User guide

Canopy System User Guide Configuring an AP for the Destination
pmp-0229 (Mar 2013)
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Prioritize TCP ACK
To reduce the likelihood of TCP acknowledgement packets being dropped, set this parameter to
Enabled. This can improve throughput that the end user perceives during transient periods of
congestion on the link that is carrying acknowledgements. This parameter, when enabled, can be
particularly useful when running bi-direction FTP sessions over the link. If a link is primarily used
for video surveillance, it is recommended to configure this parameter to “Disabled”. See AP-SM
Links on Page 99.
Multicast Destination Address
Using Link Layer Discovery Protocol (LLDP), a module exchanges multicast addresses with the
device to which it is wired on the Ethernet interface. Although some switches (CMMmicro, for
example) do not pass LLDP addresses upward in the network, a radio can pass it as the value of
the Multicast Destination Address parameter value in the connected device that has it populated.
In this way, an SM can report to Prizm, for example, the multicast address of a connected remote
AP, and thus allow Prizm to discover that AP. To allow this, set the message mode in the remote
AP to LLDP Multicast. The SM will pass this address in broadcast mode, and the CMMmicro
will pass the address upward in the network, since it does not discard addresses that it receives in
broadcast mode.
Where the AP is not behind another device, the Broadcast mode will allow discovery of the AP.
DHCP Relay Agent
The AP may act as a DHCP relay for SMs and CPEs underneath it. The AP will make use of the
DHCP Option 82 (DHCP Relay Agent Information) from RFC 3046 when performing relay
funtions. The AP offers two types of DHCP relay functionality:
• Full Relay Information. Configuring the DHCP Full Relay Operation will take broadcast
DHCP packets and send them to a Unicast server in unicast mode. This way the DHCP
requests and replies can be routed like any other UDP packet.
• Only Insert Option 82. This option leaves the DHCP request on its broadcast domain as
opposed to DHCP Full Relay Operation which will turn it into a unicast packet.
In order to accommodate setting up pools or classes for different VLANs, the Option 82 field will
include information to tell the server what VLAN the client is on.
DHCP Server (Name or IP Address)
This field represents the DHCP server for which DHCP messaging relayed for SMs and CPEs
situated beneath the AP. The DHCP relay server may be either a DNS name or a static IP address
in dotted decimal notation. Additionally the management DNS domain name may be toggled such
that the name of the DHCP relay server only needs to be specified and the DNS domain name is
automatically appended to that name. The default DHCP relay server addresses is
255.255.255.255 with the appending of the DNS domain name disabled.