Case Study #1

Client: Leading estate agent company based in SW London

Project: Restore network connectivity in office and design a build a secure network incorporating all 12 offices

Business Profile

One of London's leading independent estate agents.

Business Problem

The business was compromised by a virus that firstly infected a single office and then spread through their entire network. The virus spread via their VPN office connections. Once an office was infected, they lost Internet and email connectivity because the firewalls could not handle the multiple connection this virus was creating.

The company approached Lemon Computing via a referral and asked to fix their current issue, put a temp solution in place and then design a new network for them .They were looking for a secure network design that would offer;

Our Solution

Our first goal was to restore the Internet and email connectivity in all offices. The virus was identified and a solution built to roll out to each office. Internet connectivity and email was restored in all office. We ensured that critical windows updates were completed to prevent further infection, they were upgraded to the latest Windows service pack, the anti-virus program they were using was removed and replaced with Sophos Anti-virus.

The design of their new network was based on keeping all data, email, web access and administration centrally managed. To achieve that objective we introduced two new Debian servers, installed a lease line (with an ADSL backup) and added a custom built OpenBSD firewall.

The first Debian server was used as the central storage location for all the companies data and user accounts. By doing this we could ensure that every night all the data from the 12 offices was backed up to a single tape. Also users from each office would be required to have a valid username and password before they could log onto the network. No longer would unauthorised users be allowed on the network.

The second Debian server was used as their new email server. Users are no longer downloading email via POP from their ISP and having the emails stored locally on their workstations. We moved their entire email system from POP to IMAP. This also allowed users to move between offices and still have full access to their emails. Webmail access was also supplied to users who may be working outside of their office. Using IMAP also allowed users to see their entire emails from a Webmail client. To reduce spam we installed spamassassin, greylisting and SPF.

The second Debian server was also configured as the web proxy for the entire network. The web proxy was configured to either deny, filter or allow certain trusted websites. Using this proxy we removed trojans, spyware and adware from their network.

A new OpenBSD firewall was installed at the head office. All satellite offices were configured with IPSEC connections to the head office. The IPSEC connection creates an encrypted tunnel to the head office for the safe transfer of data and email over the Internet. Satellite offices were equipped with SonicWalls and we made sure that the necessary precautions were taken so that any virus outbreak would be contained in that particular office.

Key Challenges

Project planning to ensure a smooth migration was carried out with to minimise the amount of down time for the client. The current infrastructure had to be upgrade before the plan could be actioned

Business Benefits