CPS 1 - Spring, 2000 - Ramm 4/5/00 #31
Chapt 11. Computer Communications
- The Layers
- The Physical Layer
- Hardware (e.g. Ethernet)
- The Ethernet Packet
- The IP (Internet Protocol) Layer
- The IP Packet
- Hardware Independence
- The TCP (Task Control Protocol) Layer
- The Application Layer
- Packets Within Packets
- Reliability
- Addressing (Layers Again!)
- Hardware Address (Ethernet Address)
- unique 6 octet (8 bit -- byte) number
- usually 6 groups of two hex digits: b3 fe 13 21 a5 41
- centrally administered
- IP Address
- 4 octet number: e.g. 128.109.40.1
- usually 4 decimal number separated by periods
- network part ;host part
- Centrally Administered
- Domain Name
- hierarchical system
- root: edu, com, mil, net, country
- hostname; suborg; organization
- e.g. oberon.cs.duke.edu
- person on host is e.g. ramm@oberon.cs.duke.edu
- Applications
- email
- news
- talk
- ftp
- anonymous
- archives
- free software
- weather servers
- forecasts
- weather maps
- finger
- telephone
- telnet
- rlogin
- irc
- information services
- Client/Server
- Print Server
- File Server
- Name Server
- WWW
- Computer Security / Confidentiality
- Basic Ideas
- Passwords
- Encryption
- Whole New Chapter on these Topics
Computer Security
- Important Topic
- Brief Case Combination Locks
- Briefcase combination lock
- Analysis
- number of wheels
- number of positions
- time per trial
- alternatives