Traffic Shaping - ZyXEL Communications P-793H v3 User Manual

Chapter 6 WAN Setup
Figure 35 Traffic Redirect Example
The following network topology allows you to avoid triangle route security issues when the backup
gateway is connected to the LAN. Use IP alias to configure the LAN into two or three logical
networks with the P-79X itself as the gateway for each LAN network. Put the protected LAN in one
subnet (Subnet 1 in the following figure) and the backup gateway in another subnet (Subnet 2).
Configure filters that allow packets from the protected LAN (Subnet 1) to the backup gateway
(Subnet 2).
Figure 36 Traffic Redirect LAN Setup

6.8 Traffic Shaping

Traffic Shaping is an agreement between the carrier and the subscriber to regulate the average rate
and fluctuations of data transmission over an ATM network. This agreement helps eliminate
congestion, which is important for transmission of real time data such as audio and video
connections.
Peak Cell Rate (PCR) is the maximum rate at which the sender can send cells. This parameter may
be lower (but not higher) than the maximum line speed. 1 ATM cell is 53 bytes (424 bits), so a
maximum speed of 832Kbps gives a maximum PCR of 1962 cells/sec. This rate is not guaranteed
because it is dependent on the line speed.
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