I documented many, many moves and changes to radio locations that needed to be done to give better service- especially around Temple University where the gateway (wired node) capacity was severely lacking. I do know that for whatever reason, Earthlink never was able to get the bucket trucks back in to make those changes. They were busy in the North part of town working on deployment.

I did lots of drive testing with specialized diagnostic gear and I knew where the holes were and what needed to be done.

In about October ’07, most of us were laid off when EL began pulling out of the business, but I had (and still have) high hopes for Philly.

Muni wireless is NOT dead. Here it is Octobet 2010 and I still do it for a living (design/deploy/troubleshoot) and know of many systems that are working well. The ones that work well are by Tropos and a small few others. The ones that do not work well are the ones by Cisco.

The Meraki gear is neat to play with, but is really a toy compared to what real mesh can do. In my experience, the Meraki (and the variants of it) are not suitable for a really controllable network. The dashboard/map is cute, but the fact that Meraki/BATMAN/ROBIN/Open Mesh, etc. present all the clients as looking as if they are behind one gateway does not lend itself to true carrier class control. It makes it difficult if not impossible to control. The system should be able to get IP addresses from an external controller(Mikrotik, Colubris, etc) and let that controller deal with payments, bandwidth control, AAA, etc.

Yes, I played with WiFiCPA and some of the other “accounting systems” that have been designed for the Meraki type gear, but none of it was carrier class. I would not have run my business using it!

Anyway- hello to all my old friends and I will go back into my hole now lol.

Yes, Denise Barton is the marketing director of Tropos.

I’m betting you work for Tropos. I do not see any value in delivering service with an obsolete system when there is funding available to provide robust, reliable, and faster service with multiple radio units. Assuming that Philly really wants to make a impact in delivering service then they should upgrade the network. Yes, I know the other cities that you mention and I know the amount of bandwidth they consume (miniscule). In today’s world application vendors and users require true broadband connectivity. AMR, traffic control, and similar low volume aps can run on anyone’s network but when you factor in things like video streaming and video surveillance you had better provide adequate bandwidth. As for 802.11n, you really don’t gain alot from using true 11n. Packet aggregation performs poorly in most cases when attempting to provide wireless backhaul over multiple hops (adaptive routing protocols just can’t handle it). Spatial multiplexing is virtually impossible and finally, anything you gain on the client side you will ultimately lose on the backhaul side. If we are talking MIMO then all you really can gain from is MRC diversity and beamforming. This is the only real gain from any of the 11n technologies and is provided by almost all vendors now. Philly needs to take the approach of designing the network for capacity, reliability, and speed. If that requires replacement of obsolete “routers” then so be it. I agree with Ken and Phil’s studies that the use of 11n features like MIMO and client beamforming will make a huge difference at the client device but stating that you will get true 11n speeds is ridiculous. 150meg from a mesh node? Come on, really? I am anxiously awaiting the rebirth of Philly and hope that some common sense approaches will prevent the mistakes of the past. Tropos, you’ve got way too much to lose if you let this go south on you. If this goes wrong then we (stakeholders in municipal wifi) will all suffer from the bad press. Just like before. Please get it right Philly! Not just what’s right for Tropos. Good luck Philly! Please keep us posted on your progress.

However, you must have a network that works in order to begin to realize those benefits. The new Philly experiment will be interesting … but it WILL be limited to only a few of the possible applications.

Novarum tested Philly several times during its construction, from the early mid-30 nodes/square mile up to the end at over 50 per square mile. As our analysis then showed – good performance on mesh networks with laptop clients DEMANDED greater than 50 nodes per square mile coverage.

An 802.11g legacy network (such as Philly’s), deployed at 50 nodes per square mile, can provide for competent offloading of city services to high power mobile 802.11g clients with better than 95% coverage – but will likely only offer about 80% coverage to standard low power laptop clients – materially below the 90-95% coverage that modern 3G networks provide. So not just any client will work.

Further – an 802.11g network (even at 52 nodes/square mile) will be expensive to maintain … with node costs 2x the list price of newer 802.11n systems such as Ruckus or Meraki or others.

An 802.11g network … will only be partially useful for offloading smartphone traffic – at this node density, our measurements show that 802.11g smartphones (with lower TX power and poor antennas) get less than 50% coverage. So extended hot spot coverage is possible … but likely only with additional investment to make sure of adequate service.

I hope it delivers value to Philly.

Our recent testing of 802.11n networks strongly shows:

1. A decrease of about 50% in capital costs over the previous 802.11g generation (under $2k list price access points vs $4K).
2. Dramatically improved coverage for low power devices such as laptops and smartphones.
3. Dramatically improved performance – that will equal or exceed future LTE or WiMax performance.
4. Improved indoor coverage. 802.11n laptops as clients to 802.11n access points have better exterior wall penetration than legacy 802.11g CPE.

I would recommend

1. other cities that a modern 802.11n network can probably be deployed today with MUCH better coverage, MUCH better performance at better than half the capital expense of the Philadelphia network when first deployed.

2. Philadelphia build out City Center with 802.11n product that will have superior coverage in the high multipath environment of urban canyons. The Tropos 802.11n product is a very good product – though not as attractively priced as competitors from Ruckus and Meraki.

Could the new N Series products work in this environment of echoes, shadows, and wireless interference? Maybe. But that needs to be proven before the city goes and buys, or if possible upgrades the nodes it may have in stock.

Depending on when this rollout of muni Wi-Fi is supposed to happen in Center City — 2010? 2012? — the answer may or may not be Tropos, depending on what is happening elsewhere in the industry.

True, having Tropos there as the install base argues for staying with them, should they meet the requirements. But as we do not know the timeline and the requirements in a field that is evolving rapidly, it is hard to say now what the Philly network will eventually be.

I am sure that is exactly what Philly’s CTO is trying to figure out now — what the rollout plan is. This is to be a six year project.

As the Chief RF Engineer for EarthLink on the Philly project, I can say that I am very happy to see the city take over the network and keep it alive. Had the city adopted the attitude of being an anchor tenant and and paying EarthLink for the use of the network, EarthLink would have never bailed out of the project and it would have complted the total buildout. The existing Tropos radios can deliver 6 megs to an end user as they are installed now, we tested that in real time, and on that version of firmware it seemed to be the maximum we could achieve. If there is extensive use of fiber to backhaul the traffic, performance should be maintained. I have not worked with any of the upgraded Tropos firmware, but I have no reason to believe that it won’t perform even better.

There were many lessons learned on this project. From a technical perspective the network worked as designed. What didn’t work as planned, was the financial model. Early on, EarthLink failed to hire true wireless engineering talent and therefore went on very poor assumptions of how many transmitters per square mile (around 30) would be required to build a working system. The actual deployed design required around 52 per square mile. That was due to taller buildings in residential neighborhoods than assumed, and dense tree cover. This increased the deployment and operational costs significantly, which of course caused the original financial models to fail. Lesson learned, don’t trust all the marketing hype to be used in for financial forecasts….

An interesting side note, I had conducted some GIS and demographic studies for a round one broadband stimulus applicant. We looked at census block level data for broadband adoption rates below 40%. When I mapped this information, it matched almost exactly where the EarthLink network was deployed and on air. Now either adoption rates were still poor, or the data company was asking the question “Do you SUBSCRIBE to Broadband Services?”. If the later is true I can see why the adoption would be low, people were getting free internet from the system. If the former is true, then the point should be made that “Even if you build it they will not come”. It certainly is a data point that should be looked in to further as far as the consumer aspect of a network like this is concerned.

AT&T should be courted as a potential client. Given the fact that they recently stopped selling IPhones in NYC, I can imagine they are running in to similar capacity problems in other metro markets. If they were to update software in the phone for Philly customers to automatically roam on to the Wi_fi network, that would relieve the stress on the cellular network.

There is certainly a place for Muni networks in the national broadband plan. The original notion that commercial companies would build extensive (and expensive)infrastructure and government would get to use it as a free ride, is finally gone by the wayside. Those of us who have actually built telecom infrastructure knew that idea would not work out. Government officials should have known this too. Now that there is actually some serious cost savings and cost benefit analysis being done, things don’t look so bad on paper even if the government has to contribute some costs to the project. While these wireless networks will never be able to deliver capacity that fiber can, they don’t need to. They can serve specific functions and be an important adjunct to the world of fiber to the curb internet. There will always be a place for the wireless mobility components.