Week 7 - Networks And Distributed Architectures Flashcards
What is the idea behind networks and distributed architectures?
Machines powering our software resides in different places now. There is a separation between physical and software applications
What are examples of local area networks?
LAN: ethernet (wired) cabled network or wi-if (wireless)
What is an ethernet
Shared wired connection
What is a wi-if
Shared radio channel
Why are LAN’s useful?
You can isolate them from external networks and you can manage different components of the network.
What are the benefits and shortcomings to wi-fi
[+] Flexibility of connecting from anywhere. You don’t need specific, designated end-points
[-] can be interfered with
What are the benefits of ethernet?
[+] faster connection
What is an IP address and why do you need it?
IP stands for internet protocol. It’s an address so that the sender knows who is requesting and receiving the packet.
What is a feature of the IP address?
It needs to be unique and depends very much on the level of network. For example, there is an IP address for nodes at the global network, centralised network and local network.
What are the benefits of distribute architectures
You get to manage information at different levels - parcelling them at higher or lower levels.
What is my IP (at different levels)
ISP assigned IP - SMU’s IP for connection to ISP
Locally assigned IP - SMU assigns IP for each user
How does the packet travel?
Message sent to SMU’s ISP first then the router decides who is the receiver
How does information travel?
Data is exchanged on computer networks in packets. The data is split up and the packets are sent out individually, they get routed and switched around.
How does the internet work?
The network is connected to other networks, till the point that everyone is connected at some point. This is why the internet is described as distributed.
Why is the internet distributed architecture?
There is no central authority controlling the internet. You can connect as a node and have access to the network to send something from one IP to another IP
How to ensure standards?
Protocols on open source need to be agreed upon. The standards reflect the standard way of communicating.
How is the internet different from the web
The internet is the network, the connection itself;
The web is the part of the internet with which you can access resources (HTML access through URL)
How do these resources become accessible?
Search engines
What are intranets?
They form part of the deep web and restrict access to search engines. Because these pages are not indexed. They are connected to the internet but not discoverable by google search.
What is the dark web?
It forms the part fo the web that is undiscoverable by search engines and intentionally hidden from general access. You will need special tools to access the dark web.
What is the goal of the dark web
To anonymise information, the sender and receiver of the messages
How does the dark web achieve anonymization?
they use a different protocol
What does a VPN do?
A VPN allows you to connect to a main server and route all traffic through that server so it looks like its coming from the VPN.
What are the concerns of VPN
Raises privacy issues and questions surrounding reliability. VPN’s may still be subject to production orders
