User's Manual

Advanced Configuration Features

Horizon Compact Release 1.01.01 Wireless Ethernet Product User Manual – Volume 1

11.2 Management VLAN Tagging

Note: The configuration of Horizon Compact VLAN tagging is only necessary if you wish to restrict

Horizon Compact management communications to a specific management VLAN.

The Horizon Compact system will pass user VLAN traffic transparently, independent of the Horizon

Compact VLAN settings. The VLAN settings are for Horizon Compact management purposes and do not

affect user data or traffic. VLAN Standard IEEE 802.1Q is supported for Horizon Compact VLAN tagging

and it accommodates up to 4096 VLANs within the “8100” VLAN range. Note that the Horizon Compact

system handles Ethernet frame sizes up to 9600 bytes.

There are three parameters associated with Horizon Compact VLAN tagging:

1. Enable or disable VLAN tagging (set VLAN tagging [on/off])

2. Identify the VLAN tag id to be used with Horizon Compact (set VLAN tag [tag id])

3. Determine whether to allow Horizon Compact to match the VLAN settings in response to

incoming frames, or whether to restrict responses to those incoming frames containing

the programmed VLAN tag. There are two modes (set network protocol strict [off/on])

which are commonly known as “friendly” and “strict” mode.

i. “Friendly” mode. In this mode, Horizon Compact matches the VLAN format of

the incoming frame. If an incoming frame contains a VLAN tag, then Horizon

Compact responds with a VLAN tag matching the incoming frame. If the

incoming frame does not contain a VLAN tag then Horizon Compact does not

insert a VLAN tag in the response. Frames generated by Horizon Compact

(e.g. SNMP traps) will contain the programmed VLAN tag.

ii. “Strict” mode. Horizon Compact will only respond to frames containing the

programmed VLAN tag. All other frames will be ignored. Frames generated by

Horizon Compact (e.g. SNMP traps) will always contain the programmed VLAN

tag.

11.3 802.1P Priority Queuing Implementation in Horizon Compact

QoS implementation is best done on the ingress and egress portions of the transport network. As such,

QoS should be implemented on the Ethernet switches. Once that implementation is in place, the Horizon

Compact can be configured for QoS, should the potential for congestion exist. Enabling CoS/QoS

(802.1P) on Horizon Compact ensures that the high priority traffic is delivered at the expense of lower

priority traffic.

Horizon Compact supports the eight Classes of Service (CoS ) levels (0-7) defined within 802.1P. There

are four CoS Queues within Horizon Compact, numbered 1 to 4. Any of the eight CoS levels can be

assigned to any of the four Horizon Compact CoS Queues. Horizon can also be configured to use the

priority bits found in the DSCP field of IP headers. Any frames not having an IP header can be classified

based on the default class of service value (set cos default value [0 though 7]).

There are three additional Horizon Compact settings that can be used to customize the data flow to

match network requirements:

1. CoS Committed Information Rate (CIR), which determines the guaranteed bandwidth allocated to

a particular Queue.

2. CoS Committed Burst Size, which determines the amount of burst data the Queue can manage.

3. Expedite Queuing (see Section 11.3.3), which allows a Queue to be set as a priority Queue

whereby it delivers its data at the expense of other non-Expedite Queues.