Scientist interview questions shared by candidates
What is the size of Ethernet packet frames and why is it so? How does it help synchronization?
1585 bytes for synchronization (Couldn't answer why the exact number)
A data packet on the wire is called a frame . The frame ends with a 32-bit which is used to detect corruption of data in transit. Types OF Ethernet There are 3 types of Ethernet available in the market right now. 1. Traditional Ethernet – 10 Mbps 2. Fast Ethernet – 100 Mbps 3. Gigabit Ethernet – 1000Mbps A general requirement for SyncE was that any NE should have at least two reference clocks, and in addition, Ethernet interfaces must be able to generate their own synchronization signal in case they lose their external reference. If such is the case, it is said that the Ethernet Node (EN) is in holdover. The synchronous signal must be filtered and regenerated by PLL at the Ethernet nodes since it degrades when passing through the network.
Size of ethernet frame is ranges from 72 to 1526 bytes and in the the frame structure first field preamble which is of size 7 bytes and second field start frame delimiter(SFD) which of size 1 byte are used for the sychronization between sender and receiver. SFD bit format is xx110011 which indicate the start of actual data.So that by getting those bits the receiver is alert and receiver the actual data without any problem.