Chapter 6 WAN Setup

Table 20 Network > WAN > Internet Access Setup: Advanced Setup (continued)

LABEL

DESCRIPTION

Multicast

Multicast packets are sent to a group of computers on the LAN and are

 

an alternative to unicast packets (packets sent to one computer) and

 

broadcast packets (packets sent to every computer).

 

Internet Group Multicast Protocol (IGMP) is a network-layer protocol

 

used to establish membership in a multicast group. The ZyXEL Device

 

supports IGMP-v1, IGMP-v2and IGMP-v3. Select None to disable

 

it.

 

 

ATM QoS

 

 

 

ATM QoS Type

Select CBR (Continuous Bit Rate) to specify fixed (always-on)

 

bandwidth for voice or data traffic. Select UBR (Unspecified Bit Rate)

 

for applications that are non-time sensitive, such as e-mail. Select

 

VBR-RT(real-time Variable Bit Rate) type for applications with bursty

 

connections that require closely controlled delay and delay variation.

 

Select VBR-nRT(non real-time Variable Bit Rate) type for

 

connections that do not require closely controlled delay and delay

 

variation.

 

 

Peak Cell Rate

Divide the DSL line rate (bps) by 424 (the size of an ATM cell) to find

 

the Peak Cell Rate (PCR). This is the maximum rate at which the

 

sender can send cells. Type the PCR here.

 

 

Sustain Cell

The Sustain Cell Rate (SCR) sets the average cell rate (long-term)

Rate

that can be transmitted. Type the SCR, which must be less than the

 

PCR. Note that system default is 0 cells/sec.

 

 

Maximum

Maximum Burst Size (MBS) refers to the maximum number of cells

Burst Size

that can be sent at the peak rate. Type the MBS, which is less than

 

65535.

 

 

PPPoE

This field is available when you select PPPoE encapsulation.

Passthrough

In addition to the ZyXEL Device's built-in PPPoE client, you can enable

(PPPoE

PPPoE pass through to allow up to ten hosts on the LAN to use PPPoE

encapsulation

client software on their computers to connect to the ISP via the ZyXEL

only)

Device. Each host can have a separate account and a public WAN IP

 

 

address.

 

PPPoE pass through is an alternative to NAT for application where NAT

 

is not appropriate.

 

Disable PPPoE pass through if you do not need to allow hosts on the

 

LAN to use PPPoE client software on their computers to connect to the

 

ISP.

 

 

MTU

 

 

 

MTU

The Maximum Transmission Unit (MTU) defines the size of the largest

 

packet allowed on an interface or connection. Enter the MTU in this

 

field.

 

For ENET ENCAP, the MTU value is 1500.

 

For PPPoE, the MTU value is 1492.

 

For PPPoA and RFC 1483, the MTU is 65535.

 

 

Packet Filter

 

 

 

Incoming Filter

 

Sets

 

 

 

 

105

P-660HW-Tx v3 Series User’s Guide