A-Level Computing#BristolMet Session Objectives#13 MUST define
the term network protocol SHOULD describe what network protocols do
COULD explain why protocols are needed for computers to communicate
Create a network of raspberry pis and ping to test connection.
Slide 2
A-Level Computing#BristolMet Protocols The word protocol means
a set of rules. Therefore Network Protocol a set of rules or
standards that control the transmission of data between devices.
These rules will include that method of transmission (serial or
parallel, the bit rate, transmission modes (simplex, duplex, half)
and error checking. If using parity both computers would need to be
using even parity or odd. If there are any differences to any of
these rules then messages would be never be accepted.
Slide 3
A-Level Computing#BristolMet Protocol Layers Protocols are
organised into layers which link into each other. This means it is
possible to tweak individual layers without affecting the whole
network standard. Protocols can be divide into 2 parts: logically
based and physically based. What might these 2 parts consist of? As
you will see the logical rules that can be applied depend on the
physical rules (or infrastructure) that is already in place.
PhysicalLogical PhysicalLogical Wired or Wireless?Concerns the data
itself? If wired, what cable to use??Serial or parallel
transmission? Fibre optic, cat 5 e, coaxial etcWhat mode to be
used? Simplex etc If wireless, what frequency, channel etc? Bit
rate to send the data at and how much to send at a time. Error
checking method, parity, echo e
Slide 4
A-Level Computing#BristolMet Examples of Protocols There are
many protocols that have been developed over the years. TASK:
Create a table and research the meaning and application Of the
following protocols. ProtocolMeaningApplication DNS HTTP TCP/IP
TLS/SSL ProtocolMeaningApplication DNSDomain Name System Translates
domain names such as bristolmet.net into IP addresses HTTPHypertext
Transfer Protocol For copying files from one host to another.
TCP/IPTransmission Control Protocol/Internet Protocol Set of rules
that organise data transmission over the internet. TLS/SSLTransport
Layer Security/Secure Sockets Layer Cryptographic protocols
designed for secure communications
Slide 5
A-Level Computing#BristolMet Practical Investigation TASK:
Follow the making a network connectiom tutorials and attempt to
create a direct network connection to the internet using a laptop
(with wifi) and a raspberry pi. Answer the following questions:
1.What is the IP address of your raspberry pi 2.Explain what an IP
address is? 3.Discuss why you cannot connect a raspberry directly
to a network?