ZyXEL Communications MES3500-24, User Manual

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Chapter 31 PPPoE
MES3500-24/24F User’s Guide
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The 1 in the first field identifies this as an Agent Circuit ID sub-option and 2 identifies this as an
Agent Remote ID sub-option. The next field specifies the length of the field. The Switch takes the
Circuit ID string you manually configure for a VLAN on a port as the highest priority and the Circuit
ID string for a port as the second priority. In addition, the Switch puts the PPPoE client’s MAC
address into the Agent Remote ID Sub-option if you do not specify any user-defined string.
31.1.2.1 Flexible Circuit ID Syntax with Identifier String and Variables
If you do not configure a Circuit ID string for a VLAN on a specific port or for a specific port, the
Switch adds the user-defined identifier string and variables into the Agent Circuit ID Sub-option.
The variables can be the slot ID of the PPPoE client, the port number of the PPPoE client and/or the
VLAN ID on the PPPoE packet.
The identifier-string, slot ID, port number and VLAN ID are separated from each other by a pound
key (#), semi-colon (;), period (.), comma (,), forward slash (/) or space. An Agent Circuit ID Sub-
option example is “Switch/07/0123” and indicates the PPPoE packets come from a PPPoE client
which is connected to the Switch’s port 7 and belong to VLAN 123.
31.1.2.2 WT-101 Default Circuit ID Syntax
If you do not configure a Circuit ID string for a specific VLAN on a port or for a specific port, and
disable the flexible Circuit ID syntax in the PPPoE > Intermediate Agent screen, the Switch
automatically generates a Circuit ID string according to the default Circuit ID syntax which is
defined in the DSL Forum Working Text (WT)-101. The default access node identifier is the host
name of the PPPoE intermediate agent and the eth indicates “Ethernet”.
31.1.3 Port State
Every port is either a trusted port or an untrusted port for the PPPoE intermediate agent. This
setting is independent of the trusted/untrusted setting for DHCP snooping or ARP inspection. You
can also specify the agent sub-options (circuit ID and remote ID) that the Switch adds to PADI and
PADR packets from PPPoE clients.
Table 95
PPPoE IA Remote ID Sub-option Format
SubOpt Length Value
0x02
(1 byte)
N
(1 byte)
MAC Address or String
(63 bytes)
Table 96
PPPoE IA Circuit ID Sub-option Format: Using Identifier String and Variables
SubOpt Length Value
0x01
(1 byte)
N
(1 byte)
Identifier
String
(53 byte)
delimiter
(1 byte)
Slot ID
(1 byte)
delimiter
(1 byte)
Port No
(2 byte)
delimiter
(1 byte)
VLAN ID
(4 bytes)
Table 97
PPPoE IA Circuit ID Sub-option Format: Defined in WT-101
SubOpt Length Value
0x01
(1 byte)
N
(1 byte)
Access
Node
Identifier
(20 byte)
Space
(1
byte)
eth
(3
byte)
Space
(1
byte)
Slot
ID
(1
byte)
/
(1
byte)
Port No
(2
byte)
:
(1
byte)
VLAN
ID
(4
bytes)