Eternet Frame Types

Introduction
There are a variety of Ethernet Frame Types that may be observed in a Novell LAN environment. This depends upon the version of NetWare, and the applications employed.
NetWare 2.X   : Ethernet 802.3 (Raw)
                Ethernet II

NetWare 3.X   : Ethernet 802.3 (Raw)
                Ethernet II
                Ethernet 802.2
                Ethernet SNAP (Sub-Network Access Protocol)
Not all frame types can support all traffic variants. For example, NetWare IPX/SPX packets are usually transmitted by 802.3 (Raw) frames. In fact, the 802.3 frame type can only support IPX/SPX traffic. When TCP traffic is generated, the Ethernet II frame is often used. Some desktop LAN analyzers will employ SNAP frames.
Ethernet Frame Types
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Ethernet 802.3 (Raw)
This is the original (and default) frame type used by NetWare. IT CAN ONLY SUPPORT NOVELL IPX/SPX TRAFFIC! The frame is similar to that described in 802.3 except that it does not contain the Logical Link Control (LLC) information in the packet.
Preamble             : 8 bytes
Destination Address : 6 bytes
Source Address       : 6 bytes
Length Field         : 2 bytes
Data Field           : Between 46 and 1500 bytes
Pad Characters       : Variable, stuffs data field up to 46 bytes
Frame Check Sequence: 4 bytes
Min Frame Length     : 64 bytes
Max Frame Length     : 1518 bytes (not including Preamble)
Ethernet 802.2
This frame includes fields from 802.3 and 802.2 (Logical Link Control) and can support the Novell IPX/SPX and FTAM (File Transfer, Access, and Management) protocols. The frame parameters are identical to those listed above, EXCEPT that the first three bytes of the data field are used to indicate 802.2 header (LLC) information.
Preamble             : 8 bytes
Destination Address : 6 bytes
Source Address       : 6 bytes
Length Field         : 2 bytes
Data Field           : Between 46 and 1500 bytes (including LLC)
Pad Characters       : Variable, stuffs data field up to 46 bytes
Frame... [continues]

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