Local-Area Networks and LAN Switching - CCIE Routing and Switching Exam Certification Guide - page 112

The minimum frame size on Ethernet is 64 bytes, and the maximum is 1518 bytes. When
calculating the frame size, do not include the preamble in the summation. The Ethernet V2
frame format conforms to the following specification:
•

The minimum frame size is 6 + 6 + 2 + 46 + 4 = 64 bytes

•

The maximum frame size is 6 + 6 + 2 + 1500 + 4 = 1518 bytes

Novell 802.3 Raw Frame Format
Prior to the IEEE 802.3 specification, Novell needed a frame format for their NetWare
Internetwork Packet Exchange (IPX) network operating system. Novell produced their own
frame format to run on CSMA/CD networks.

Figure 4-3 shows the Novell 802.3 raw frame format. The frame field descriptions are displayed
in Table 4-2.

Novell 802.3 Raw Frame Format

Figure 4-3

Data + pad
46-1500 bytes

Preamble
8 bytes

DA
6 bytes

SA
6 bytes

Length
2 bytes

FCS
4 bytes

FFFF

Novell 802.3 Raw Frame Fields Descriptions Table 4-2

Field Description

Preamble Same as with Ethernet V2; a string of binary 1s and 0s ending with 11

Destination Address (DA) 48-bit MAC address of the destination host

Source Address (SA) 48-bit MAC address of the host that sent the frame (source host)

Length Contains the length of the data field in binary; indicated values are from

3 to 1500 bytes

Data Contains ULP IPX information

Frame Check Sequence (FCS) Contains the 32-bit cyclic redundancy check (CRC) for error detection

Novell frames are unique in that the data field begins with an FFFF hex (at the beginning of the
IPX protocol header).

IEEE 802.3 Frame Format
The IEEE produced its Ethernet standard in June 1983. The type field changed to a length field
and the IEEE 802.2 LLC layer was added.