Computer Networks: Protocols, Technologies, and Concepts
Internet Access Technologies
Dial up – phone; DSL – phone line; Cable Internet – TV Network
Delay Calculations
Propagation delay, transmission delay, store-and-forward, Bandwidth-delay product, Bandwidth-RTT product, Dnodal=dproc+dqueue+dtrans+dprop; Dtrans = L/R, L = length, R = bandwidth/rate; Dprop = d/s, d = length, s = propagation speed.
ISO/OSI Reference Model
Seven layers; TCP/IP architecture for the Internet (five layers)
Traceroute/Tracert
3 delay measurements for each router on the way to destination, last one is destination
HTTP
Persistent vs. Non-persistent
Email Application Protocols
SMTP, POP, IMAP; their underlying transport layer protocol
HTTP Request Methods
GET, POST, DELETE, HEAD, PUT
HTTP Response Status Codes
200 OK, 301 Moved permanently, 400 bad request, 404 not found, 505 HTTP version not supported
HTTP Cookie
User visits site, cookie id assigned
Web Caching
Proxy server deployed closer to clients
DNS Resource Records
How to interpret a resource record of a given type (A, NS, CNAME, MX)
Rdt (Reliable Data Transfer)
Channel error characteristics & mechanisms to handle channel errors
Sliding Window Protocols
Go-Back-N; Selective Repeat
TCP & UDP Segment Format
IP addresses, TCP port numbers, TCP sequence numbers
TCP Acknowledgement Number
Connection management scenario and general scenario
TCP Fast Retransmit
Behavior and implications
TCP Flow Control
Receiver notifies sender of free buffer space
TCP Congestion Control
Adjustment in Slow Start, Congestion Avoidance, and Fast Recovery states
MSS & MTU
Relationship between MSS and MTU
IPv4 & IPv6 Datagram Format
Address format, datagram format
Longest Prefix Matching
Convert range on forwarding table into prefix
Subnetting
Process and CIDR
IPv4 Datagram Fragmentation
Reassembled only at final destination
NAT
Network address translation
IP Tunneling
Transition to IPv6
DHCP
Dynamic host configuration protocol
Routing Algorithms
Link state algorithm, distance vector algorithm
Inter-AS Routing (BGP)
When routers use eBGP & iBGP sessions/connections
ICMP
Internet control message protocol
MAC Protocols
Channel partitioning, random access, taking turns
Binary Exponential Back-off in CSMA/CD
After the Nth collision
LAN Broadcast vs. Unicast
Comparison and usage
ARP Protocol
Finding the MAC address for a given IP address in the LAN
Ethernet Switch Self-Learning Mechanism
Switch learns hosts can be reached through which interfaces
MAC & IP Address Settings
During the process of sending a datagram from one subnet to another subnet
Hidden Terminal Problem
In a wireless setting
Comparison between Ethernet & WiFi
In terms of MAC address format, frame format, MAC protocol, etc.
Mobility Management
When a node moves from one access network to another access network