Ethernet Frame is a mode of transferring data packets on any Ethernet link. Data to be transferred, is converted into proper data packets and then framed into each, with measures to check errors. An Ethernet Frame is one such data frame, which has coded data, with series of data check sequences, delimiter, source and destination address, and other information for successful transmission and tracking of data packet. An Ethernet Frame, always begins with a preamble, delimiter start identifying start of complete data packet, with addresses of both destination and source.
After the address of destination and source, data comes next in an Ethernet Frame. This then has frame check sequence, to determine and correct errors in certain capacity. There are standard algorithms followed to check number of bits of errors and corrected, if only few bits are found to be in error, in an Ethernet Frame. Each of the field is designated certain size, and receiver end will always check each segment and modify errors, and identify them by following standard decoding algorithms. It is easier to decode segmented bits, than whole of the frame data. An Ethernet Frame has standard data packets, for faithful transmission as well as reception.
Every data is represented in 0 and 1′s in the end and transmitted, by placing them in their respective places in an Ethernet Frame. Actual converted data may be 46 to 1500 bytes and is located before the check sequence bits. The preamble, which is assigned 8 bytes or 64 bits, allocates two bits for frame delimiter in a standard Ethernet Frame. The destination and source address of Ethernet link is allocated a size of 6 bytes each. Since data length is not fixed, a field that determines data length is present in the frame. This information is divulged in 2 bytes of data. Frame check bits, or CRC bits for Ethernet Frame are allocated 4 bytes, which mark the end of frame.
Ethernet Frame
These data Ethernet Frames are then transmitted in Ethernet link different sending algorithms. It can be a Multicast, where every node in a network is transmitted this data packet. This is far more easier and does not require the sending link to remember network architecture. Data is forwarded to the destination link blindly, through Ethernet Frames. Data frame may have different sizes for allocation depending on Ethernet network. This variation may either be in check sequence frame algorithm used, or size of Preamble in Ethernet Frame.
For a 802.3 Ethernet Frame, the preamble size is restricted to 7bytes, with 1 byte for start of delimiter. Then address of destination and source links are given. There is an optional field of 4 bytes for 802.1Q tag, followed by data length field of 2 bytes. This field for Ethernet Frame also gives information about Ethernet type and data packet that is being transmitted. This is followed by data packets which can be 46 bytes to 1500 bytes. A Cyclic Redundancy check bit sequence of 4 bytes, are then attached along with a gap for inter-frame in the end of Ethernet Frame.