mocks dont know

variables make sense names of subroutine tells the reader what it it makes code easier to understand makes code easier to debug and maintain

• each subroutine can be tested separately - making it easier to debug • many programs can work on a large program once - cutting down development time (splitting it up) • subroutines can be reused - reducing development time • code broken down into meaningful subroutines - easier to maintain

POSITION(word, ‘r’) word.index(‘r’) word.find(‘r’) finds position of a letter

slices a string • SUBSTRING(start, end, str) e.g. word = algorithm SUBSTRING (3,6,word) = “orit” • print(word[3:7]) (stops

it is a named out of line block of code that may be executed by writing its name in a program statement

binary - in order - start at middle - halve set, compare middle item then discard one side, repeat - suitable for a large no. items - new items added in the correct place not end

installed on users computer without their knowledge or permission, to do harm can copy itself automatically

pretends to be of a helpful use to the user but is really malicious may spread malware, crash computer, corrupt data, access sensitive info

software that gathers info about a person or an organisation without their knowledge can collect personal info such as logins

monitors incoming/ outgoing network traffic decides what to block/allow based on rules can block certain IP addresses or ports

determines which devices are allowed to access a network by whitelisting certain permitted devices (identified by their MAC address)

where network applications operate data is encoded - HTTP, HTTPS, FTP, IMAP, SMTP

sets up communication between two hosts and establishes settings eg language and packet size splits data into packets - TCP and UDP

where network hardware is located eg NIC and OS device drivers attaches MAC addresses of the sender/ receiver

addresses packages for transmission routes packages across the network attached IP address of sender and destination - IP

A T I L

family of related protocols communicate by sending each other individual data frames the MAC address specifies the source and destination of each frame

allows electronic devices to connect to a WLAN the Wireless Access Point receives data from a network the transmitter converts this into radio waves which are received by a device

defines how messages are broken into packets and reassembled detected errors and resends lost packets

connectionless transmission model can send messages to other hosts on an IP network like TCP but has no error checking and maintains an open connection - gaming/ streaming

identifies the location of the device on a network (the internet) and routes the packets from source to destinations via routers

used to transfer files between a client and server. based on a client server model and uses separate control and data connections between the client and server

for sending emails between servers over the internet

receiving email stores email on server but allows user to view it on many devices