Echelon IP-852 Channel - Manual (Page 33)

IP-852 Channel User’s Guide 25
packet. If the digests match, the packet is authentic. If the digests do not match, the
packet is considered to have been corrupted, tampered with, or otherwise unacceptable,
and is discarded. The digest includes the entire packet, which contains a time stamp for
preventing replay attacks when used in conjunction with a configured channel timeout
value. For more information on the MD5 algorithm refer to RFC 1321.
Note: MD5 authentication should not be confused with authenticated L ON W ORKS
messaging. MD5 authentication applies to IP packets; authenticated L ON W ORKS
messaging applies to native L ON W ORKS packets.
The authentication key, consisting of 16 hex pairs, is set for each IP-852 device using the
device’s configuration interface (for example, using SmartServer configuration Web
pages). Authentication is enabled and the authentication key set for the IP-852 channel
through the IP-852 Configuration Server. To reset a lost authentication key, you must
obtain physical access to the device and reset the key through the device’s configuration
interface.
To enable authentication and set the authentication key on an IP-852 channel, follow
these steps:
1. Click Channel and then click Channel Properties, or right-click on a channel and
click Channel Properties in the shortcut menu. Click the Protocol tab.
Figure 3.3 Protocol Tab
2. Select the Authenticate check box to enable authentication, and then enter 16 hex
pairs that represent the MD5 authentication key into the entry field. The following
is an example key: ABF145E02B5CFF0019BEEFF145E02B5C.