The availability of our service is absolutely critical to our customers and to our own business.

Since 2004, when we made significant infrastructure improvements, we have achieved the gold standard of 99.999% availability.

Service continuity is exceptionally important to us. That's why we've taken considerable steps to ensure that Postcode Anywhere is always available:

• 2 completely autonomous data centres
• Load balanced servers in each data centre
• Data centres employ fully diverse routing and multiple carriers
• Automatic failover between servers and between data centres
• No single point of failure

All this means that even a catastrophic failure of a data centre can be tolerated and will not impact on the availability of Postcode Anywhere. Traffic will simply reroute to the other data centre within 60 seconds.

Both the Postcode Anywhere web site and the web service are load balanced as detailed above. Generally subsequent connections to the service are made to the same data centre and the same server but this can change under certain conditions.

For this reason, you should be aware of the different IP addresses and ports used by the website and web service if you restrict access to Postcode Anywhere using firewall rules:

Primary data centre (70% traffic load under normal conditions)
217.10.139.201 port 80 (HTTP)
217.10.139.201 port 443 (HTTPS - only used for online purchases)

Secondary data centre (30% traffic load under normal conditions)
194.75.186.201 port 80 (HTTP)
194.75.186.201 port 443 (HTTPS - only used for online purchases)

Primary data centre (70% traffic load under normal conditions)
217.10.139.200 port 80 (HTTP)
217.10.139.200 port 443 (HTTPS - only used for online purchases)

Secondary data centre (30% traffic load under normal conditions)
194.75.186.200 port 80 (HTTP)
194.75.186.200 port 443 (HTTPS - only used for online purchases)

Note: all web service facilities are available over HTTPS as well as HTTP. However, we recommend against the use of HTTPS because of the significant additional overhead required to establish an HTTPS session.