Cambium Networks PMP 450, Руководство по планированию

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PMP 450 Planning Guide
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.
When NAT is enabled, a reduction in throughput is introduced at the SM (due to processing overhead).
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
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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 should either
•
assign a non-routable 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.
Address Resolution Protocol
As previously stated, the MAC address identifies a module in
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communication between modules.
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the data that modules store about each other.
The IP address is essential for data delivery through a router interface. Address Resolution Protocol (ARP)
correlates MAC addresses to IP addresses.
pmp-0047 (March 2014)
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