Cisco Model D-PCG1000 PowerKEY CAS Gateway Installation Guide
Chapter 1 Introducing the Netcrypt Bulk Encryptor
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Unicast content that passes
through a Netcrypt Bulk Encryptor
has the IP address of that
Netcrypt Bulk Encryptor in the
destination IP address field of the
IP header.
Unicast content output from a Netcrypt
Bulk Encryptor has the IP address of that
Netcrypt Bulk Encryptor in the source IP
address field of the IP header, and the IP
address of the QAM modulator in the
destination IP address field of the IP
header.
Layer 2/3 Networks and Address Resolution Protocol
The Netcrypt Bulk Encryptor follows standard network rules and uses Address
The Netcrypt Bulk Encryptor follows standard network rules and uses Address
Resolution Protocol (ARP) to resolve required MAC addresses:
In bi-directional Layer 2 networks, QAM modulators must respond to ARP
requests.
In Layer 3 networks, the assigned gateway must respond to ARP requests.
QAM modulators on the other side of one-way transport networks must be assigned
IP addresses on different networks than the Netcrypt Bulk Encryptor. Per network
rules, this will cause the Netcrypt Bulk Encryptor to issue an ARP request using its
gateway IP address — not the IP address of a QAM modulator. In this case, the
gateway, which may be the transport network, must support ARP.
It is recommended to connect the Netcrypt GbE ports to a Layer 3 router, as opposed
It is recommended to connect the Netcrypt GbE ports to a Layer 3 router, as opposed
to a Layer 2 switch. It is best to assign IP addresses out of separate subnets. The use
of a /30 subnet mask minimizes wasted IP addresses. If the GbE interfaces are
placed in the same Layer 3 VLAN, then the routing switch requires static MAC
addresses
If Netcrypt GbE ports are connected to a Layer 2 switch, then static MAC addresses
If Netcrypt GbE ports are connected to a Layer 2 switch, then static MAC addresses
must be used in the switch due to the “one-way” nature of most MPEG traffic.
Unicast and Multicast Behavior
IP unicast and IP multicast addresses are supported at either or both of the Netcrypt
IP unicast and IP multicast addresses are supported at either or both of the Netcrypt
Bulk Encryptor input and output for sessions and Transport Stream Routes (TSRs).
Streams may be received by the Netcrypt Bulk Encryptor as unicast and output as
multicast or vice versa.
The current release of the Netcrypt Bulk Encryptor does support Internet Group
The current release of the Netcrypt Bulk Encryptor does support Internet Group
Management Protocol, Version 2 (IGMPv2).