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What is the EtherType in the Ethernet frame of the ARP request?
EtherType is a two-octet field in an Ethernet frame. It is used to indicate which protocol is encapsulated in the payload of the frame and is used at the receiving end by the data link layer to determine how the payload is processed. The same field is also used to indicate the size of some Ethernet frames.
What is the length of the Ethernet 2 frame that contains the Ethernet header?
Structure
| Layer | Preamble | Ethertype (Ethernet II) or length (IEEE 802.3) |
|---|---|---|
| 7 octets | 2 octets | |
| Layer 2 Ethernet frame | ← 64–1522 octets → | |
| Layer 1 Ethernet packet & IPG | ← 72–1530 octets → |
How can a receiver distinguish between an Ethernet II frame and an IEEE 802.3 frame?
The biggest difference between Ethernet II and 802.3 is the fields of their Ethernet headers. The important distinction between Ethernet 2 and IEEE frames is that the Type field in Version II has been replaced with a 2-byte Length field in the IEEE formats.
What are the two sizes minimum and expected maximum of an Ethernet frame?
The minimum Ethernet frame size is 64 bytes, and the expected maximum is 1518 bytes. The frame size might be larger than that if additional requirements are included, such as VLAN tagging.
How big is MTU for Layer 2 Ethernet?
Meanwhile, the standard MTU for Layer 2 Ethernet frame is 1518 bytes ( 6 bytes source MAC + 6 bytes destination MAC + 2 bytes EtherType + 1500 bytes IP packet + 4 bytes Frame Check Sequence). For the Dot1Q trunk frame, extra 4 bytes for Dot1Q tag is added.
How is the MTU is 65535 but Ethernet does?
If the frame’s payload size itself is maximum of 1472 bytes (as per my textbook), how can the packet size of IP be greater than that which here is 65535? I observed that send returns -1 on i > 65507 and recv prints or receives a packet of maximum of length 65507.
How many bytes are in the 802.11 MTU?
I suppose that the answer regarding mentioned “7981 bytes” is in the specs. The Frame Body field is of variable size.
Is the MTU a property of the network?
The MTU is often considered a property of a network link, and will generally refer to the layer 2 MTU. The limits at layer 3 are far higher (see below) and cause no issues.