ZyXEL Communications P-2812HNU-51c manual 104

Chapter 5 WAN Setup

The following table describes the fields in this screen.

Table 19 Layer 2 Interface Configuration

LABEL	DESCRIPTION
ATM PVC	VPI (Virtual Path Identifier) and VCI (Virtual Channel Identifier) define
Configuration	a virtual circuit. This section is available only when you configure an
	ATM layer-2 interface.
VPI	The valid range for the VPI is 0 to 255. Enter the VPI assigned to you.
VCI	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.
Select DSL Link	Select EoA (Ethernet over ATM) to have an Ethenet header in the
Type	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.
	Select PPPoA (PPP over ATM) to allow just one PPPoA connection over
	a PVC.
	Select IPoA (IP over ATM) to allow just one RFC 1483 routing
	connection over a PVC.
Encapsulation	Select the method of multiplexing used by your ISP from the drop-
Mode	down list. Choices are:
	• VC/MUX: In VC multiplexing, each protocol is carried on a single
	ATM virtual circuit (VC). To transport multiple protocols, the P-
	2812HNU-51c 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 Select DSL Link Type 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 Select DSL Link Type
	field.
	• 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 EoA in the
	Select DSL Link Type field.
Service Category	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 Realtime VBR (real-time Variable Bit Rate) for applications
	with bursty connections that require closely controlled delay and delay
	variation.
	Select Non Realtime VBR (non real-time Variable Bit Rate) for
	connections that do not require closely controlled delay and delay
	variation.

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	P-2812HNU-51c User’s Guide