HP 200 Series Services And Applications page 102

Bridging Service
Encapsulation Filters
DSAP SSAP Control Organization Prot. Type Data
1 octet 1 octet 1 octet 3 octets 2 octets
Figure 35. SNAP Encapsulation
SNAP encapsulation (shown in figure 35) is an extension of 802.2 encapsula-
tion. It prefixes one octet of DSAP information, one octet of SSAP
information, one octet of control information, three octets of organizational
information, and two octets of upper-level protocol type information (some-
times called Ethernet type) to the frame. The SNAP structure is further
encapsulated within a MAC-level medium-specific 802.x frame.
Preamble
Destination Source
Length Data FCS
8 octets
6 octets 6 octets 2 Octets 46–1500 octets 4 octets
FFFF IPX Header NetWare Core Protocol Packet
Figure 36. Novell Proprietary Encapsulation
Novell proprietary encapsulation (shown in figure 36) prefixes an eight-octet
preamble, six octets of destination-address information, six octets of source-
address information, and two octets of frame-length information to the
unchecksummed IPX frame (indicated by a value of FFFF). It appends a
four-octet frame check sequence to the frame.
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