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HelsinkiOpen.net. Helsingin Alueverkkoyhdistys (ry) Petri Krohn. Helsingin Alueverkkoyhdistys. Helsingin Alueverkkoyhdistys = Helsinki Neighborhood Networking Association “Fiber-optic Community Networking” Grass root activity to build access networks
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HelsinkiOpen.net Helsingin Alueverkkoyhdistys (ry) Petri Krohn
Helsingin Alueverkkoyhdistys • Helsingin Alueverkkoyhdistys = Helsinki Neighborhood Networking Association • “Fiber-optic Community Networking” • Grass root activity to build access networks • Membership open to individuals and businesses • Terminology • Alueverkko = Neighborhood Area Network, Residential Access Network • Seutuverkko = Regional Network • Taloverkko, taloyhtiöverkko = house network? • Asunto-osakeyhtiö = Housing Co-operative • Kunnallinen vuokra-asunto = Council Housing • Pysäköintiyhtiö, palveluyhtiö = Parking & Services Co-op • Kimppaliittymä = Subscriber co-operative
HelsinkiOpen • HelsinkiOpen • "Open access" residential access network • Open.net business model • Start of in two Helsinki neighborhoods, Ruoholahti and Pikku-Huopalahti • Both neighborhoods built in 1990’s. • Homogenous construction • Cat5 cabling missing • Activities focused on building "house networks" in housing co-operatives • Co-operation with area parking & services co-ops • Use of underground parking facilities for right-of-way • Status August 2004: 500 apartments wired • Goal for Aug 2005 5000 apartments connected to Ethernet • Most connected to neighborhood area network
Neighborhood Area Network • Residential access network • Near by buildings connected with short links • Open Access network • Not an ISP but an Ethernet Service Provider (ESP) • Open to all Internet service providers • Equally open to all Internet users in area • Residential • Commercial • Businesses • Subscribers of network • Housing co-operatives • Council housing & other rental property • Businesses • Schools? • Users need not be directly connected • A NAPT router can serve individual buildings, one IP address shared by many users • Service is paid by subscriber co-op (usually same as housing co-op)
Technologies • Ethernet everywhere • Copper, fiber, WLAN, VDSL • Layer 2 transparency • Initially apartments connected through NAPT router • Techniques for connecting buildings • Fiber • dug in • in conduit leased from operator • 802.11 WLAN-links • VDSL in leased lines • Two very different roles for 802.11 wireless technology • Open access points • Point-to-point links to connect separate parts of Ethernet network • Ring topology • Multi-mode fiber (cheap hardware)
Zero-Budget Solutions • Ethernet is cheap! • Hardware US $0,50 / user port • Housing co-operatives: • Investments of up to 200 euros / apartment acceptable • Council housing: • “Pay for your own electricity!” • Digital Divide • Greatest need for services on places with poorest infrastructure
Cabling Solutions Commercialized: • New Cat5e cable in old conduits, leave phone wires untouched • Cost of installation: 100 - 200 euros / apartment • 10Base-T + POTS in 3-pair twisted pair telephone cable • Suitable cable found in all post 1995 construction + post 1980 row-houses • VMOHBU/MHS 3 x 2 x 0,5 Experimental: • 10Base-T + POTS in 2-pair twisted star-quad telephone cable • (MHS 1 x 4 x 0,5) • EtherSPLIT (US patent pending) • Normal DSL-filters can be used to separate Ethernet and voice Future trend? • Abandon fixed line telephone (POTS/ISDN) • Use existing 2-pair cable for 10Base-T Ethernet • Utilize VoIP services for fixed telephony • 2004: only 2/3 of apartments have fixed telephone connections
Problems • Cost of local communication network • 90% right-of-way • 9% cable and fiber • 1% Switches and other active hardware • Need critical mass • Heterogeneous ownership structure • Resident owned housing co-operatives • Council housing • Other rental apartment blocks (SATO, VVO, Insurance companies) • Getting rental landlords and council housing involved
Model for Free Wireless Service • Peer-to-peer (P2P) users create an increase in available bandwidth • Wireless users need very little bandwidth • => Bandwidth is available (for free) • Greatest obstacle to opening access points is security • Urban myth has spammers roaming around looking for open access to exploit • Free service needs authentication, can use any locally available ISP • Radius server at radius.helsinkiopen.net • Access control in NAPT router, m0n0wall • “Tax” on ISPs utilizing open access network: • 10% of bandwidth must be donated for free services.
Virtual Networks Technologies for separating service providers in an open access network
Parallel Trends • Network Virtualization • Open Access Networks • Same technology • Different motives
Network Virtualization • One central device for • Access control • Authentication • firewall • bandwidth throttling • NAT • Routing • Traffic shaping • … • Users are connected through virtual networks • Examples (Finnish ISPs) • Saunalahti Freedom (VPN) • Sonera kiinteistö (PPPoE) • Campus networks
Technologies for Virtual Networks • Layer 3 • Requires private IP address space (10.0.0.0) + routing • Virtual Private Networks • Point to Point Tunneling Protocol (Microsoft) • IP Security (IPSec) IETF • Layer 2 • Requires transparent L2 network • Virtual LANs • IEEE 802.1Q tags • Mapping of VLANs to SSID names in access points • 802.1X access control • Point to Point Protocol over Ethernet (PPPoE) • authentication & encryption • Layer 2 Tunneling Protocol (L2TP) • authentication & encryption
Which Technology to Choose? • Which virtual networking technology should an open access network operator choose to deploy? • The choice is for the service provider to make, not the access network • All technologies can be deployed simultaneously • Requirements for Open Access Networks • Service providers must be able to build virtual networks with the technology of their choose • Layer 2 transparency • IP routing for private network addresses
Layer 2 transparency • 802.1Q VLAN tags • QoS (802.1p) • Ethernet multicast • Q-in-Q? • Needed in metro-scale open access networks & ESP business • Not needed in residential access networks
Open Questions • Telecommunications: service or infrastructure? • VPN or PPPoE or 802.1Q? (Or neither?) • Individual subscriptions with IP or collective subscriptions with NAPT? • Wireless access: pay for bandwidth or provide authentication?