User's Manual Part 2
Release8PlanningGuide
Issue2,November2007 Draft5forRegulatoryReview 162
13.4 DEVELOPINGANIPADDRESSINGSCHEME
Cyclone network elements are accessed through IP Version 4 (IPv4) addressing.
A proper IP addressing method is critical to the operation and security of a Cyclone
network.
Each Cyclone module requires an IP address on the network. This IP address is for only
management purposes. For security, you should either
• assign an unroutable IP address.
• assign a routable IP address only if a firewall is present to protect the module.
You will assign IP addresses to computers and network components by either static or
dynamic IP addressing. You will also assign the appropriate subnet mask and network
gateway to each module.
13.4.1 AddressResolutionProtocol
As previously stated, the MAC address identifies a Cyclone module in
• communications between modules.
• the data that modules store about each other.
• the data that BAM or Prizm applies to manage authentication and bandwidth.
The IP address is essential for data delivery through a router interface. Address
Resolution Protocol (ARP) correlates MAC addresses to IP addresses.
For communications to outside the network segment, ARP reads the network gateway
address of the router and translates it into the MAC address of the router. Then the
communication is sent to MAC address (physical network interface card) of the router.
For each router between the sending module and the destination, this sequence applies.
The ARP correlation is stored until the ARP cache times out.
13.4.2 AllocatingSubnets
The subnet mask is a 32-bit binary number that filters the IP address. Where a subnet
mask contains a bit set to 1, the corresponding bit in the IP address is part of the network
address.
Example IP Address and Subnet Mask
In Figure 45, the first 16 bits of the 32-bit IP address identify the network:
Octet 1 Octet 2 Octet 3 Octet 4
IP address 169.254.1.1 10101001 11111110 00000001 00000001
Subnet mask 255.255.0.0 11111111 11111111 00000000 00000000
Figure 45: Example of IP address in Class B subnet
In this example, the network address is 169.254, and 2
16
(65,536) hosts are addressable.