ZyXEL Communications VMG892-B10A User Manual page 58

Chapter 5 Broadband
Table 9 Network Setting > Broadband > Add New WAN Interface/Edit (ADSL over ATM - Bridge
Mode) (continued)
LABEL
Mode
ATM PVC Configuration (These fields appear when the Type is set to ADSL over ATM.)
VPI
VCI
DSL Link Type
Encapsulation
Mode
Service
Category
Peak Cell Rate
Sustainable Cell
Rate
Maximum Burst
Size
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DESCRIPTION
Select Bridge when your ISP provides you more than one IP address and you want the
connected computers to get individual IP address from ISP's DHCP server directly. If you
select Bridge, you cannot use routing functions, such as QoS, Firewall, DHCP server and
NAT on traffic from the selected LAN port(s).
The valid range for the VPI is 0 to 255. Enter the VPI assigned to you.
The valid range for the VCI is 32 to 65535 (0 to 31 is reserved for local management of ATM
traffic). Enter the VCI assigned to you.
This field is not editable. The selection depends on the setting in the Encapsulation field.
EoA (Ethernet over ATM) uses an Ethernet header in the packet, so that you can have
multiple services/connections over one PVC. You can set each connection to have its own
MAC address or all connections share one MAC address but use different VLAN IDs for
different services. EoA supports ENET ENCAP (IPoE), PPPoE and RFC1483/2684 bridging
encapsulation methods.
PPPoA (PPP over ATM) allows just one PPPoA connection over a PVC.
IPoA (IP over ATM) allows just one RFC 1483 routing connection over a PVC.
Select the method of multiplexing used by your ISP from the drop-down list box. Choices
are:
• LLC/SNAP-BRIDGING: In LCC encapsulation, bridged PDUs are encapsulated by
identifying the type of the bridged media in the SNAP header. This is available only when
you select IPoE or PPPoE in the Select DSL Link Type field.
• VC/MUX: In VC multiplexing, each protocol is carried on a single ATM virtual circuit
(VC). To transport multiple protocols, the Device needs separate VCs. There is a binding
between a VC and the type of the network protocol carried on the VC. This reduces
payload overhead since there is no need to carry protocol information in each Protocol
Data Unit (PDU) payload.
• LLC/ENCAPSULATION: More than one protocol can be carried over the same VC. This
is available only when you select PPPoA in the Encapsulation field.
• LLC/SNAP-ROUTING: In LCC encapsulation, an IEEE 802.2 Logical Link Control (LLC)
header is prefixed to each routed PDU to identify the PDUs. The LCC header can be
followed by an IEEE 802.1a SubNetwork Attachment Point (SNAP) header. This is
available only when you select IPoA in the Encapsulation field.
Select UBR Without PCR or UBR With PCR for applications that are non-time sensitive,
such as e-mail.
Select CBR (Continuous Bit Rate) to specify fixed (always-on) bandwidth for voice or data
traffic.
Select Non Realtime VBR (non real-time Variable Bit Rate) for connections that do not
require closely controlled delay and delay variation.
Select Realtime VBR (real-time Variable Bit Rate) for applications with bursty connections
that require closely controlled delay and delay variation.
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.This
field is not available when you select UBR Without PCR.
The Sustainable Cell Rate (SCR) sets the average cell rate (long-term) that can be
transmitted. Type the SCR, which must be less than the PCR. Note that system default is 0
cells/sec.
This field is available only when you select Non Realtime VBR or Realtime VBR.
Maximum Burst Size (MBS) refers to the maximum number of cells that can be sent at the
peak rate. Type the MBS, which is less than 65535.
This field is available only when you select Non Realtime VBR or Realtime VBR.
VMG8924-B10A and VMG8924-B30A Series User's Guide