Operating Manual
LK-IP/KNXs REG
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The IP address can be assigned via DHCP or via the ETS configuration. The device operates
according to the KNXnet/IP specification using core, device management, tunneling and routing.
The LK-IP/KNXs REG has an extended filter table for main groups 0 … 31 and can buffer up to
150 telegrams. Power is supplied via the KNX bus.
3.2
Functions
3.2.1
KNX Security
The KNX standard was extended by KNX Security to protect KNX installations from unauthorized
access. KNX Security reliably prevents the monitoring of communication as well as the manipulation
of the system.
The specification for KNX Security distinguishes between KNX IP Security and KNX Data Security.
KNX IP Security protects the communication over IP while on KNX TP the communication remains
unencrypted. Thus KNX IP Security can also be used in existing KNX systems and with non-secure
KNX TP devices.
KNX Data Security describes the encryption at telegram level. This means that the telegrams on the
twisted pair bus are also encrypted.
3.2.2
KNX IP Security for the router function
The coupling of individual KNX TP lines via IP is referred as KNX IP routing. Communication between
all connected KNX IP routers takes place via UDP multicast.
Routing communication is encrypted with KNX IP Security. This means that only IP devices that
know the key can decrypt the communication and send valid telegrams. A time stamp in the routing
telegram ensures that no previously recorded telegrams can be replayed. This prevents the so-
called replay attack.
The key for the routing communication is reassigned by ETS for each installation. If KNX IP Security
is used for routing, all connected KNX IP devices must support security and be configured accord
-
ingly.
3.2.3
KNX IP Security for the interface function
When using a KNX IP router as an interface to the bus, access to the installation is possible without
security for all devices that have access to the IP network. With KNX Security a password is
required. A secure connection is already established for the transfer of the password. All communi
-
cation via IP is encrypted and secured.
