Management

ARQ with Selected Repeat and Multirate Feature

The M2400S features ARQ, or “Automatic Repeat Request,” which provides the ability to correct for missing or erred packets of data by asking the sender to re-transmit the data.

Both the AP and SU units implement a form of ARQ known as Selective Repeat.

The units make a first attempt at transmitting a data frame using the 5.5 Mbps rate. Then, if a re-try is required, the 2nd attempt will be at 5.5 Mbps as well. The 3rd and 4th attempts will be at a rate of 2.75 Mbps. After the 4th attempt there will be no more re-tries. A counter describing “maximum retries reached” will be incremented.

A minimum of 100ms is placed between re-transmission requests.

The units buffer up to 1200 frames or 4 seconds worth of RF TX Data frames to support the ARQ algorithm.

The AP unit maintains counters concerning the ARQ algorithm on a per SU basis. The counters shall include the following data:

Total Transmitted Frames Total Retransmission Attempts Total “Maximum Attempts Reached”

The SU also maintains a counter concerning its use of the ARQ algorithm. Counters include the following data: Total Transmitted Frames

Total Retransmission Attempts Total “Maximum Attempts Reached”

Section 8 Management

Section Topics:

Radio Management Access via TCP/IP

SU Management from AP’s command set

SNMP

Radio Management Access Via TCP/IP

The IP Address of an M2400S radio is for management purposes only. The IP address is not used for routing purposes or passing traffic. Users should take care to set appropriate IP schemes for all management activities including upgrading the radio’s firmware. It is not uncommon for users to assign public IP addresses to radios so that they can be accessed from anywhere on the Internet. In order to gain TCP/IP access to the SU (from either side of the wireless network) ensure that the SU switches 2 and 6 are turned on. In order to gain TCP/IP access to the AP from the SU side of the wireless network ensure that AP switch 7 is turned on.

SU Management from AP

The AP provides several commands that permit the management of associated SUs. In fact, most system management functions are performed by issuing commands from the AP. Presented below are a few examples of these commands:

su <all suid, 1..126> su info <suid, 1..126> su linktest <suid, 1..126>

su password <suid all> <rwro> <new password> <new password> su ping <suid, 1..126>

su reboot <suid all>

su sw <suid all> <sw#, 0..7> <on off> su testrflink <suid, 1..126> <r>

su testrflink <all> <r>

Note: SU commands issued from the AP will automatically update the SU’s flash memory. No save ss command is necessary.

Trango Broadband Wireless — User Manual M2400S Rev A

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Trango Broadband M2400S user manual ARQ with Selected Repeat and Multirate Feature, Radio Management Access Via TCP/IP