Acronyms and Concepts Flashcards
What is CBC
Cipher Block Chaining - used to eliminate the need for a ‘random key’ when encrypting using Block Ciphers.
What is RSA
Asymmetric (Public-Private key) Encryption Algorithm
What is KDC
Key Distribution Centre
What is PGP
Pretty Good Privacy: a combination of both symmetric and asymmetric cryptography.
Key idea: to use public key encryption to distribute symmetric keys.
What is MAC (Encryption)
Message Authentication Code: A hash of the message + symmetric key that you send to the receiver.
What is Digital Signiture
Encrypt the hash with your private key instead and send along with the original message.
What is CA (Encryption)
Certification Authority.
What is DSL
Digital Subscriber Line
What is HFC
Hybrid Fiber Coaxial. Refers to neighbourhood line to the cable headend being made up of Fiber. Pretty much the BUS is made up of Fiber.
What is TP
Twister Pair. Makes use of two insulated copper wires, which are twisted to reduce interference.
What is FDM
Frequency Division Multiplexing.
Key idea: divide the channel based on frequency and total number of users.
What is TDM
Time Division Multiplexing.
Key idea: divide the channel based on time and total number of users.
Explain Packet Switching
Purpose: Allow more users to use a network at once
IXP
Internet Exchange Point. Where all ISP’s can connect, so that they may exchange data (Level 1 ISPS).
CDN
Content Distribution Networks.
What is POP
Point of Presence. The two end points of links between ISPs.
AIMD (Congestion Control)
Additive Increase Multiplicative Decrease.
Key idea: to make full use of bandwidth without over congesting the network, sender should continually increase the transmission rate (window size), until the first packet is dropped - at which point the packet size should be halved and the process should be repeated.
HOL (Blocking)
Head of the Line.
The packet at the front of the buffer prevents previous packets from going to their respective output port, even though they’re destination port is not being used.
MTU
Maximum Packet Transfer Size
IP Fragmentation
Dividing packets too large for a network into smaller packets instead.
CIDR
Classless Inter Domain Routing
DHCP
Dynamic Host Configuration Protocol
NAT
Network Address Translation
RIP
Routing Information Protocol.
Based off of distance vector algorithm.
OPSF
Open Shortest Path First.
Based off Dijkstra’s algorithm.
What is BGP
Border Gateway Protocol
What is CRC
Cyclic Redundancy Check
CDMA
Code division multiple access.
Key idea: splitting the channel based on codes allocated to devices.
What is CSMA
Carrier Sense Multiple Access.
What is CSMA/CD
Collision Detection (Wired)
What is CSMA/CA
Collision Avoidance (Wireless)
What is RTS
Request to Send.
What is CTS
Clear to Send
