Step 6 – Nortel Networks Nortel Business Services Gateway BSGX4e User Manual

Page 24

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Configuration process

3 Wizard pages

Step 6

Quality of Service Setup page


QoS is a system that reserves some amount of
bandwidth for critical functions at times when
your Internet connection is at maximum

Placing a function under QoS management
means it has protected and uninterrupted
service. Functions not under QoS
management may experience delays and
interruptions during times of data traffic

Critical functions are assigned to “QoS
Groups,” which then get priority over
unprotected traffic that the BSGX4e is
transmitting out its WAN port.

The upstream bandwidth reserved for the QoS groups is relative to the total amount of bandwidth
available on your upstream Internet connection (

Max Bandwidth

field). The total bandwidth

allocated to all groups combined cannot be more than 90 percent of

Max Bandwidth


The wizard configures the two most critical QoS groups for you:


The Voice group is for VoIP phone functions.


The Control group is for network functions that are critical to the BSGX4e’s operation.
PPP and ARP are two such functions that get placed into this group.

QoS can protect traffic in both the upstream and downstream directions. Downstream QoS works
differently from the upstream. When downsteam QoS is enabled in one or more QoS groups, the
BSGX4e limits incoming traffic that is not destined for a function protected by one of those QoS
groups. This creates sufficient incoming bandwidth for the protected traffic.


Click the

Set Default

button to get started. This loads the following values into the page.

Table 3

Default Values



Upstream QoS


Downstream QoS


Voice Group


Control Group