1. FlexNET link Connecting The World

2. 2 FlexNET LINK FlexNET LINK Frequency Division Duplex (FDD) – AS.MAX –Communications in one direction are at a different frequency than in the other direction, transmitting and receiving in both directions at the same time Can establish high speeds in both directions (usually equivalent speed) No substantial time delays (latency) for communication, as no information is buffered The difference in frequency can be small (a few MHz) or large (100’s of MHz), in the same frequency band or different bands altogether Time Division Duplex (TDD ) - FlexNET –Communications in one direction are at a different time than in the other direction, transmitting and receiving at the same frequency but in succession Can provide unbalanced communications when desired (e.g. more download than upload, or variable to demand) Has more impact on latency

3. 3 FlexNET Point-to-Point Link Configuration FlexNET Point-to-Point Link Configuration (RN700) Interfaces: –1 x IEEE 802.11a OFDM –1 x Ethernet Outdoor band 5.470 -5.725 or 5.725-5.850GHz Transmit power control (TPC) Dynamic Frequency Selection (DFS) (not in FCC model) Integrated antenna –Gain 20 dBi –Beam width 15 deg Configuration –Bridge mode –Router mode Security –VPN Passthrough, WPA-PSK(AES) –MAC address authentication Management –Web based (HTTP/HTTPS) –Encrypted (SSH2) command-line interface –Multiple administrative classes –SNMP v2c, MIB II Advanced Features –OSPF V2 Routing –Longlink configuration for links up to 25KM –Up and Down Bandwidth shaping per RN700 5.4/5.8GHz Link

4. 4 FlexNET: Link Repeater Configuration FlexNET: Link Repeater Configuration (RN800 or RN900 RN700 may be slaves to RN800 or 900) Interface: –2 x IEEE 802.11a OFDM –2 x Ethernet Outdoor band 5.470 -5.725 or 5.725-5.850 GHz Transmit power control (TPC) Dynamic Frequency Selection (DFS) External antennas –two N-connectors Configuration –Bridge mode –Router mode Security –VPN Passthrough, WPA-PSK(AES) –MAC address authentication Management –Web based (HTTP/HTTPS) –Encrypted (SSH2) command-line interface –Multiple administrative classes –SNMP v2c, MIB II Advance Features –OSPF V2 Routing –Longlink configuration for links up to 25KM 5.4/5.8GHz Link Repeater 5.4/5.8GHz Link

5. 5 Link deployment models Versatile link deployments: –Wireless bridges –Routed links, OSPFv2 dynamic routing based redundant & balanced links... 2* FlexNET, low cost link product FlexNET can also be used as enterprise/high-end 5 GHz CPE pt-pt router1 router2 4 * FlexNET units configured as redundant and load balancing wireless backhaul with external routers running also OSPF 2* FlexNET units with Dual Link configuration with 2* 54 Mbps capacity (LACP device required for L2 or OSPF for L3)

6. 6 Theoretical link ranges

7. 7 What Governs Distance or Coverage? The radio’s technology (sometimes) The “strength” of the transmitted signal The radio’s ‘threshold’ specifications The radio’s frequency of operation Output power regulations Obstacles between the end points Climate/Terrain The antenna pattern

8. 8 Outdoor Wireless Systems Require Engineering Determine Line-of-Sight and Path Clearance –Including Fresnel Zone, k-factor Determine Antenna System Requirements –You need to meet distance fade margin requirements Determine All Cable Types and Lengths Analyze Interference Potential –Including any self-interference Plan for Proper Grounding and Lightning Protection Plan for Egress of Cables from Outdoor to Indoor These statements are true for ANY deployment, even across a parking lot!

9. 9 The Concept of Line-of-Sight (LOS) No obstructions between each end –No trees –No buildings –No mountains Can you go through a window? –Probably, but with added losses that are hard to predict: –Plan on 10dB as an initial guess, can be greater for reflective (metallic) tinted glass Note: The lower the frequency, the better it will travel through obstacles

10. 10 Antennas Outdoor systems usually implement directional antennas –Highly directional (narrow beamwidths) for PTP systems, eg. HiperLink –‘Sector’ (wide beamwidths) for the central location of PMP systems eg. Hyperaccess The choice of gain and beamwidth is critical to the application –The larger the antenna (in surface area), the higher the gain –The lower the gain, the wider the beamwidth –The wider the beamwidth, the more susceptible to interference –The higher the gain, the further the distance and/or improved RSL The configuration of polarization is important to the system plan –To optimize communications, both ends of a wireless system should be implemented with the same polarization

11. 11 Climate and Terrain effects Humid climate is worst –More moisture = more ducting and refraction = more attenuation Dry climate is best –Reduced moisture = less ducting and refraction = less attenuation Mountainous terrain is best –Many multipath reflections will not reach the other end, thus reducing the potential for out-of-phase reflected signals that may have degraded the integrity of the direct signal Flat, smooth terrain is worst –Many multipath reflections may reach the other end, thus increasing the potential for out-of-phase reflected signals that may degrade the integrity of the direct signal

12. 12 Basic distance planning Its Just a series of plus’s and minus’s Transmission Cable (Loss) Antenna (Gain) Radio (Threshold) Transmission Cable(Loss) Antenna (Gain) Path (Loss) Radio (Output Power) RSL Output Power Threshold System Gain Received Signal Level (RSL) Fade Margin Calculator

13. 13 OSPF OSPF software implemented in 1.10.x SW and forward What is OSPF ? - OSPF is a link-state routing protocol based on open standards. Why OSPF ? - OSPF is a powerful, scalable routing protocol. How can it help me Cost-based routing metrics - Unlike RIP, OSPF supports descriptive metrics to indicate the bandwidth and capability of each individual network link. Multi-path routing - OSPF is able to support multiple routing paths to a given destination, giving routers a choice in deciding on the best route to balance data over multiple paths. Dijkstra Shortest Path First algorithm - This fundamental capability of OSPF allows it to calculate a cost to every destination in the network. High level of security - OSPF supports authentication mechanisms to validate router participation in the network.

14. 14 Delivering Self-Healing and Dynamic Rerouting to Networks All possible paths are calculated –Allows change if new route is needed One route or up to 4 equal cost routes may be used. Best path continuously determined based on Media type, Hello Packets, and other OSPF parameters Backhaul Possible Paths Actual Route

15. 15 LAN or WLAN AREA Primary and Backup ISP Higher Metric to ISP 2 (Backup) The Diagram depicts a LAN or WAN using 4 RN800’s, to give access to two ISP’s from the LAN or WLAN area. The Scenario allows for load balancing or using one ISP as backup like we have done. ISP 2 POP ISP 1 POP Operators who have multiple connections to the Internet may Load balance or use one connection as a backup should the primary and preferred connection go down. RN800

16. 16 OSPF Configuration This is not an OSPF course, read the OSPF routing manual for more information. However a few key points to remember - All Areas must connect to the backbone area 0, in certain circumstances a virtual link may be used. Timers may need adjustment for quicker convergance times - The timers spf command will change the hold dowm timer - Dead interval time

17. 17 Example

18. 18 Example Configuration