|urvijaykumar please review below:|
1. Wireless has a lot of overhead. This means the data payload is smaller than wired.
2. The channel width is 100mbps. Problem is there is a lot of different processes talking on this bandwidth. Your file transfer isn't the sole operation of the network. It can never be because of the nature of CSMA/CD
3. You have to consider all the links in the chain between your laptop hard drive and that of the NAS unit hard drive. There are a number of systems that affect the throughput from one end to another.
Only do wired if you want the fastest transfer
Consider FTP to the NAS as a possible or better option
Use Winzip to compress the file then xfer over.
Get a gigabit nas and router.