodal. • Lots of call drops • Lots of administration • Roaming wasn’t very good • Not capable of providing advanced services

  9. Enter the Base Station Controller • Complete view of the network • Improved roaming • One point of administration • Enabled provisioning of advanced services Management/Control Base stations are used to handle call setup, handovers, and other functions across an entire cellular network.

  10. DHCP DNS RADIUS ACS HPOV Enter The Wireless Controller Control and Management LWAPP

  11. System Layers

  12. Basic LWAPP Architecture AC LWAPP (C=0) 802.11 AssocReq LWAPP (C=0) 802.11 AssocResp LWAPP (C=0) 802.11 Data Frame WTP 802.11 AssocReq 802.11 AssocResp 802.11 Data Frame STA

  13. Unified Advanced Services • Unified cellular and Wi-Fi VoIP. Advanced threat detection, identity networking, location-based security, asset tracking and guest access. • Same level of security, scalability, reliability, ease of deployment, and management for wireless LANs as wired LANs. • Integration into all major switching and routing platforms. Secure innovative WLAN controllers. Mobility Platform • Ubiquitous network access in all environments. Enhanced productivity. Proven platform with large install base and 61% market share. Plug and play. World-Class Network Management Network Unification Client Devices • 90% of Wi-Fi silicon is Certified. “Out-of-the-Box” wireless security. Unified Wireless Network

  14. Centralized Wireless LAN Architecture • Controller • 802.11 MAC Mgmt – (re)association requests & action frames • 802.11 data – encapsulate and sent to AP • 802.11e Resource Reservation – control protocol carried to AP in 802.11 mgmt frames – signaling done in the controller. • 802.11i Authentication & Key exchange WLAN Controller LWAPP • AP • 802.11 – beacons, probe response, auth (if open) • 802.11 control – packet ack & retransmission (latency) • 802.11e – frame queuing & packet prioritization (real-time access) • 802.11i – Layer 2 encryption Lightweight Access Points

  15. LWAPP • LWAPP - Light Weight Access Point Protocol is used between APs and WLAN Controller • LWAPP carries control and data traffic between the two • Control plane is AES-CCM encrypted • Data plane is not encrypted • It facilitates centralized management and automated configuration • Open, standards-based protocol (Submitted to IETF CAPWAP WG) Business Application Data Plane LWAPP Access Point Controller WiFi Client Control Plane

  16. Protocol for Centralization • LWAPP = LightWeight Access Point Protocol • Standardized Interface between an access point and a centralized controller • Defines: • Association of APsAuthentication of APsControl of APs • Works across L2 / L3 boundaries • Design goals: • Zero-config deployment • Secure deployment • Centralization • Controllers • Security Policies • Wireless IDS • QoS Policies • RF Management • Mobility Management • IPSec Encryption • Access Points • Remote RF interface • Timing critical functions • L2 Encryption

  17. LWAPP ModesLayer 2 • Layer 2 LWAPP is in an Ethernet frame (Ethertype 0xBBBB) • Cisco WLAN Controller and AP must be connected to the same VLAN/subnet Cisco WLAN Controller LWAPP-L2 LWAPP-L2 : Data Message Lightweight Access Points MAC Header LWAPP Header (C=0) Data … LWAPP-L2 : Control Message MAC Header LWAPP Header (C=1) Control Msg Control Elts …

  18. LWAPP ModesLayer 3 • Layer 3 LWAPP is in a UDP / IP frame • Data traffic uses source port 1024 and destination 12222 • Control traffic uses source port 1024 and destination port 12223 • Cisco Controller and AP can be connected to the same VLAN/subnet or connected to a different VLAN/subnet • Requires IP addressing of Cisco Lightweight AP Cisco WLAN Controller LWAPP-L3 LWAPP-L3 LWAPP-L3 LWAPP-L3 : Data Message Lightweight Access Points MAC Header IP UDP=12222 LWAPP Header (C=0) Data … LWAPP-L3 : Control Message MAC Header IP UDP=12223 LWAPP Header (C=1) Control Msg Control Elts …

  19. The need for Client Mobility Controller 1 Controller 2 • Wireless LAN is not only about wire-less • Need for mobility, and not only “hotspot” connectivity • Mobility is when a client move from one Access Point to an other • Access points can be on a single Controller or on different Controller • Client need to keep IP connectivity (same IP address) • Client Mobility is mandatory for some applications (Voice, Video, Business Applications, …) Subnet A Subnet B AP D AP A AP B AP C

  20. Client Mobility • Different Client Mobility levels • L2 Mobility • L3 Mobility : Conceptually similar to Proxy Mobile IP • Foreign and Anchor Controllers • Asymmetric traffic flow • What about Security ? • PKC – Proactive Key CachingWPA2 / 802.11i Fast Roaming

  21. Mobility Groups • Mobility Group is a “Cluster of Controllers” that share information between them (e.g. client context and state, controller “load”, etc.) • Up to 24 Controllers per Mobility Group • Mobility Group facilitates seamless roaming at both L2 & L3 • Configuring a Mobility Group: • IP connectivity between all devices • Same Mobility Group Name (IS case sensitive) • Same Virtual Interface IP address • Each device is configured with the MAC and IP of every other device in the group

  22. Client Database move MAC, WLAN, AP, QoS, IP, Sec,… Mobility Announcement Layer 2 Mobility Controller 1 Controller 2 • All controllers in same Mobility Group • Client connects to AP A on Controller 1 • Client database entry created • Client roams to AP B on Controller 1 • Proactive Key Caching (PKC) provides fast roam times for WPA2/802.11i clients. No need to re-authenticate to Radius server. • Client roams from AP B (Controller 1) to AP C (Controller 2) • Controller 2 makes a Mobility Announcement to peers in Mobility Group looking for Controller with client MAC • Controller 1 responds, handshakes, ACKs • Client database entry moved to Controller 2 • PMK data included (master key data from Radius server) • Proactive Key Caching provides fast roam times for WPA2/802.11i clients . No need to re-authenticate to Radius server. AP D AP A AP B AP C • Roam is transparent to client • Same DHCP address maintained • Proactive Key Caching with WPA2/802.11i(Funk or MS client)

  23. Client Database Client Database MAC, WLAN, IP, Sec, ANCHOR… MAC, WLAN, IP, Sec, FOREIGN… copy Mobility Announcement Layer 3 Mobility Ethernet in IP Tunnel Controller 1 Controller 2 • All controllers in same Mobility Group • Ethernet in IP Tunnels automatically created between controllers • Client connects to AP B on Controller 1 • Client database entry created as ANCHOR • Client roams to AP C on Controller 2 • Controller 2 makes a Mobility Announcement to peers in Mobility Group looking for Controller with client MAC • Controller 1 responds, handshakes, ACKs • Client database entry copied to Controller 2 • Marked as FOREIGN • PMK data included (master key data from Radius server) • Proactive Key Caching provides fast roam times for WPA2/802.11i clients. No need to re-authenticate to Radius server. • Client roams to AP on 3rd Controller • Same as above except FOREIGN client DB entry moved from previous Foreign Controller Subnet A Subnet B AP D AP A AP B AP C • Roam is transparent to client • Traffic from client to network exits at Foreign Controller • Traffic to client tunneled from Anchor to Foreign Controller • Same DHCP address maintained • Proactive Key Caching with WPA/802.11i (Funk or MS client)

  24. Corp SSID Corp SSID Specific Mobility : Guest Access • The traditional approach to segmenting guest traffic requires ‘pulling’ the guest VLAN through the corporate network • Many companies can’t or won’t do this Internet Corp User Isolated Guest Corp Intranet Internet 802.1Q WLAN Controller (Policy) LWAPP AP LWAPP AP Guest SSID Guest SSID

  25. Corp SSID Corp SSID Tunnel Guest Traffic • By tunneling all guest traffic to a DMZ controller, traffic originates and terminates in the DMZ • Guest clients logically reside in the DMZ network • No changes required to existing infrastructure except adding FW rules • Add additional DMZ controllers for scalability • Each DMZ controller can handle up to 40 tunnels Internet Guest WLAN Controller EoIP IP Proto 97 “Guest Tunnel” Corp Intranet WLAN Controller WLAN Controller LWAPP AP LWAPP AP Guest SSID Guest SSID

  26. Ad-hoc networks • Consists of mobile nodes which communicate with each other through wireless medium without any fixed infrastructure

  27. Ad-hoc On iseseadistuv võrk, kus seadmed käituvad ruuteritena ning võivad oma asukohta ruumis muuta.

  28. D G C F B E H A MANET X X X

  29. Mobile Ad Hoc Networks • Meaning of the word “Ad hoc” is “for this”, means “for this purpose only”, implies it is a special network for a particular application. • A mobile ad-hoc network (MANET) is a self configuring network of mobile routers (and associated hosts) connected by wireless links—the union of which form an arbitrary topology. • The routers are free to move randomly and organize themselves arbitrarily; thus, the network's wireless topology may change rapidly and unpredictably.

  30. Characteristics and tradeoffs • Characteristics • Decentralized • Self-organized • Self-deployed • Dynamic network topology • Tradeoffs • 􀂄 Bandwidth limited • 􀂄 Multi-hop router needed • 􀂄 Energy consumption problem • 􀂄 Security problem

  31. Adhoc Routing Protocols

  32. Proactive (table-driven) Reactive (on-demand) Hybrid • DSDV • WARP • DREAM • DSR • AODV • TORA • ZRP • HARP Ad Hoc Routing Protocols

  33. Management System Residential Modem BaseStation Business Modem Portable Modem Network Planning

  34. Rahakulu ja katteala

  35. Lingid http://www.cs.umd.edu/~clancy/docs/lwapp-review.pdf http://www.ieee802.org/21/ http://www.ieee802.org/11/ http://www.ietf.org/rfc/rfc3990.txt

  36. Lingid http://en.wikipedia.org/wiki/AODV http://en.wikipedia.org/wiki/Mobile_ad-hoc_network http://moment.cs.ucsb.edu/AODV http://core.it.uu.se/core/index.php/Main_Page

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