User:Holt/XS Community Edition/0.2/Project Specifications

School Server - Community Edition 0.2 Project Specifications

Summary

The school server is very similar in concept to a standard home wireless router. In everyday usage it provides various services which extend capabilities of the connected laptops while being totally transparent to the user. These services can include:

• Network connection – various services similar to what you would find in a home router.
• Presence server – Augments sugar's native collaboration functionality.
• Web filtering – Enables schools to comply with local legal restrictions on internet access for children.
• FUTURE - Security – XO related security services.
• FUTURE - Content management

Reference User

The XS-CE has two different types of reference user:

• Skilled sysadmins running micro-deployments
• OLPC-AU schools.

As a result this design might not apply in all situations in all deployments. These limitations ease design and development while creating a functional reference implementation.

Hardware

School servers can be either XO-1.75 or standard x86 based hardware.

XO-1.75

In common usage, the XO may be augmented by SD cards and two off the shelf USB devices:

• External hard drive – Allows the server to provide additional storage capabilities.
• Network connector – Allow the server to offer internet access to connected XO's.

This strategy it is simple for a deployment to inventory and maintain school servers.

X86

For greater flexibility some schools will want to use standard x86 hardware.

Deliverable

A RPM combined with tested installation instructions necessary to convert a standard XO-1.75 into a School Server.

FUTURE - An image combined with tested installation instruction which can be flashed onto a laptop by deployment support staff. At initial 'power on' the support staff or teacher will be greeted by a simple GUI to do initial configuration.

OS

The school server will be based on OLPC-OS 12.1 on f17

NOTE: Limiting the deliverable to single OS variant meets the base requirements while limiting complexity.

User Interface

Command Line – Command line configuration should be discouraged at all levels. Target users are often not familiar with the linux system administration. Initial setup or fixing a problem with their server is not a good time to introduce system administration skill.

FUTURE - Browser based GUI. – The primary configuration tool will be a browser based GUI. This technology is well understood by developers. Many end uses have familiarity with Browser based setup.

A browser based allow admin from three physical distances:

• On screen. Initial setup and admin of security sensitive services can be limited to on screen.
• On site. Subsequent management of non security sensitive services can be done by a teacher or local admin logging in to the machine.
• Remote. Deployment level support staff can log in and remotely maintain and monitor services.

FUTURE - Remote administration – There are several systema such as CFEngine and puppet which enables remote management. While not immediately required by AU it is highly desirable by large deployment.

Modular design

One of the key design criteria of all successful community based projects is modularity. The original XS suffered because developers took used monolithic design overcome hardware limitations on the XO-1. The improvements in the XO-1.75 allow for the potential inefficiencies of modularity.

Core Server

The core server will contain 5 services which can be extended via extended services.

Service: Network setup
Purpose:
Provider: xs-setup-network

Service: Dynamic Host Configuration Protocol
Purpose: Schoolserver and clients need to be on same subnet.
Provider: dhcpd

Service: Iptables -- Network Address Translation (NAT)
Purpose: Permits all XO’s to access the internet.
Provider: gateway

Service: Internet domain name server
Prupose:
Provider: named

Service: Backup of student work and restore
Purpose:
Provider: idmgr

Service:Jabber server
Purpose: collaboration > 15 clients needs to work.
Provider: ejabberd

Extended Services

Service: Web server
Purpose: Building block for many other extended services
Provider: apache

Service: proxy server and web cache
Purpose: bandwidth, web-filtering, web-monitoring
Provider: squid

Service: OLPC-update
Purpose: OLPC-update is necessary to update the kernel of XO
Provider: rsync

Service: Activity update
Purpose: Enables teachers to easily distribute new or updated activities to their students
Provider: activity updater

Service: Virtual Private Network (VPN)
Purpose: Creating secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities
Provider: open vpn

Future Services

Service: Content filtering (TimM??)
Purpose: age-appropriate surfing, legal compliance, religious risks
Provider: dansguardian

Service: (GeorgeH, Gerald)
Purpose: local distribution/replication of Sugar Activities etc
Provider: pdsh

Service: (JerryV, GeorgeH)
Purpose: Journal submissions to teacher, academic record (homework etc)
Provider: WebDAV

Service: (DSD, GeorgeH)
Purpose: remote upgrading/admin of XS servers (semi-automated)
Provider: Puppet

Service: Book server (SameerV, AlexK, GeorgeH struggling!)
Purpose: compete with Khan Academy?
Provider: pathagar