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Sets with similar termsVerified questionsCOMPUTER SCIENCE
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COMPUTER SCIENCE
For the MIPS assembly instructions below, what is the corresponding C statement? Assume that the variables f, g, h, i, and j are assigned to registers $s0,$s1, $s2,$s3, and $s4, respectively. Assume that the base address of the arrays A and B are in registers$s6 and $s7, respectively.$ $$ \begin{array} { l l } sll \quad $$ t0, $s0, 2 \quad \# \quad$t0 = f \ast 4 add $t0,$s6, $t0 \quad \# \quad$t0 = \&A[f] sll $t1,$s1, 2 \# $t1 = g \ast 4 \\ add \quad$t1, $s7,$t1 \# $t1 = \&B[g] \\ lw \quad$s0, 0\left($t0\right) \quad \# \quad f = A[f] \\ addi \quad$t2, $t0, 4 \\ lw \quad$t0, 0\left($t2\right)\\ add \quad$t0, $t0,$s0 sw $t0, 0\left($t1\right) $\end{array}$
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COMPUTER SCIENCE
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COMPUTER SCIENCE
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Recommended textbook solutions
stands for virtual LAN.
Explanation.
It's a technique that lets you have multiple logical LANs operating on the same physical equipment. Any frame with a VLAN tag will only be delivered out of a switch interface configured to relay that specific tag. This way you can have a single physical network that operates like it's multiple LANs. VLANs are usually used to segregate different forms of traffic. So you might
see a company's IP phones operating on one VLAN, while all desktops operate on another. After this, you'll find a data payload of an Ethernet frame. A payload in networking terms is the actual data being transported, which is everything that isn't a header. The data payload of a traditional Ethernet frame can be anywhere from 46 to 1500 bytes long. This contains all of the data from higher layers such as the IP, transport and application layers that's actually being transmitted. Following that
data we have what's known as a frame check sequence. This is a 4-byte or 32-bit number that represents a checksum value for the entire frame. This checksum value is calculated by performing what's known as a cyclical redundancy check against the frame. A cyclical redundancy check or CRC, is an important concept for data integrity and is used all over computing, not just network transmissions. A CRC is basically a mathematical transformation that uses polynomial division to create a number that
represents a larger set of data. Anytime you perform a CRC against a set of data, you should end up with the same checksum number. The reason it's included in the Ethernet frame is so that the receiving network interface can infer if it received uncorrupted data. When a device gets ready to send an Internet frame, it collects all the information we just covered, like the destination and originating MAC addresses, the data payload and so on. Then it performs a CRC against that data and attaches
the resulting checksum number as the frame check sequence at the end of the frame.
This data is then sent across a link and received at the other end.
Here, all the various fields of the Ethernet frame are collected and now the receiving side performs a CRC against that data.
If the checksum computed by the receiving end doesn't match the checksum in the frame check sequence field, the data is thrown out. This is because some amount of data must have been lost or corrupted during
transmission. It's then up to a protocol at a higher layer to decide if that data should be retransmitted. Ethernet itself only reports on data integrity. It doesn't perform data recovery.
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