User`s guide

Signamax 065-7931 16-Port 10/100/1000BaseT/TX WebSmart Switch
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Table 3-1 is the format of the LLC PDU. It is comprised of four fields: DSAP,
SSAP, Control and Information. The DSAP address field identifies one or more
service access points, in which the I/G bit indicates if it is an individual or group
address. If all bits of the DSAP are 1s, it is a global address. The SSAP address
field identifies the specific services indicated by the C/R bit (command or response).
The DSAP and SSAP pair with some reserved values to indicate 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
Table 3-2
LLC type 1 connectionless service, LLC type 2 connection-oriented service
and LLC type 3 acknowledge connectionless service are three types of LLC frames
used for all classes of service. In Fig 3-2, the format of the Service Access Point
(SAP) is shown). Please refer to IEEE 802.2 for more details.
Table 3-1 LLC Format