Ozone's Presentation to EU-Mesh

Ozone presentation

French Wireless ISP Founded in 2004... Goal : allow “Everywhere, EveryTime, Cheap and Effective

connectivity” and build a pervasive network Wifi was at that time the obvious choice for developing the network

(cheap, widespread, flexible, no licence) but Ozone is fundamentaly technology agnostic

...and bought in 2007 by Neuf Cegetel Neuf Cegetel is the French second major Telco and ISP 3000 employees Counts with 4M DSL clients (retail) Important market share in Business clients …To be bought by SFR, second French mobile Operator, within

weeks…

Network logic (1)

Antennas on rooftops to provide a local coverage We don’t pay for accessing rooftops : we gain access through

individuals “offering” their rooftop in exchange of free access to our services

They also power the installation (~20 W) 5 Radio cards on each roof :

3 * 2.4 GHz (=3 * 120 °) for clients connections 2 * 5 GHz for backhauling functions

Multiply roofs to offer a full coverage of the city About 1000 roofs to provide a first mapping of the city (105 km²) / Each

roof covering ~ 200m radius circle Full coverage provided through additional deployments (Urban furniture,

lamposts…) Backhaul roofs with efficient and affordable

technology Provide symmetrical Throughput

At least 8 Mb/s on each roof Mainly Wireless Point to Multipoint using 5GHz (802.11a)

Free licences, good throughput, cheap hardware Needs Line Of Sight (LOS) between roof and Concentration sector

…but also ADSL, Fiber, Wimax (when no LOS)

Network logic (2)

Each roof is connected to a concentration sector Through a 5GHz link based on 802.11a

A concentration sector is a sector antenna connecting up to 8 roofs

About 25 Mb/s IP available at each sector antenna to dispatch among roofs

Concentrations sectors are located on high buildings in Paris

9 of these building today Each building connected to the internet through fiber

Up to 20 concentrations sectors per building Limited by frequency reusability

Each roof might connect another roof itself Handy for sites that don’t have LOS to Concentration points

Clients

3 plans 18 € for unlimited monthly access

About 2500 clients each month 7,8 € for a daily pass

About 1000 clients 1,5 € for a 1 hour pass

About 6500 clients

About 10K users more at partners sites Deal : indoor coverage and free internet access in exchange of roof

access Museums

- Palais de Tokyo- Museum of Modern Art Centre Pompidou

Hospitals, Firms, associations

250 roofs

Today’s network (01/2008)

Concentration Sector

roofs

Roof with no LOS

Concentration Sector focus

RSSI :

RSSI > -70 dBm

On both side.

DSL as backhaul

Standard DSL link used Up to 20 Mb/s DL | 1 Mb/s upload

Tunnels used to hide the DSL layer Allows to monitor transparently the roof connected The user has no knowledge he is using a DSL link

A typical roof (1)

Omni-directionnal Antenna (5GHz)

Sector Antennas (2.4 GHz)

Directionnal Antenna (5GHz)

Outdoor Case

A typical roof (2)

Concentration sectors

Sector Antennas (5 GHz)

Directionnal Antennas (5GHz)

Hardware

Mikrotik Boards RB532A (discontinued now)

MIPS architecture 64 MB SDRAM 3 Mini-PCI slots ~50 % CPU load on concentration sector with high throuput (~15-20 Mb/s)

RB600 PPC architecture (400 MHz) 64MB SDRAM 4 Mini-PCI

« daughter boards » plugged to main board To add Mini-PCI slots and reach 5 Wifi cards per roof

Wifi Cards Atheros chipsets (AR5213 baseband / AR5112 RoC) 802.11 a/b/g Tests ongoing on 802.11n

Seems especially interesting for enhancing coverage in Ozone’s case

Antennas 2.4 GHz sectors (120°) 5 GHz sectors / directionnals / omnidirectionnals

Software

Mikrotik RouterOS Handles Point to Multipoint topology nicely

Important in our Backbone to avoid the « hidden node » problem No Open source philosophy here

A problem to integrate innovative solution

OpenWRT On roof using DSL as a backhaul link

OpenVPN not well implemented on RouterOS

At the IP Level

All the network is routed OSPF in the backbone

Up to concentration sectors Then static routing

BGP peering with Tier 1/2 provider FreeBSD server running bgpd and ospfd

QoS introduced Assuming each roof has 8 Mb/s, traffic prioritization

Snmp, ssh DNS, small packets (ACK), SIP Web, mail Other traffic P2P

Problem is we don’t know actually what throughput is available at a given time on the wireless backhaul link

Authentification Radius & MySQL databases

FreeRadius used Proxy services offered to partners (T-Mobile, Neuf Cegetel…)

Operations / Management

Deployment Made through Third parties contractors which have limited but

necessary knowledge of the network Implies they have a PC while deploying to verify antennas orientation,

radio association, etc…

Monitoring and maintenance SNMP Through Open Source softwares

Nagios for Network surveillance, availability reports, network instant trends

Cacti for graphing

Own developped tools for mass configuration / maintenance

Services

Services offered Standard internet access

Throughput offered may vary according to the client's connection quality with the infrastructure and overall load ; goal is to provide 2 Mb/s symetrical

Telephony SIP based ; we operate our own SIP proxies and have a PSTN connection

through a business partner- SIP Proxies based on Asterisk and SER

We offer as well SIP transit services to partners (Neuf Cegetel mainly…)

About to launch Geo-localisation services

Through IP based localisation : 200m precise in Ozone’s case Through third party software : cf www.loki.com

“Mobility” services Integrating various backhaul technology transparently for the users

through tunnels- OpenVPN based (transparent to user)- Overhead might be a problem (up to 20% up to now)

Deployment relevant to EU-Mesh

100 lamposts in Paris To be deployed end of May Each lampost will be equiped with a 3 radio AP

1 * 2.4 GHz radio (802.11 b/g(/n)) for clients connectivity 2 * 5 GHz radio (802.11 a) for backhaul

Lampost might be backhauled by 5GHz link (Ozone network) ; majority of them DSL link (directly or through wireless hop) Wimax link

Goal is to provide seamless mobility for clients moving from lamposts to lamposts

In some area, we will deploy APs on up to 10 lamposts 100m distance between each lampost in these areas Mobility will be checked with Surf and VoIP

- Either through tunnels, or WDS

In the same area, different backhaul solution might be adopted simultaneously

Lampost deployment

5GHz 5GHz 5GHz 5GHz 5GHz

PoE PoE PoE PoE PoE PoE

Ozone

100 m 100 m 100 m

EU-Mesh trials could be done on a portion of this deployment

Comparison of EU-Mesh and standard 802.11 networks

Network flaws (some of them…)

Coverage is still low A way to enhance coverage in a cheap and convenient way would

be very helpfull No Mesh in the network

Deployment could be a lot easier Mesh network implying zero-configuration during installation would be a

great feature for us Auto-reconfiguration on failure would be a very interesting feature

Though our antennas are fixed, we have an Omni-antenna we could benefit from to enhance resilience in the network

Other hardware configuration could be studied and deployed to enhance resilience

- Though major cause for outages in our network is power shortcuts

« Dumb » network Poor QoS settings

Beeing able to locally manage QoS (based on actual Throughput) and have information on a full path (and not only a node) from a QoS point of view would be a very appealing feature

No interferences handling Neither at 2.4 GHz nor at 5 GHz