Shared Internet access in Finnish housing cooperatives

This is part one of a longer post on co-operative network activity in Finland. The Finnish model differs from the way Internet services are provided in most other counties. Information on Finnish co-ops has never before been available in English. Here I have tried to put together all the relevant information and experience.

1 Networking in housing co-ops - HomePNA? 2 Router issues 3 Cabling issues - Ethernet on phone wires 4 Wireless networking

This message has been cross-posted to several newsgroups. General follow-ups to news:comp.networking.connectivity.

*** *** ***

The beginning - Operator-driven networks

The first Finnish in-house networks were built in the late 1990's when construction companies began installing structural cabling in new apartment buildings. An Ethernet LAN was used to provide Internet access to residents.

This brought external service providers in to the in-house network. In this business model the operator (telco) would sell the the service directly to to the resident.

Sometimes the building would be connected to the service providers network by fiber-optic cable. The fiber would be placed at an early stage of construction. The newly formed housing cooperative would pay the full cost of the cabling work as sign-up fees for the Internet service. The agreement between the co-op and ISP would not allow the co-op to buy Internet service. Instead it allowed the ISP to take over the internal wiring and monopolize the network. The service provider was free to price the service as they pleased. The co-op could not abandon the agreement as it meant loosing their large sign-up fees.

This model did bring residents fast Internet access. It did not however bring down the cost of access as the service was always priced at or above the price of slower fixed access alternatives. The monthly fee for fast Ethernet access in these houses is around EUR 50 with little change in sight.

HomePNA

A new technology, HomePNA was introduced to in-house networks by the Internet operator Jippii (now Saunalahti). Originally Home Phoneline Networking (HomePNA) was marketed in the US as a way of building home networks by utilizing the multiple existing phone sockets in the house. In Asia the technology was adapted for ISP use with the introduction HomePNA 1.1 switches.

formatting link
In an in-house HomePNA network a stack of HomePNA switches is placed in the central telephone wiring closet of the building. Each apartment is connected to one port on the switch using the same twisted pair that carries telephone traffic to the apartment.

Internet connectivity is provided by one (or more) ADSL or G.SHDSL connections.

Operator-run HomePNA networks reached their peak popularity by the end of

2003. In that year most landlords owning apartment blocks, including "council housing", made agreements with ISPs to market HomePNA services to tenants at a price of around EUR 35 a month.

The last year has seen a steady decline in popularity of ISP run HomePNA networks.

  1. A sharp decline in ADSL prices and increase in speeds has made HomePNA service uncompetitive against ADSL and cable modem connections starting at EUR 19,50 a month.
  2. The business model is unworkable. An infrastructure like an in-house network needs "monopoly protection", not market competition. In the worst case, one housing cooperative might have two competing HomePNA networks installed in the same wiring closet, both networks providing service to 2 - 3 customers.

Also one problem is that often the operator providing HomePNA service is also providing ADSL service in the same area. These operators are unwilling to push HomePNA prices below ADSL prices.

Cooperative networks

In 2000 housing cooperatives in Finland started building their own HomePNA networks. In this model the housing cooperative would own the networking hardware and pay for the Internet connection.

In early networks only those residents interested in the fixed Internet connection would take part in the costs. A subscription fee was set up and collected monthly by the housing cooperative, along with the maintenance fee and any other extras for services like the weekly sauna or parking space. The cost of hardware and installation was covered by the fee in about two years.

In these early networks about 50% of residents were connected with monthly fees at around EUR 7.

Some of the first networks were set up in the Helsinki neighborhood of Maunula in an government initiated project:

formatting link
Internet access to everyone

Newer networks have adopted a different model. All apartments are connected to the network and Internet service is provided without any extra fee. At a minimum Internet-service can be provided at around EUR 1 per month with around EUR 100 per apartment in initial investment costs.

Not having to connect and disconnect individual apartments greatly eases the maintenance of the network.

In houses with free Internet access network usage has reached a level of 85% of apartments.

The future of HomePNA

With "Full Rate" ADSL connections at 8/1 Mbps becoming available to consumers at a price of EUR 45 and to housing cooperatives at EUR 115 the limited speed (1 Mbps) of HomePNA 1.1 has become a bottleneck. To lock the key "heavy users" to the cooperative network faster speeds must be available. Construction of new HomePNA-based networks now seems to have come to a standstill.

HomePNA 2.0 at 10Mbps proved to be too prone to cross talk so no switches are available. HomePNA 3.0 could provide a speed of 100Mbps but the switches have yet to reach European markets.

At the same time the price of compact ADSL DSLAMs (switches) has dropped to almost the same level as HomePNA switches, at around EUR 50 per subscriber. The problem with ADSL is its ATM foundation, which causes unnecessary configuration issues in an otherwise purely Ethernet-based network. VDSL would provide better Ethernet compatibility and higher speeds, but the standards are immature and hardware is incompatible.

Ethernet would provide the best alternative, but usually the wiring is missing. Finnish housing cooperatives are now facing a tough technical choice between rewiring for Ethernet and adapting ADSL or VDSL technology for in-house networks.

Security

Security in an in-house network requires that users cannot communicate directly through the LAN using local IP-addresses or LAN-protocols. All traffic must pass through a router and be based on public IP-addresses. The technique to achieve this is to use "port isolation" in the Ethernet and HomePNA switches. This feature is available in all switches targeted for the MDU-market.

In-house networks usually share one public IP-address among all users. The NAPT router isolates the house network from the Internet and provides a built in firewall.

Finnish national policy

The Finnish national "Broadband Strategy" emphasizes competition to the detriment of infrastructure. The aim is to utilize the existing coper base of the telephone network to its fullest. In this model each user will have an individual subscription with a profit driven telco.

Virtually no encouragement is given to cooperative networks or even in-house networks.

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The opposition, the "fiber party" is largely concentrated in the Swedish-speaking districts of Ostrobotnia. These people believe in the importance of infrastructure; fiber-optic Ethernet to every house!
formatting link
(in Finnish)

Housing in Finland

Most Finns live in apartment blocks. Finland has the second highest percentage of apartments in Europe after Spain. Also, a large proportion of Finns own their apartments. Most apartment houses are organized as housing cooperatives. The first housing cooperatives were built in Finland around

1900.

Some of the first Finnish Housing cooperatives are located in the Katajanokka neighborhood in Helsinki: -

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-
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Finnish writers often translate the Finnish word "asunto-osakeyhtiö" as "housing company". The term "housing cooperative" is more accurate as the form of incorporation of Finnish cooperatives is identical with those in the US. In fact, the housing cooperative model was brought to the United States by Finnish immigrants.

"The first true cooperative development in the United States was started in 1918 by a group of Finnish artisans-the Finnish Home Building Association in Brooklyn, New York. " -

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-
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*** *** Vocabulary

Housing cooperative "Housing cooperatives are a form of homeownership where individuals own shares or memberships in a corporation that owns or controls the land and buildings that provide housing. The ownership of a share entitles one to occupy a unit within the cooperative."

formatting link
Council housing (British term) Social housing owned by the city or municipality.

MDU Multi-Dwelling Unit

In-house network A LAN connecting apartments in an apartment block and providing Internet access

Internet connection sharing In English parlance "connection sharing" is often used to refer to sharing your Internet connection between multiple computers. In this text it refers to sharing one WAN connection and possibly one IPv4 address between multiple subscribers.

Operator In the US often referred to as "carrier". A large telco offering telephone and ISP services.

Euro (EUR) The European Currency Unit, now rated at about US $1.32 to one Euro.

Reply to
Petri Krohn
Loading thread data ...
[Part 2: Router issues]

Bandwidth-sharing problems

Early HomePNA networks suffered from bandwidth-sharing problems. In an shared Internet connection bandwidth usage between different users may differ by over one thousand fold. The heaviest traffic is caused by file sharing and other p2p-programs.

Without any bandwidth limitations or priorization two or even one BitTorrent user can disable a network and block net access to all neighbors. In an asymmetric ADSL-connection saturation of the uplink will cause the free capacity of the downlink to become unusable. Network latency (ping) grows to over 1 second, practically freezing all other traffic.

ISP:s and housing cooperatives took very different approaches to solving the problem:

In ISP-run networks the built in bandwidth limitation features of HomePNA switches were taken into use. Per user bandwidth was throttled down to a minuscule 128 or 256 kbps.

Cooperative networks wanted to provide each user the full capacity of the network. Artificial restrictions were disliked. The solution was user education. Network activists would monitor network traffic, advise neighbors on proper usage of p2p-software and even temporarily disconnect users who failed to follow the guidance.

Technical solutions

Luckily purely technical solutions have become available to the bandwidth sharing problem in the form of traffic shapers. One useful alternative is the FreeBSD-based firewall distribution m0n0wall with an easily configurable traffic shaper:

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A Finnish company, Staselog also produces a traffic shaper for cooperative in-house networks:
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Functions of a traffic shaper: 1.Delay outgoing traffic so the uplink is newer saturated. 2.Prioritize interactive traffic. 3.Recognize p2p-traffic and set to lowest priority. 4.Give each user an equal share of the usable bandwidth.

Routing with one public IP address

A shared Internet connection will typically use only one public IPv4 address. A router has to perform Network Address Port Translation (NAPT) between the internal network and the Internet. Normally NAPT blocks all users from running servers on their PC:s. This is a problem for p2p applications and may block VoIP services altogether.

A solution is to open a fixed set of port mappings in the router. A set of ports is allocated for each apartment. Also a set of fixed private addresses is allocated for each apartment.

Normal users use DHCP to get their IP addresses in the private network. If a user wants to run a server or a p2p program in active mode, he configures his PC to use his fixed private address. The set of open ports will be mapped to this address.

Example: - address 10.10.10.157 is reserved for apartment 157 - ports 51570 - 51579 are mapped to address 10.10.10.157 in the private network.

A general configuration of the router can be made that can serve any shared residential network. When using m0m0wall this configuration takes the form of an XML file that can easily be distributed. (Hope to make this available after some more editing :-)

(Follow-ups to news:alt.comp.networking.connectivity.)

Reply to
Petri Krohn
[Part 2: Router issues]

Bandwidth-sharing problems

Early HomePNA networks suffered from bandwidth-sharing problems. In an shared Internet connection bandwidth usage between different users may differ by over one thousand fold. The heaviest traffic is caused by file sharing and other p2p-programs.

Without any bandwidth limitations or priorization two or even one BitTorrent user can disable a network and block net access to all neighbors. In an asymmetric ADSL-connection saturation of the uplink will cause the free capacity of the downlink to become unusable. Network latency (ping) grows to over 1 second, practically freezing all other traffic.

ISP:s and housing cooperatives took very different approaches to solving the problem:

In ISP-run networks the built in bandwidth limitation features of HomePNA switches were taken into use. Per user bandwidth was throttled down to a minuscule 128 or 256 kbps.

Cooperative networks wanted to provide each user the full capacity of the network. Artificial restrictions were disliked. The solution was user education. Network activists would monitor network traffic, advise neighbors on proper usage of p2p-software and even temporarily disconnect users who failed to follow the guidance.

Technical solutions

Luckily purely technical solutions have become available to the bandwidth sharing problem in the form of traffic shapers. One useful alternative is the FreeBSD-based firewall distribution m0n0wall with an easily configurable traffic shaper:

formatting link
A Finnish company, Staselog also produces a traffic shaper for cooperative in-house networks:
formatting link
Functions of a traffic shaper: 1.Delay outgoing traffic so the uplink is newer saturated. 2.Prioritize interactive traffic. 3.Recognize p2p-traffic and set to lowest priority. 4.Give each user an equal share of the usable bandwidth.

Routing with one public IP address

A shared Internet connection will typically use only one public IPv4 address. A router has to perform Network Address Port Translation (NAPT) between the internal network and the Internet. Normally NAPT blocks all users from running servers on their PC:s. This is a problem for p2p applications and may block VoIP services altogether.

A solution is to open a fixed set of port mappings in the router. A set of ports is allocated for each apartment. Also a set of fixed private addresses is allocated for each apartment.

Normal users use DHCP to get their IP addresses in the private network. If a user wants to run a server or a p2p program in active mode, he configures his PC to use his fixed private address. The set of open ports will be mapped to this address.

Example: - address 10.10.10.157 is reserved for apartment 157 - ports 51570 - 51579 are mapped to address 10.10.10.157 in the private network.

A general configuration of the router can be made that can serve any shared residential network. When using m0m0wall this configuration takes the form of an XML file that can easily be distributed. (Hope to make this available after some more editing :-)

Reply to
Petri Krohn
[Part 3 Cabling issues - Ethernet on phone wires]

"Helsingin Alueverkkoyhdistys" (Helsinki Neighborhood Networking Association) is a group of local volunteers and activists with the altruistic aim of providing "free"¹ Internet access to everyone.

The ultimate goal is to build community owned fiber-optic networks in residential neighborhoods. Equally important is an open network of wireless access points. We believe that universal free and open WLAN access is only possible, if its backed up by an solid infrastructure of shared wired networks.

The first stage is to build in-house networks in the apartment blocks and housing cooperatives. Only when we reach a critical mass of in-house networks can we start connecting them into neighborhood networks. Housing cooperatives are important also in the sense that they can easily be persuaded to give away the free bandwidth needed for the open wireless coverage.

¹ Free in this case means free as in "free lunch"; there is no such thing. Someone will have to pay for the service, or better yet build the infrastructure that provides the service. The idea is to make Internet access a basic infrastructure like streets, electric lighting and running water, available to everyone in need of it. This infrastructure should be provided by the same people who provide these basic services, in most cases the property owners.

Activity has been greatest in two new Helsinki neighborhoods, Ruoholahti and Pikku-Huopalahti. These neighborhoods consist of prefabricated concrete apartment blocks built mainly in the early 1990's with anywhere between 30 and 170 apartments each. -

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Ethernet everywhere!

From the start the aim has been for higher speeds, thus the focus on Ethernet technology.

It was felt that if the slow but popular HomePNA technology would be used for in-house networks, it be a serious hindrance to fiber-optic neighborhood networks. The limited bandwidth that can be delivered by HomePNA can always be served by ADSL or other technologies over coper.

Also the focus has been on finding cheap or "zero-cost" solutions for Ethernet. Housing cooperatives may be willing to invest more heavily, but in Helsinki all new neighborhoods are mixed neighborhoods with both resident-owned co-ops and city-owned social housing. The technical solutions should be so cheap that they can be adopted by council houses with very limited budgets.

Add-on cabling

The standard way of rewiring houses in Finland has been to use diamond drills to pierce floors and walls. Heavy-duty aluminum profile conduits are installed in stairwells to house new cabling. In apartment buildings this effort was only taken up in conjunction with other renovations, like renewing the electrical wiring.

Rewiring for the sake of Internet access had not taken up. The only residential buildings where the effort was made where student dormitories. The costs would be around 400 euros per apartment. We started looking for cheaper, lighter alternatives.

Telephone and central antenna cables to apartments are typically enclosed in

20 mm plastic tubing. This would leave space for an other cable in the same conduit. Also, there should be no need to remove existing telephone wire to provide the additional Ethernet access.

Initially there was a great distrust that new wire could be pulled alongside in the same conduit. The only reference was an undocumented 1995 effort to rewire the dormitories of the Helsinki University of Technology with Cat-5 cable. This was done by student volunteers.

The first houses were rewired in 2003 by volunteer residents. When it was established that the technique can be utilized, this approach was also taken up by a large wiring contractor. Several houses with hundreds of apartments have been wired with a 100% success rate.

Inside the apartment the Finnish legacy telephone socket in one room is replaced with a new faceplate with RJ11 and RJ45 connectors. The cost estimate for this type of "add-on" wiring is about ? 150 per apartment. Success requires that the original construction is up to standard.

Horizontal access

Horizontal telephone cabling in Finnish houses is often done with direct burial cable. There is no horizontal conduit connecting the splices in different stairwells. Even worse, a housing cooperative might consist of several detached buildings separated by an asphalt covered courtyard.

In a prototype house fiber-optic cable was used to connect the Ethernet-switches in the different buildings. Volunteer residents dug up a ditch for the underground conduit connecting the buildings. Later experience has shown this effort to be unnecessary; Finnish telephone cable has proven its ability to carry 100Base-TX Ethernet for over a hundred meters.

The structure for the in-house Ethernet network in a large apartment block:

  1. Place one 24-port Ethernet switch near each stairwell, preferably in the electricity or central antenna closet. Usually the Scotchlok splice for the telephone wiring is located in this same space. 2. Pull new Cat-5e cables from the closet to each apartment. 3. Use free pairs in the direct burial telephone cable to connect the Ethernet switch to the central telephone wiring closet at 100 Mbps. 4. Place the router and central switch at the telephone wiring closet.

Using Cat-3 telephone cable

New Finnish houses built after the year 2000 usually have structural cabling, that is separate Cat-5e cables for Ethernet and telephone with RJ-45 connectors. Older houses houses only have cabling for telephone. Although it is not widely publicized, Finnish telephone cable from the

1990's has a Cat-3 rating.

Houses built after 1995 usually have three twisted pairs serving each apartment. It has turned out to be quite a simple task to convert the cabling to Ethernet use. Originally Finnish legacy telephone sockets are installed with only one pair connected. This leaves two pairs free for use by Ethernet. The transformation consists of exchanging one legacy socket for a RJ-11 / RJ-45 combination faceplate and resplicing the Ethernet-pairs so that only one socket is connected.

The biggest problem for high speed traffic is the Scotchlok splices used to connect different parts of the telephone cabling. These are not made to Cat-3 standards. Practical tests however have shown the connections not to be a problem. Most installations have worked flawlessly even at higher speeds of 100 Mbps.

Distances over 100 meters do not seem to pose a problem either. Zero error operation has been observed in telephone cable at - 100 Mbps for over 100 meters - 10 Mbps for over 150 meters

The trick in running 100Base-TX over Cat-3 telephone cable is to only run one Ethernet link in one cable. This way cross talk between pairs is minimized.

Giving up fixed-line telephone

Houses built before 1994 usually only have two pairs, in the form of a twisted star quad, serving each apartment. Using these pairs for Ethernet traffic poses two problems:

  1. Star quad has an impedance of 120 ohms, which differs from the twisted pair impedance of 100 ohms.
  2. Using both pairs for Ethernet means that the resident would have to give up fixed line telephone service.

In practical tests the impedance mismatch between the pull to the apartment and the multi-paired trunk cable has shown not to be a problem. 10Base-T works reliably.

Giving up the fixed phone may not be a problem. Most voice has already "gone mobile" i.e. moved to mobile phones. The remaining fixed voice traffic is fast moving to VoIP over the Internet. New programs like Skype and VoIP gateway service to consumers has made this move possible.

In a survey of residents in a potential conversion site 83% of residents wanted fixed Internet access. Only 45% required fixed telephone service. This means that over half of the apartments could be converted to Ethernet with about 30% needing ADSL or VDSL service.

Filtered solutions for POTS + Ethernet

It may also be possible to run POTS and Ethernet simultaneously on the same two twisted pairs. Ethernet would occupy the higher frequency band over POTS on the same pair. Splitters or filters would be used in each end to separate the two types of traffic.

A company in the US, Energy Transformation Systems, makes filters for this purpose.

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A Finnish company H.Vesala Ltd. also makes a similar filter, although for ADSL use.
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A slightly different implementation is provided by etherSPLIT.
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(Follow-ups to news:comp.dcom.cabling and news:comp.dcom.lans.ethernet.)

Reply to
Petri Krohn
[Part 4: Wireless networking]

Free wireless access

One of the ultimate goals of this co-operative networking activity is to cover neighborhoods with a "cloud" of free wireless Internet access.

Wireless WLAN networks should not be seen as a primary means of net access, but as an alternative and additional form of access, more like the ultimate icing on the cake.

Giving out free bandwidth requires a fixed backbone with bandwidth to spare. Also the networks need to be based on a culture of sharing.

In the Helsinki wireless "model" open wireless access will be provided by housing cooperatives. Access points are placed in elevator machine rooms with strong sectoral antennas placed on the roofs. In concrete buildings it is difficult to cover the apartments from with in the building but a directional antenna can easily reach neighboring apartments through windows.

Full coverage requires thus cooperation between neighbors. In an reciprocal agreement neighbors can grant each other access to their networks. The practical solution goes even further. A central registry of co-op residents is maintained in a Radius server (radius.helsinkiopen.net). All housing cooperatives share this database for access control. The added value is the ability to freely roam inside and between neighborhoods. Roaming agreements between other networks will further expand the area of movement.

Giving free and uncontrolled access to everybody might seen like an even better idea. This is a much more difficult concept to sell to co-op management boards. The chief concern is not bandwidth usage but security. Network operators want to be able control who uses their network and to keep out spammers and an abusers.

To gain access it is thus not necessary to be a member of an organization giving reciprocal service. It may be sufficient to be a member of an organization who will authenticate you. In the Oulu public access wireless network everyone who is a customer of the public library can gain access to the free network.

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The technical implementation of access control can also be done with the m0n0wall firewall. M0n0wall has a built in captive portal that connects to an external Radius server.

VoIP roaming with DECT handsets

(This an idea for future developement.)

It would be highly useful if VoIP based telephony service could be provided to roaming wireless users. The radio access network should be free of any charge for all authenticated users. (The users would of cause pay their VoIP gateway operator for any calls they make to fixed phone lines.

WLAN based VoIP handsets have been expected on the market for several years now. It now seems that WLAN may not be the right technology for mobile VoIP services after all. A far maturer technology is DECT (Digital Enhanced Cordless Telecommunications). These cordless phone products have been on the market for over 10 years with cheapest handset + base station sets available for under 30 euros.

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The DECT Radio or "air" interface provides roaming capabilities similar to the GSM network. DECT roaming is in fact limited by the tie up of DECT handsets to individual base stations.

For true roaming to be enabled the base stations need a complete redesigned.

  1. POTS connectivity replaced by Ethernet/IP-connectivity. 2. Authentication of handset moved to central authentication server or Radius server. 3. DECT roaming mapped to some IP-based roaming scheme, possible mobile IP.

The North American counterpart of DECT, "Personal Wireless Telecommunications" or PWT newer got of the ground. Instead a DSS based system operating at 2.4GHz has gained popularity.

Building combined 2.4GHz WLAN + cordless phone base station might be easier in the US as one antenna might be used to serve both networks. However, the price of 2.4GHz handsets far exceeds the price of DECT handsets. 2.4GHz cordless handsets may not be competitive against true WLAN + VoIP handsets.

(Follow-ups to news:alt.internet.wireless.)

Reply to
Petri Krohn

This is part one of a longer post on co-operative network activity in Finland. The Finnish model differs from the way Internet services are provided in most other counties. Information on Finnish co-ops has never before been available in English. Here I have tried to put together all the relevant information and experience.

1 Networking in housing co-ops - HomePNA? 2 Router issues 3 Cabling issues - Ethernet on phone wires 4 Wireless networking

This message has been cross-posted to several newsgroups. General follow-ups to news:comp.networking.connectivity.

[I am sorry for the repost. My ISP's news server crashed and failed to deliver anything. Cancels have been issued on the originals.]

*** *** ***

The beginning - Operator-driven networks

The first Finnish in-house networks were built in the late 1990's when construction companies began installing structural cabling in new apartment buildings. An Ethernet LAN was used to provide Internet access to residents.

This brought external service providers in to the in-house network. In this business model the operator (telco) would sell the the service directly to to the resident.

Sometimes the building would be connected to the service providers network by fiber-optic cable. The fiber would be placed at an early stage of construction. The newly formed housing cooperative would pay the full cost of the cabling work as sign-up fees for the Internet service. The agreement between the co-op and ISP would not allow the co-op to buy Internet service. Instead it allowed the ISP to take over the internal wiring and monopolize the network. The service provider was free to price the service as they pleased. The co-op could not abandon the agreement as it meant loosing their large sign-up fees.

This model did bring residents fast Internet access. It did not however bring down the cost of access as the service was always priced at or above the price of slower fixed access alternatives. The monthly fee for fast Ethernet access in these houses is around EUR 50 with little change in sight.

HomePNA

A new technology, HomePNA was introduced to in-house networks by the Internet operator Jippii (now Saunalahti). Originally Home Phoneline Networking (HomePNA) was marketed in the US as a way of building home networks by utilizing the multiple existing phone sockets in the house. In Asia the technology was adapted for ISP use with the introduction HomePNA 1.1 switches.

formatting link
In an in-house HomePNA network a stack of HomePNA switches is placed in the central telephone wiring closet of the building. Each apartment is connected to one port on the switch using the same twisted pair that carries telephone traffic to the apartment.

Internet connectivity is provided by one (or more) ADSL or G.SHDSL connections.

Operator-run HomePNA networks reached their peak popularity by the end of

2003. In that year most landlords owning apartment blocks, including "council housing", made agreements with ISPs to market HomePNA services to tenants at a price of around EUR 35 a month.

The last year has seen a steady decline in popularity of ISP run HomePNA networks.

  1. A sharp decline in ADSL prices and increase in speeds has made HomePNA service uncompetitive against ADSL and cable modem connections starting at EUR 19,50 a month.
  2. The business model is unworkable. An infrastructure like an in-house network needs "monopoly protection", not market competition. In the worst case, one housing cooperative might have two competing HomePNA networks installed in the same wiring closet, both networks providing service to 2 - 3 customers.

Also one problem is that often the operator providing HomePNA service is also providing ADSL service in the same area. These operators are unwilling to push HomePNA prices below ADSL prices.

Cooperative networks

In 2000 housing cooperatives in Finland started building their own HomePNA networks. In this model the housing cooperative would own the networking hardware and pay for the Internet connection.

In early networks only those residents interested in the fixed Internet connection would take part in the costs. A subscription fee was set up and collected monthly by the housing cooperative, along with the maintenance fee and any other extras for services like the weekly sauna or parking space. The cost of hardware and installation was covered by the fee in about two years.

In these early networks about 50% of residents were connected with monthly fees at around EUR 7.

Some of the first networks were set up in the Helsinki neighborhood of Maunula in an government initiated project:

formatting link
Internet access to everyone

Newer networks have adopted a different model. All apartments are connected to the network and Internet service is provided without any extra fee. At a minimum Internet-service can be provided at around EUR 1 per month with around EUR 100 per apartment in initial investment costs.

Not having to connect and disconnect individual apartments greatly eases the maintenance of the network.

In houses with free Internet access network usage has reached a level of 85% of apartments.

The future of HomePNA

With "Full Rate" ADSL connections at 8/1 Mbps becoming available to consumers at a price of EUR 45 and to housing cooperatives at EUR 115 the limited speed (1 Mbps) of HomePNA 1.1 has become a bottleneck. To lock the key "heavy users" to the cooperative network faster speeds must be available. Construction of new HomePNA-based networks now seems to have come to a standstill.

HomePNA 2.0 at 10Mbps proved to be too prone to cross talk so no switches are available. HomePNA 3.0 could provide a speed of 100Mbps but the switches have yet to reach European markets.

At the same time the price of compact ADSL DSLAMs (switches) has dropped to almost the same level as HomePNA switches, at around EUR 50 per subscriber. The problem with ADSL is its ATM foundation, which causes unnecessary configuration issues in an otherwise purely Ethernet-based network. VDSL would provide better Ethernet compatibility and higher speeds, but the standards are immature and hardware is incompatible.

Ethernet would provide the best alternative, but usually the wiring is missing. Finnish housing cooperatives are now facing a tough technical choice between rewiring for Ethernet and adapting ADSL or VDSL technology for in-house networks.

Finnish national policy

The Finnish national "Broadband Strategy" emphasizes competition to the detriment of infrastructure. The aim is to utilize the existing coper base of the telephone network to its fullest. In this model each user will have an individual subscription with a profit driven telco.

Virtually no encouragement is given to cooperative networks or even in-house networks.

formatting link
The opposition, the "fiber party" is largely concentrated in the Swedish-speaking districts of Ostrobotnia. These people believe in the importance of infrastructure; fiber-optic Ethernet to every house!
formatting link
(in Finnish)

Housing in Finland

Most Finns live in apartment blocks. Finland has the second highest percentage of apartments in Europe after Spain. Also, a large proportion of Finns own their apartments. Most apartment houses are organized as housing cooperatives. The first housing cooperatives were built in Finland around

1900.

Some of the first Finnish Housing cooperatives are located in the Katajanokka neighborhood in Helsinki: -

formatting link
-
formatting link
Finnish writers often translate the Finnish word "asunto-osakeyhtiö" as "housing company". The term "housing cooperative" is more accurate as the form of incorporation of Finnish cooperatives is identical with those in the US. In fact, the housing cooperative model was brought to the United States by Finnish immigrants.

"The first true cooperative development in the United States was started in 1918 by a group of Finnish artisans-the Finnish Home Building Association in Brooklyn, New York. " -

formatting link
-
formatting link

*** *** Vocabulary

Housing cooperative "Housing cooperatives are a form of homeownership where individuals own shares or memberships in a corporation that owns or controls the land and buildings that provide housing. The ownership of a share entitles one to occupy a unit within the cooperative."

formatting link
Council housing (British term) Social housing owned by the city or municipality.

MDU Multi-Dwelling Unit

In-house network A LAN connecting apartments in an apartment block and providing Internet access

Internet connection sharing In English parlance "connection sharing" is often used to refer to sharing your Internet connection between multiple computers. In this text it refers to sharing one WAN connection and possibly one IPv4 address between multiple subscribers.

Operator In the US often referred to as "carrier". A large telco offering telephone and ISP services.

Euro (EUR) The European Currency Unit, now rated at about US $1.32 to one Euro.

Reply to
Petri Krohn

Hi Petri,

Nice project and thank you for shar> [Part 3 Cabling issues - Ethernet on phone wires]

Aluminum burns like crazy, even in alloys. Especially installed vertically in risers, where convection makes a great job of bringing fresh oxygen into the burning area. Besides, it is more expensive than almost any other material used for a conduit. I don't think aluminum alloy made a great choice for riser conduits.

It's a shame such great telephone cable is not available in other parts of the world!

To run one cable per one Ethernet link is not a trick but a norm. Except that the cable should be CAT5 and higher.

At any rate, it looks like you guys threw a dozen of well-established industry standards out the window and attempted to establish your own. Did you give your fire safety authorities a change to take a look at your cabling? I'm especially concerned about those aluminum riser conduits.

Reply to
Dmitri(Cabling-Design.com
[Part 2: Router issues]

Bandwidth-sharing problems

Early HomePNA networks suffered from bandwidth-sharing problems. In an shared Internet connection bandwidth usage between different users may differ by over one thousand fold. The heaviest traffic is caused by file sharing and other p2p-programs.

Without any bandwidth limitations or priorization two or even one BitTorrent user can disable a network and block net access to all neighbors. In an asymmetric ADSL-connection saturation of the uplink will cause the free capacity of the downlink to become unusable. Network latency (ping) grows to over 1 second, practically freezing all other traffic.

ISP:s and housing cooperatives took very different approaches to solving the problem:

In ISP-run networks the built in bandwidth limitation features of HomePNA switches were taken into use. Per user bandwidth was throttled down to a minuscule 128 or 256 kbps.

Cooperative networks wanted to provide each user the full capacity of the network. Artificial restrictions were disliked. The solution was user education. Network activists would monitor network traffic, advise neighbors on proper usage of p2p-software and even temporarily disconnect users who failed to follow the guidance.

Technical solutions

Luckily purely technical solutions have become available to the bandwidth sharing problem in the form of traffic shapers. One useful alternative is the FreeBSD-based firewall distribution m0n0wall with an easily configurable traffic shaper:

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A Finnish company, Staselog also produces a traffic shaper for cooperative in-house networks:
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Functions of a traffic shaper: 1.Delay outgoing traffic so the uplink is newer saturated. 2.Prioritize interactive traffic. 3.Recognize p2p-traffic and set to lowest priority. 4.Give each user an equal share of the usable bandwidth.

Routing with one public IP address

A shared Internet connection will typically use only one public IPv4 address. A router has to perform Network Address Port Translation (NAPT) between the internal network and the Internet. Normally NAPT blocks all users from running servers on their PC:s. This is a problem for p2p applications and may block VoIP services altogether.

A solution is to open a fixed set of port mappings in the router. A set of ports is allocated for each apartment. Also a set of fixed private addresses is allocated for each apartment.

Normal users use DHCP to get their IP addresses in the private network. If a user wants to run a server or a p2p program in active mode, he configures his PC to use his fixed private address. The set of open ports will be mapped to this address.

Example: - address 10.10.10.157 is reserved for apartment 157 - ports 51570 - 51579 are mapped to address 10.10.10.157 in the private network.

A general configuration of the router can be made that can serve any shared residential network. When using m0m0wall this configuration takes the form of an XML file that can easily be distributed. (Hope to make this available after some more editing :-)

Security

Security in an in-house network requires that users cannot communicate directly through the LAN using local IP-addresses or LAN-protocols. All traffic must pass through a router and be based on public IP-addresses. The technique to achieve this is to use "port isolation" in the Ethernet and HomePNA switches. This feature is available in all switches targeted for the MDU-market.

In-house networks usually share one public IP-address among all users. The NAPT router isolates the house network from the Internet and provides a built in firewall.

(Follow-ups to news:alt.comp.networking.connectivity.)

Reply to
Petri Krohn
[Part 3 Cabling issues - Ethernet on phone wires]

"Helsingin Alueverkkoyhdistys" (Helsinki Neighborhood Networking Association) is a group of local volunteers and activists with the altruistic aim of providing "free"¹ Internet access to everyone.

The ultimate goal is to build community owned fiber-optic networks in residential neighborhoods. Equally important is an open network of wireless access points. We believe that universal free and open WLAN access is only possible, if its backed up by an solid infrastructure of shared wired networks.

The first stage is to build in-house networks in the apartment blocks and housing cooperatives. Only when we reach a critical mass of in-house networks can we start connecting them into neighborhood networks. Housing cooperatives are important also in the sense that they can easily be persuaded to give away the free bandwidth needed for the open wireless coverage.

¹ Free in this case means free as in "free lunch"; there is no such thing. Someone will have to pay for the service, or better yet build the infrastructure that provides the service. The idea is to make Internet access a basic infrastructure like streets, electric lighting and running water, available to everyone in need of it. This infrastructure should be provided by the same people who provide these basic services, in most cases the property owners.

Activity has been greatest in two new Helsinki neighborhoods, Ruoholahti and Pikku-Huopalahti. These neighborhoods consist of prefabricated concrete apartment blocks built mainly in the early 1990's with anywhere between 30 and 170 apartments each. -

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Ethernet everywhere!

From the start the aim has been for higher speeds, thus the focus on Ethernet technology.

It was felt that if the slow but popular HomePNA technology would be used for in-house networks, it be a serious hindrance to fiber-optic neighborhood networks. The limited bandwidth that can be delivered by HomePNA can always be served by ADSL or other technologies over coper.

Also the focus has been on finding cheap or "zero-cost" solutions for Ethernet. Housing cooperatives may be willing to invest more heavily, but in Helsinki all new neighborhoods are mixed neighborhoods with both resident-owned co-ops and city-owned social housing. The technical solutions should be so cheap that they can be adopted by council houses with very limited budgets.

Add-on cabling

The standard way of rewiring houses in Finland has been to use diamond drills to pierce floors and walls. Heavy-duty aluminum profile conduits are installed in stairwells to house new cabling. In apartment buildings this effort was only taken up in conjunction with other renovations, like renewing the electrical wiring.

Rewiring for the sake of Internet access had not taken up. The only residential buildings where the effort was made where student dormitories. The costs would be around 400 euros per apartment. We started looking for cheaper, lighter alternatives.

Telephone and central antenna cables to apartments are typically enclosed in

20 mm plastic tubing. This would leave space for an other cable in the same conduit. Also, there should be no need to remove existing telephone wire to provide the additional Ethernet access.

Initially there was a great distrust that new wire could be pulled alongside in the same conduit. The only reference was an undocumented 1995 effort to rewire the dormitories of the Helsinki University of Technology with Cat-5 cable. This was done by student volunteers.

The first houses were rewired in 2003 by volunteer residents. When it was established that the technique can be utilized, this approach was also taken up by a large wiring contractor. Several houses with hundreds of apartments have been wired with a 100% success rate.

Inside the apartment the Finnish legacy telephone socket in one room is replaced with a new faceplate with RJ11 and RJ45 connectors. The cost estimate for this type of "add-on" wiring is about ? 150 per apartment. Success requires that the original construction is up to standard.

Horizontal access

Horizontal telephone cabling in Finnish houses is often done with direct burial cable. There is no horizontal conduit connecting the splices in different stairwells. Even worse, a housing cooperative might consist of several detached buildings separated by an asphalt covered courtyard.

In a prototype house fiber-optic cable was used to connect the Ethernet-switches in the different buildings. Volunteer residents dug up a ditch for the underground conduit connecting the buildings. Later experience has shown this effort to be unnecessary; Finnish telephone cable has proven its ability to carry 100Base-TX Ethernet for over a hundred meters.

The structure for the in-house Ethernet network in a large apartment block:

  1. Place one 24-port Ethernet switch near each stairwell, preferably in the electricity or central antenna closet. Usually the Scotchlok splice for the telephone wiring is located in this same space. 2. Pull new Cat-5e cables from the closet to each apartment. 3. Use free pairs in the direct burial telephone cable to connect the Ethernet switch to the central telephone wiring closet at 100 Mbps. 4. Place the router and central switch at the telephone wiring closet.

Using Cat-3 telephone cable

New Finnish houses built after the year 2000 usually have structural cabling, that is separate Cat-5e cables for Ethernet and telephone with RJ-45 connectors. Older houses houses only have cabling for telephone. Although it is not widely publicized, Finnish telephone cable from the

1990's has a Cat-3 rating.

Houses built after 1995 usually have three twisted pairs serving each apartment. It has turned out to be quite a simple task to convert the cabling to Ethernet use. Originally Finnish legacy telephone sockets are installed with only one pair connected. This leaves two pairs free for use by Ethernet. The transformation consists of exchanging one legacy socket for a RJ-11 / RJ-45 combination faceplate and resplicing the Ethernet-pairs so that only one socket is connected.

The biggest problem for high speed traffic is the Scotchlok splices used to connect different parts of the telephone cabling. These are not made to Cat-3 standards. Practical tests however have shown the connections not to be a problem. Most installations have worked flawlessly even at higher speeds of 100 Mbps.

Distances over 100 meters do not seem to pose a problem either. Zero error operation has been observed in telephone cable at - 100 Mbps for over 100 meters - 10 Mbps for over 150 meters

The trick in running 100Base-TX over Cat-3 telephone cable is to only run one Ethernet link in one cable. This way cross talk between pairs is minimized.

Giving up fixed-line telephone

Houses built before 1994 usually only have two pairs, in the form of a twisted star quad, serving each apartment. Using these pairs for Ethernet traffic poses two problems:

  1. Star quad has an impedance of 120 ohms, which differs from the twisted pair impedance of 100 ohms.
  2. Using both pairs for Ethernet means that the resident would have to give up fixed line telephone service.

In practical tests the impedance mismatch between the pull to the apartment and the multi-paired trunk cable has shown not to be a problem. 10Base-T works reliably.

Giving up the fixed phone may not be a problem. Most voice has already "gone mobile" i.e. moved to mobile phones. The remaining fixed voice traffic is fast moving to VoIP over the Internet. New programs like Skype and VoIP gateway service to consumers has made this move possible.

In a survey of residents in a potential conversion site 83% of residents wanted fixed Internet access. Only 45% required fixed telephone service. This means that over half of the apartments could be converted to Ethernet with about 30% needing ADSL or VDSL service.

Filtered solutions for POTS + Ethernet

It may also be possible to run POTS and Ethernet simultaneously on the same two twisted pairs. Ethernet would occupy the higher frequency band over POTS on the same pair. Splitters or filters would be used in each end to separate the two types of traffic.

A company in the US, Energy Transformation Systems, makes filters for this purpose.

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A Finnish company H.Vesala Ltd. also makes a similar filter, although for ADSL use.
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A slightly different implementation is provided by etherSPLIT.
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(Follow-ups to news:comp.dcom.cabling and news:comp.dcom.lans.ethernet.)

Reply to
Petri Krohn
[Part 4: Wireless networking]

Free wireless access

One of the ultimate goals of this co-operative networking activity is to cover neighborhoods with a "cloud" of free wireless Internet access.

Wireless WLAN networks should not be seen as a primary means of net access, but as an alternative and additional form of access, more like the ultimate icing on the cake.

Giving out free bandwidth requires a fixed backbone with bandwidth to spare. Also the networks need to be based on a culture of sharing.

In the Helsinki wireless "model" open wireless access will be provided by housing cooperatives. Access points are placed in elevator machine rooms with strong sectoral antennas placed on the roofs. In concrete buildings it is difficult to cover the apartments from with in the building but a directional antenna can easily reach neighboring apartments through windows.

Full coverage requires thus cooperation between neighbors. In an reciprocal agreement neighbors can grant each other access to their networks. The practical solution goes even further. A central registry of co-op residents is maintained in a Radius server (radius.helsinkiopen.net). All housing cooperatives share this database for access control. The added value is the ability to freely roam inside and between neighborhoods. Roaming agreements between other networks will further expand the area of movement.

Giving free and uncontrolled access to everybody might seen like an even better idea. This is a much more difficult concept to sell to co-op management boards. The chief concern is not bandwidth usage but security. Network operators want to be able control who uses their network and to keep out spammers and an abusers.

To gain access it is thus not necessary to be a member of an organization giving reciprocal service. It may be sufficient to be a member of an organization who will authenticate you. In the Oulu public access wireless network everyone who is a customer of the public library can gain access to the free network.

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The technical implementation of access control can also be done with the m0n0wall firewall. M0n0wall has a built in captive portal that connects to an external Radius server.

VoIP roaming with DECT handsets

(This an idea for future development.)

It would be highly useful if VoIP based telephony service could be provided to roaming wireless users. The radio access network should be free of any charge for all authenticated users. (The users would of cause pay their VoIP gateway operator for any calls they make to fixed phone lines.

WLAN based VoIP handsets have been expected on the market for several years now. It now seems that WLAN may not be the right technology for mobile VoIP services after all. A far maturer technology is DECT (Digital Enhanced Cordless Telecommunications). These cordless phone products have been on the market for over 10 years with cheapest handset + base station sets available for under 30 euros.

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The DECT Radio or "air" interface provides roaming capabilities similar to the GSM network. DECT roaming is in fact limited by the tie up of DECT handsets to individual base stations.

For true roaming to be enabled the base stations need a complete redesigned.

  1. POTS connectivity replaced by Ethernet/IP-connectivity. 2. Authentication of handset moved to central authentication server or Radius server. 3. DECT roaming mapped to some IP-based roaming scheme, possible mobile IP.

The North American counterpart of DECT, "Personal Wireless Telecommunications" or PWT newer got of the ground. Instead a DSS based system operating at 2.4GHz has gained popularity.

Building combined 2.4GHz WLAN + cordless phone base station might be easier in the US as one antenna might be used to serve both networks. However, the price of 2.4GHz handsets far exceeds the price of DECT handsets. 2.4GHz cordless handsets may not be competitive against true WLAN + VoIP handsets.

(Follow-ups to news:alt.internet.wireless.)

Reply to
Petri Krohn

"Dmitri(Cabling-Design.com)" kirjoitti viestissä news:rE0Xd.574844$ snipped-for-privacy@news.easynews.com...

It seems that in Finland fire safety has never been a big issue as in the US. Most newer buildings are reinforced concrete, older brick and mortar. The few steel constructions are mostly from the 1990's.

Using aluminum risers is not our way of doing things, it is the standard practice used by everyone else.

I don't really think telephone cable is that much different in different parts of the world. All decent cable has twists. The lesson is that you do not really know how good the cable is until you have tried it in practice.

Cat-3 rated cable with a 100 pairs should be able to carry 10Base-T on every pair, that is a total of 1 Gbps! Cat-5 cable with more more than 4 pairs has been missing from the market, it has only recently become available. The way I understand it is that Cat-5 rated cable should be able to carry 100Base-TX on every pair.

(Follow-ups to news:comp.dcom.cabling.)

Reply to
Petri Krohn

It's not so great for destroyers either, as the British found out with HMS Sheffield.

Reply to
James Knott

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