GMS Cloud Model

Sept 22, 2014

The Cloud model was introduced to simplify GMS deployment at events. The GMS server will be in the Public Internet "Cloud" and the tablets connect directly to it. This allows GMS "experts" to set up and monitor the GMS server. The event staff can focus on performing their volunteer roles. It also allows the server to be shared by multiple concurrent events.

The main requirement is that the event site WiFi network should allow access to the public Internet.

The Process for using the Cloud

The "Best Practices" steps that should be performed by the event staff (GMS Cloud Engineer) prior to the start of an event are:

Gather the desired number of Android tablets or phones. From the Play store, install the following apps. See this, for more setup details.

GMS (search for GMS FRC)
ZXing Barcode reader

Send the following information to gms@pejaver.com. This allows a server to be configured for the event.

List of users (names, roles, preferred username),
Pit Map for the event
The site's WiFi SSID and password. (Optional, this allows easy tablet setup using QR codes.)
Name and contact info for the "GMS Cloud Engineer" or "Tablet Organization Manager".
Name and contact info for the FTA (optional)

The event staff will receive a Setup QR code via email.

It allows event staff to rapidly configure tablets for each event. On the GMS Login screen, select Setup, point the camera at the QR code and GMS does the rest. QR Codes look like:

Passwords will be selected by the users when they log in.

Role of the Laptop

In the Cloud model, a laptop is not needed to act as the primary server. However, a laptop is highly recommended. Its main purpose is to facilitate recovery in case Internet access is disrupted. While it is standing by, it can add several useful functions, like:

Disaster Recovery (Backup Server)
Pit Administration

Post announcements that can be viewed by teams

Administrative functions

User additions/deletions and password resets from the event site.
Match schedule uploads.
Creating and updating pit map layouts.

Inspection Manager functions

Live display of Inspection status on overhead projector (very cool)
Updating Robot state, weights, assignments, and queue changes.
Viewing GMS inspection reports from previous events.
Inspection Report printouts, to allow falling back to paper.

Preparation is required to make Disaster Recovery swift and smooth. Instructions for setting up the Backup Laptop are here.

Disaster Recovery and Fall Back plan

With the Cloud model, loss of access to the Internet can be disastrous. A laptop can serve as a "Backup" server and will mirror the data on the Cloud server. It will periodically download the latest state from the server in the cloud and keep itself updated. In case of disaster, the recovery procedure is to:

Switch the laptop from "Client" to "Server" mode,
If the event WiFi is lost, power up the preconfigured supplied WiFi AP,
Display a Setup QR code on the laptop and use it to quickly re-configure all tablets. That is it. Done.

This switch should take about 10 minutes. The backup server will be used for the remainder of the event; there are no procedures to revert back to the cloud model. The 'emergency' WiFi coverage may be limited to about 100' from the LRI desk, and Inspectors will have to approach the LRI desk periodically to update their tablets.

Requirements

Internet access is required to the GMS Cloud server:

GMS Cloud Server, http://c.pejaver.com, TCP port 4433
The port number can be changed on request. Ports 80 and 443 are available if firewalls block port 4433 at the event site. Each concurrent event must have a unique port number.

Pros & Cons

The "Local" and "Cloud" models are functionally similar, however the Cloud model has several advantages:

Pros:

The Cloud model eliminates the need for volunteers to set up the GMS laptop. Training for operating the GMS Server Laptop is also eliminated.
It eliminates the need to set up and take down the dedicated WiFi network. Experienced network administrators at the event site can help with any WiFi issues. Training for WiFi setup is also eliminated.
It eliminates the risk of an insufficiently trained volunteer mis-configuring the GMS server.

Cons:

Internet access via WiFi is required at each event location. While this is typically available at all event sites, it may be expensive at some of the large convention centers.
The Cloud model currently does not support Judging. It is ideal for other roles, especially Robot Inspection and Queuing.

The following concerns about the Cloud model have been addressed.

Security:

All data over the Internet can be encrypted using TLS/SSL. Security is actually improved because the private keys will be safe in the service center and will no longer be in the laptops.

Radio interference:

The Cloud mode uses the site's existing WiFi infrastructure. It will not interfere with the FMS 5 GHz WiFi field transmissions.

Connection reliability:

GMS does not need high bandwidth throughput or instantaneous responses. GMS retries communications until it succeeds. The Cloud model may be a bit slower, but will be quite acceptable.

WiFi Availability at venues:

In the last few years, most schools have installed Internet enabled WiFi access for students and staff. This will be quite adequate. Most of the large convention centers already have the WiFi infrastructure, though there may be an extra charge for its use.