IEEE 802.3as-2006 pdf free.IEEE Standard for Information technology-Telecommunications and information exchange between systems—Local and metropolitan area networks – Specific requirements. Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications Amendment 3: Frame format extensions.
A MAC frame is encapsulated in a packet by the MAC. This section describes in detail the fields of the MAC frame and the additional fields that the MAC creates to encapsulate the MAC frame. These fields arc described in order of transmission.
change subclause 3.2.1 as follows:
3.2.1 Preamble field
The preamblePreamble field is a 7-octet field that is used to allow the PLS circuitry to reach its steady-state synchronization with the received picket’s timing (see 4.2.5).
Change ,suhclause 3.2.2 as follows:
3.2.2 Start Frame Delimiter (SFD) field
The SFD field is the sequence 10101011. It immediately follows the preamble pattern. A MAC frame starts immediately after the SFD.
change the first paragraph of suhclause 3.2.3 as follows:
3.2.3 Address fields
Each MAC frame shall contain two address fields: the Destination Address field and the Source Address field, in that order. The Destination Address field shall specify the destination addressee(s) for which the MAC frame is intended. The Source Address field shall identify the station from which the MAC frame was initiated. The representation of each address field shall be as follows (see Figure 3—2):
Change subelause 3.2.4 as follows:
3.2.4 Destination Address field
The Destination Address field specifies the station(s) for which the MAC frame is intended. It may be an individual or multicast (including broadcast) address.
Chang’ .suhclause 3.2.5 as follows:
3.2.5 Source Address field
The Source Address field specifics the station sending the MAC’ frame. The Source Address field is not
interpreted by the CSMAGD MAC sublayer.
change subcla use 3.2.6 as follows:
3.2.6 LengthlType field
This two-octet field takes one of Iwo meanings, depending on its numeric value. For numerical evaluation. the first octet is the most significant octet of this field.IEEE 802.3as pdf download.