User's Manual

User
AN-100U/UX Base Station
Manual
70-00058-01-04 Proprietary Redline Communications © 2010 Page 103 of 136 April 19, 2010
The Max. Sustained Rate determines the connection queue size, and controls the rate
packets are forwarded over the wireless interface, but does not restrict the rate at which
packets are received from the local Ethernet interface. Ethernet flow control mechanisms
are not effective because the Ethernet switch has no information about how packets are
assigned to individual connections.
The following table lists the queue sizes for a range of Max. Sustained Rates.
Table 51: Queue Sizes for 10 ms Frame Duration
Max Sustained Rate (bps)
Queue Size (Bytes)
2 508 800
30 640
1 214 400
24 072
1 024 000
23 120
409 600
20 048
204 800
19 024
102 400
18 512
51 200
18 256
There is no data aging, and the queue stores packets until they are transmitted over the
wireless interface or the connection is deleted. If a connection queue reaches capacity,
then newly arriving packets are immediately discarded.
Under normal conditions, many services and applications are competing for the same
bandwidth, and the traffic may arrive in bursts. The service class type and service flow
settings must be selected to facilitate forwarding data onto the wireless link at a rate that
does not overflow the queue for that connection.
6.2.5 Uplink Subchannelization
The uplink subchannelization (USC) feature (AN-100UX only) provides opportunities to
increase sector uplink throughput and establish wireless links to medium and low signal
subscribers (v2.1 or higher). Refer to section 7.1: Self-Provisioning Features on page
111 for additional details.
6.2.6 Backhaul Mode
The RedMAX equipment can be configured to operate as a simple wireless bridge
without QoS services. This is accomplished using a one uplink and one downlink
connection both set to Best Effort (BE) and a Max. Sustained Rate of 25.4 Mbps. The
uplink/downlink ratio is set to 'dynamic' and is adjusted automatically based on traffic
patterns.
The Secondary Management Channel (SMC) exchanges management and configuration
data over the wireless interface with subscribers that have remote management
enabled. This includes all HTTP, TELNET, FTP, and SNMP exchanges. Bandwidth is
assigned only when required by pending management operations. All unused bandwidth
is available for other scheduling activities.
The SMC bandwidth is allocated (as required) in two passes:
Pass 1: Downlink: 256 Kbps (max.) shared between all subscribers.
Uplink: 32 Kbps (max.) per subscriber.
Pass 2: All unassigned uplink and downlink bandwidth may be assigned to SMC
connections.
For example, when a software upgrade is in process for a subscriber, the downlink
connection is guaranteed a minimum of 256 Kbps (320 bytes/wireless frame @ 10 ms
Frame Duration). Note that a portion of this bandwidth may also be allocated to other