EXP Computer S200 用户手册
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Bridging
Bridge Filtering
DSAP Values
The DSAP is a 1-byte ID found in the LLC field (see Figure 37). You set this value
in the Protocol Value parameter of the Protocol Filter Table. Examples of DSAPs
include:
in the Protocol Value parameter of the Protocol Filter Table. Examples of DSAPs
include:
• IBM (04, 08,...)
• Banyan Vines (BC)
• Novell IPX (E0)
• IBM NetBIOS (F0)
Figure 37. Protocol ID DSAP Located in LLC Field
SNAP Protocol ID
The SNAP is five bytes and is also found in the LLC field. The first three bytes are
OUI and the last two bytes are the Protocol ID (Figure 38).
OUI and the last two bytes are the Protocol ID (Figure 38).
Figure 38. SNAP Protocol ID
The SNAP format is used to identify Ethernet and pre-IEEE 802 protocol IDs that do
not fit the 1-byte ID.
not fit the 1-byte ID.
DSAP SSAP Control
LLC Info
LLC Field
DSAP SSAP Control
5 Bytes
LLC Field
AA
AA
Type
2 Bytes
OUI
00 00 00
03
AA
= Indicates SNAP Format
03
= Unnumbered Information
OUI
= Organizationally Unique Identifier
Type = 2-Byte Protocol ID