SNR S2940-8G-v2, Configuration Manual

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SNR S2940-8G-v2 Switch Configuration Guide
PPPoE Intermediate Agent Configuration
PPPoE Intermediate Agent vendor tag Frame
The following is the format of tag added by PPPoE IA, adding tag is the Uppermost function of
PPPoE IA.
0x0105 (Vendor-Specific) TAG_LENGTH
0x00000DE9 (3561 decimal, i.e. ADSL Forum IANA entry)
0x01 Agent Circuit ID value... length
Agent Circuit ID value (con t) ...
0x02 Agent Circuit ID value... length
Agent Circuit ID value (con t) ...
Figure 54.3: PPPoE IA - vendor tag (4 bytes in each row)
Add TLV tag as 0x0105 for PPPoE IA, TAG_LENGTH is length field of vendor tag; 0x00000DE9
is 'ADSL Forum' IANA entry of the fixed 4 bytes; 0x01 is type field of Agent Circuit ID, length is
length field and Agent Circuit ID value field; 0x02 is type field of Agent Remote ID, length is length
field and Agent Remote ID value field.
PPPoE IA supplies a default circuit ID value, the default circuit ID (The figure in the following)
includes 5 fields, ANI (Access Node Identifier) can be configured by user, it's length is less than 47
bytes. If there is no ANI configured, MAC is accessed by default, occupy 6 bytes and use space
symbol to compart, 'eth' occupies 3 bytes and uses space symbol to compart, 'Slot ID' occupies 2
bytes, use '/' to compart and occupy 1 byte, 'Port Index' occupies 3 bytes, use ':' to compart and
occupy 1 byte, 'Vlan ID' occupies 4 bytes, all fields use ASCII, user can configure ciucuit ID for
each port according to requirement.
ANI
(n byte)
Space
(1 byte)
Eth
(3 byte)
Space
(1 byte)
Slot ID
(2 byte)
/
(1 byte)
Port Index
(3 byte)
:
(1 byte)
VLAN ID
(4 byte)
Figure 54.4: Agent Circuit ID value
MAC of the access switch is the default remote ID value of PPPoE IA. remote ID value can be
configured by user flexibly, the length is less than 63 bytes.
Trust Port of PPPoE Intermediate Agent
Discovery stage sends five kinds of packets, PADI and PADR packets sent by client to server,
PADO and PADS packets sent by server to client, PADT packet can be sent by server or client.
In PPPoE IA, for security and reduce traffic, set a port connected server as trust port, set ports
connected client as untrust port, trust port can receive all packets, untrust port can receive only
PADI, PADR and PADT packets which are sent to server. To ensure client operation is correct, it
must set the port connected server as trust port, each access device has a trust port at least.
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