LevelOne GEP-0950 - Manual (Page 22)

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SSAP, Control and Information. The DSAP address field identifies the one or more
service access points, in which the I/G bit indicates it is individual or group address.
If all bit of DSAP is 1s, it’s a global address. The SSAP address field identifies the
specific services indicated by C/R bit (command or response). The DSAP and
SSAP pair with some reserved values indicates some well-known services listed in
the table below.
0xAAAA SNAP
0xE0E0 Novell IPX
0xF0F0 NetBios
0xFEFE IOS network layer PDU
0xFFFF Novell IPX 802.3 RAW packet
0x4242 STP BPDU
0x0606 IP
0x9898 ARP
LLC type 1 connectionless service, LLC type 2 connection-oriented service
and LLC type 3 acknowledge connectionless service are three types of LLC frame
for all classes of service. In the figure above, it shows the format of Service Access
Point
3-3 SAP Format
(SAP). Please refer to IEEE802.2 for more details.