Categories: S60 | Platform Security | Networking | TCP/IP

This page was last modified 10:55, 2 December 2007.

From Forum Nokia Wiki

This article is intended for network application developers, who wish to 'hard-code' IP addresses for certain server names. This mechanism comes in handy when the developer wants to redirect network traffic from a live site to another test site, without the knowledge of the end user.

Concept

The "HOSTS" file is a lookup table. When the network application (such as web browser) requests to create a connection with a network server, the IP address is needed to create the connection. If the requesting application asks for "www.forum.nokia.com", this name must be converted to an IP address. The domain name system consults the HOSTS file to see if there is an entry for "www.forum.nokia.com" in it. If there is, then the IP address given in that entry will be used to create connection to.

This substitution will continue so long as the HOSTS file is present. To revert back to original behavior, one should simply delete this file.

Example HOSTS file:

# This is a sample HOSTS file (taken from a MS-Windows system)
102.54.94.97 rhino.acme.com # source server
38.25.63.10 x.acme.com # x client host

Like all the other advanced operating systems, Symbian includes support for HOSTS file. In all the operating systems, there is always a special place for HOSTS file. E.g. in UNIX like systems, the file goes in /etc . We will now see where to save the HOSTS file on S60 devices.

Pre-PlatSec World

C:\system\data\hosts

PlatSec World (S60 3.x onwards)

C:\private\10000882\hosts

Since this is a "private" location, one requires a file browser (or an application) with AllFiles capability to copy the file to this location.

Recommended Reading

• More general information on HOSTS file

• Domain Name System