Traffic Shaping - Pirelli P.RG F4202N User Manual

TRAFFIC SHAPING

© (2010) Pirelli Broadband Solutions S.p.A. All Rights Reserved. Proprietary Use Pursuant to Cover Page Instructions.
QoS Section
P.RG F4202N
This screen is divided into two main sections, 'Matching' and 'Operation', which
are for defining the operation to be executed when matching conditions apply.
- Matching: Use this section to define the rule's conditions, which are the LAN
computer's parameters to be matched.
- Operation: Set rule priority with Quality of Service.
Click 'OK' to save the settings.
3.
Traffic Shaping is the solution for managing and avoiding congestion where a
high speed LAN meets limited broadband bandwidth. A user may have, for ex-
ample, a 100 Mbps Ethernet LAN with a 100 Mbps WAN interface router. The
router may communicate with the ISP using a modem with a bandwidth of
2Mbps. This typical configuration makes the modem, having no QoS module,
the bottleneck. The router sends traffic as fast as it is received, while its well-
designed QoS algorithms are left unused. Traffic shaping limits the bandwidth of
the router, artificially forcing the router to be the bottleneck.
A traffic shaper is essentially a regulated queue that accepts uneven and/or
bursty flows of packets and transmits them in a steady, predictable stream so
that the network is not overwhelmed with traffic.
While Traffic Priority allows basic prioritization of packets, Traffic Shaping pro-
vides more sophisticated definitions. Such are:
 Bandwidth limit for each device
 Bandwidth limit for classes of rules
 Prioritization policy
 TCP serialization on a device
Additionally, you can define QoS traffic shaping rules for a default device.
These rules will be used on a device that has no definitions of its own. This en-
ables the definition of QoS rules on Default WAN, for example, and their main-
tenance even if the PPP or bridge device over the WAN is removed.
HBK 939800036-A1 75