Below are the things I was looking for in your assignment. Each group has a file similar to this one, showing some notes and scores. A + means a good thing and - means bad (e.g. something missing or incorrect)

TASK A EXPLAIN WIRELESS LANS [30]
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A1 TYPICAL TOPOLOGY
+ infrastructure mode is the typical topology
+ Station (e.g. laptop) connects wirelessly to an Access Point. That AP then connects usually via wires to another network (e.g. LAN)

A2 DISCOVER JOIN TRANSFER
+ Discovery is either passive (via beacons) or active (by probe requests and responses)
+ Joining involves authentication and association
+ Data transfer is normally via DCF (see CSMA/CA)

A3 PROTOCOL STACKS
+ IEEE 802.11 focusses on physical layer and data link layer, where the data link layer is divided into Logical Link Control and MAC
+ APs don't need higher layers, but laptops/stations normally also have Network, Transport and Application layer

A4 STANDARDS
+ IEEE is the standards organisation
+ IEEE 802 is a family of LAN/MAN standards
+ IEEE 802.11 is group of wireless LAN standards
+ 11a, 11b, 11g, 11n standardise different physical layers
+ 11e offers quality of service, 11i security, and many others

A5 PHYSICAL LAYER
+ Should give typical values of the following for each of the physical layers (a b g n)
+ Frequency, data rates, distance, transmit power, channels

A6 CSMA/CA
+ For data transfer a station senses the medium before transmitting
+ If no one else is transmitted (the medium is idle) then the station waits for a DIFS and then Backoff
+ Then the station transmits DATA and the receiver responds with an ACK
+ If however the medium was busy (someone else transmitting) the station will defer/wait until the medium becomes idle again and try again

SCORE: 


TASK B CAPTURE TRAFFIC [25]
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(Most students used my provided capture so B1 and B3 are not relevant)

B1 SETUP


B2 TIME SEQUENCE DIAGRAMS
+ Should show the DNS exchange, TCP connection setup, HTTP GET request, TCP ACKs and HTTP 200 ok

B3 PRINTOUT/SCREENSHOT/FILE


B4 PACKET DIAGRAMS
+ Should show packet structure like: IEEE802.11 | IP | TCP | HTTP
+ Some header fields and header sizes is also useful

B5 EXPLANATION
+ User enters in URL in address bar of browser
+ DNS is used: client asks DNS server for IP address for given domain name
+ DNS server responds with IP address
+ Now web browser sends HTTP GET request to web server at that IP address
+ HTTP 200 ok comes back carrying the web page

SCORE:


TASK C MEASURE THROUGHPUT [30]
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C1 SETUP
+ Should give details of computer used, epsecially 11a or 11b or 11n or ...
+ Data rate used for experiments is important

C2 RESULTS
+ Throughput results should be shown in table or plot
+ Important to give correct units, e.g. Mb/s
+ Efficiency can also be given, where it is: throughput/datarate
+ I expected in many cases the efficiency will be about 30 to 50%

C3 EXPLANATION
+ Why is efficiency about 30-50%?
+ CSMA: For every data frame to be sent the station must wait for DIFS, wait for Backoff, then transmit data frame and header, then wait for SIFS and ACK
+ Station spends lot of time waiting, but not transmitting real data, hence lower efficiency
+ Also the header of the IEEE 802.11 frame, IP datagram, TCP segment must be included, ie. it is not real data
+ Finally in some cases if there are other computers transmitting at the same time, your computer must wait even longer, leading to even lower efficiency

SCORE:


PRESENTATION AND WEBSITE [15]
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+ Most groups created an basic website and received full marks for presented
+ However few, if any of the websites were 'eye-catching'. They all looked the same with a header of:
Home | Explain Wireless LANS | Capture | Throughput | About Group
+ No-one made use of links in the web pages

SCORE:


COMMENTS OR BONUS [25]
======================
+ Two or three groups had descriptions or results which were much better than other groups and received a bonus
+ For groups that had just 2 members, I gave them higher scores for the same quality of work as a group with 3 members
SCORE: 0


TOTAL [100]
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+ Recall the assignment is worth 15% of total course grade
SCORE: