Re: MP2 Rachel

[T Gillett]

Hi Joe

The VT-RACHEL device is intended to be used in a single classroom where it will support around 30 students connected by wifi. It will provide the students with access to the local RACHEL library contents over the local wifi link, so the response time is quite fast.

As well as the limit on wifi connections there is also a limit on how fast the internal web server can service page requests. If you increase the number of students accessing the device then the web server will not keep up with the workload and performance will suffer.

You can network the devices on the WAN side in order to share a school backbone network for access to upstream resources such as an Internet connection. With this arrangement, each classroom has the RACHEL library content served locally, but can also access Internet resources through the same wifi connection.

By default the VT-RACHEL firmware is configured for Ethernet WAN so that you can plug it into a LAN. But you can also configure it for mesh on the WAN side for a wireless backbone if you wish.

If you wish to provide a single copy of the library content to serve the whole school, then you should consider providing a more powerful device to run the web server, and then network that via APs etc. A PC running Ubuntu is commonly used for the web server in this arrangement. The RACHEL library content is very simple to use with any web server - it is just a collection of static pages. You can get one VT-RACHEL device and simply copy the content from the USB onto a hard disc in the central web server.

Our deployments in Cambodia and Malaysia were done on the basis of providing one VT-RACHEL device in a classroom. These were small rural schools so typically had only one or two classrooms equipped for computer use - mostly OLPC XO laptops.

In some of the schools, the VT-RACHEL unit was connected by Ethernet cable to a TP Link MR3020 acting as a host for a 3G USB modem for Internet access.

Something to keep in mind with remote deployments is the aspect of reliability of the system. There is often little or no technical support available if things go wrong.

By providing one device per classroom you have a situation where each device can operate independently, so there is no single point of failure.

Also, the wifi connection is very robust when the AP device is located in the classroom, so you don't get the situation where some client devices struggle to get a reliable connection. I have found that using multiple small APs gives a better solution for covering a campus than trying to saturate the area with a few high power APs.

Regards
Terry

On 02/03/2016 12:27 PM, "Joe Bunefa" <joe.b...@gmail.com> wrote:

Hi Terry.

Thanks for the infor. Iam trying to deploy in a secondary school.

Plan to cover the entire campus. If i put a mp2 RACHEL in the center  building and mesh up with other ap to extend range??.

How was yr setup in Cambodia and Malaysia?

Hear from you soon.

Cheers.
Joe

[T Gillett]

Just for info, the next version of the VT-RACHEL firmware for the MP02 will provide two AP interfaces.

One will have access only to the local RACHEL library resources, and the other will have access to both local and upstream resources.

This will allow the device to be used for public access to the local resources, and controlled access to the upstream resources.

Either or both interfaces can be selected to operate.

[T Gillett]

Joe

If you put an MP02 in each classroom, then you will have a good stable wifi setup regardless of how you serve the RACHEL content.

You can also put them on different, non-overlapping channels - 1, 6, 11 - to reduce wifi congestion.

(Be careful about what other APs are operating on the site.)

This would be a good way to get started and try out the concept.

I guess the computer lab rooms will allow connections from the MP02s back to an Internet gateway via Ethernet cable, but you might have to do something wireless for the third classroom 100 metres away.

The new firmware is not yet available, but it will be a simple firmware upgrade to install it on existing devices.

Regards

Terry

On Wed, Mar 2, 2016 at 1:57 PM, Joe Bunefa <joe.b...@gmail.com> wrote:

Hi Terry.

Thanks and appreciate your great infor.

They have two computer  lab and a new one about hundred meters away.

What i will do is put one device per classroom. Do you want me to buy 3 and put each mp2 rachel in each classroom. I know staff would like to use and wants us to extend wifi coverage to domitories and staff residence.

I might also consider a ubuntu pc for local webserver.

Thanks and looking forward to hear.

Cheers.

[Joe Bunefa]

What is the power or watts for a mp2 rachel. Planning for remote schools with out main power grid. Will use solar.

Thanks

[Song, Stephen]

Hi Joe,

I estimate the power consumption for the MP2 Rachel is about 1W.

Regards... Steve

On 8 March 2016 at 15:08, Joe Bunefa <schu...@gmail.com> wrote:

What is the power or watts for a mp2 rachel. Planning for remote schools with out main power grid. Will use solar.

Thanks

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[Joe Bunefa]

Thanks Steve and this is great to power on solar.

Please fast track my order. Will place few more soon.

Cheers.
Joe

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[T Gillett]

The nominal power requirement for the MP02-RACHEL is 2 Watts at 12 Volts.

The peak current drain from the 12 Volt supply is 150mA, typical is 120mA.

On Wed, Mar 9, 2016 at 5:08 AM, Joe Bunefa <schu...@gmail.com> wrote:

What is the power or watts for a mp2 rachel. Planning for remote schools with out main power grid. Will use solar.

Thanks

[edwin]

Hi, Joe,

It is 9 ~ 15v.
Power consumption between 0.5~1w

Best Regards,
Edwin

> -----邮件原件-----
> 发件人: village-...@googlegroups.com
> [mailto:village-...@googlegroups.com] 代表 Joe Bunefa
> 发送时间: 2016年3月9日 3:08
> 收件人: Village Telco Development Community
> 主题: [vt-dev] Re: MP2 Rachel

>
> What is the power or watts for a mp2 rachel. Planning for remote schools with
> out main power grid. Will use solar.
>
> Thanks
>

[T Gillett]

With the RACHEL version, there is some additional power required for the 32GB memory, and there are some short term peak power requirements which means that you should allow for 2W of power and 150mA peak.

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[Pascal Laurent]

Joe,

Please share the experience with us once you are done with he setup and implementation. I am interesting to learn how you implement the solar system to power the MPs. What type of equipments you use and so forth. If you could document the process that would have wonderful educational values for us.

Thank so much in advanced,
Pascal

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[Joe Bunefa]

Hi Pascal.

Thanks and sure will document this when we start rolling out to remote schools in the provinces.

The first one will be for a town secondary school which we have setup ncomputing terminals for them since 2009. Elibrary will be our first project and we expecting more for remote schools.

Also we planning to try out chrome laptops

Thanks.
Joe

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