Chapter 3: System planning
Data network planning
Page 3-29
In the Cambium system, NAT supports many protocols, including HTTP, ICMP (Internet Control
Message Protocols), and FTP (File Transfer Protocol). For virtual private network (VPN)
implementation, L2TP over IPSec (Level 2 Tunneling Protocol over IP Security) and PPTP (Point to
Point Tunneling Protocol) are supported.
DHCP
DHCP enables a device to be assigned a new IP address and TCP/IP parameters, including a default
gateway, whenever the device reboots. Thus DHCP reduces configuration time, conserves IP
addresses, and allows modules to be moved to a different network within the Cambium system.
In conjunction with the NAT features, each SM provides:
A DHCP server that assigns IP addresses to computers connected to the SM by Ethernet
protocol.
A DHCP client that receives an IP address for the SM from a network DHCP server.
DMZ
In conjunction with the NAT features, a DMZ (demilitarized zone) allows the assignment of one IP
address behind the SM for a device to logically exist outside the firewall and receive network
traffic. The first three octets of this IP address must be identical to the first three octets of the NAT
private IP address.
Developing an IP addressing scheme
Network elements are accessed through IP Version 4 (IPv4) addressing.
A proper IP addressing method is critical to the operation and security of a network.
Each module requires an IP address on the network. This IP address is for only management
purposes. For security, you must either:
Assign a non-routable IP address.
Assign a routable IP address only if a firewall is present to protect the module.
You assign an 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.
Address Resolution Protocol
As previously stated, the MAC address identifies a module in:
Communications between modules.
The data that modules store about each other.
