The Internet Architecture Flashcards
What is a host?
a computer connected to a computer network
What is a LAN?
A local area network (LAN) consists of a switching device, to which hosts are directly connected
What is a WAN?
A wide area network (WAN) consists of connected switching devices, to which local area networks are directly connected
Key connection technologies of the internet
twisted-pair cables;
fibre-optic cables;
terrestrial radio channels;
satellite radio channels
what is a twisted-pair cable?
A twisted-pair cable consists of four pairs of copper wires twisted together in a shielded cable. Bandwidth CAT5e = 10 ×100Mbps.
What is a fibre-optic cable?
A fibre-optic cable consists of a bundle of light-conducting fibres in a shielded cable. Bandwidth OC-768 = 768 ×51.8Mbps
What is a terrestrial radio channel?
A terrestrial radio channel links two-or-more mobile stations via a base station. Bandwidth WiFi 802.11n = 270Mbps
What problems are there with using terrestrial radio channels for computer networking?
when they interfere with each other it slower wifi down
less secretive
What is a satellite radio channel?
satellite radio channel links two-or-more ground stations via a geostationary satellite. Bandwidth Eutelsat = 3.6Mbps (download); 384Kbps (upload)
There are two kinds of switching device:
1 switches;
2 routers.
What is a switching device?
A switch is a special-purpose hardware device dedicated to interconnecting hosts using the same packet (or segment)
format.
What do switches do?
Switches dynamically sense the Media Access Control (MAC) to port mapping
What is a router?
A router is a special-purpose hardware device dedicated to interconnecting networks that may use different technologies, addressing schemes or packet formats
What do routers do?
Routers periodically exchange forwarding tables which
contain a valid next-hop route for each possible destination address
What are protocols organized into and why?
Network designers organize protocols into layers to make them easier to design, build and maintain
