Parts of a computer (don't need to study)
NIC's and how they work hardware/software
Different categories of internet access: Dialup, Cable, CHSI
TCP/IP and how it works
Ping, arp, tracert commands
convert binary, decimal, hexadecimal
MAC Address and logical address What are they used for and when?
IEEE 802 specifications
Coxial, Fiber media types
Twisted pair, cat 3, cat 5, cat 5e max lengths
Fiber optic mult imode and single mode
Define properties of a wave: Frequency, amplitude, phase, attenuation, signwave characteristics
What media is used for what application; backbone, distribution point, LAN
Hubs, repeaters, switches, routers, what they do and how
Client/Server and P2P network
RJ11 vs RJ 45
RJ 11 is used for phones, RJ 45 is used for ethernet
DCE and DTE Difference
DCE (Data Communications Equipment) and DTE (Data Terminal Equipment) are descriptions of the role an Ethernet interface. DCE is typically the upstream device (network end), and DTE the downstream device (user end). DTE is an end station, while DCE is a server, router, or hub.
- DTE-DCE or DCE-DTE connections use Standard Ethernet Cable (straight-thru)
- DTE-DTE or DCE-DCE connections use crossover Ethernet Cable (send/receive "cross over")
DCE/DTE refer to interfaces - not the actual device. A device can have both DCE and DTE ports. However, in general:
- PC LAN cards (NIC - Network Interface Card) are DTE
- Hub LAN ports are DCE
- Hub Uplink Ports are DTE - it is a shared port with the last LAN port, but has the pinouts crossed
- Cable Modem LAN port is DCE
- Router LAN ports are DCE
- Home Router WAN Ethernet ports are DTE
Major standard making bodies in networking: TIA/EIA, IEEE, ISO
OSI Reference Model
I use this mnemonic to remember it: PDNTSPA.
Application
This layer supports application and end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are considered, and any constraints on data syntax are identified. Everything at this layer is application-specific. This layer provides application services for file transfers, e-mail, and other network software services. Telnet and FTP are applications that exist entirely in the application level. Tiered application architectures are part of this layer.
Presentation
This layer provides independence from differences in data representation (e.g., encryption) by translating from application to network format, and vice versa. The presentation layer works to transform data into the form that the application layer can accept. This layer formats and encrypts data to be sent across a network, providing freedom from compatibility problems. It is sometimes called the syntax layer.
Session
This layer establishes, manages and terminates connections between applications. The session layer sets up, coordinates, and terminates conversations, exchanges, and dialogues between the applications at each end. It deals with session and connection coordination.
Transport
This layer provides transparent transfer of data between end systems, or hosts, and is responsible for end-to-end error recovery and flow control. It ensures complete data transfer.
Network
This layer provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions of this layer, as well as addressing, internetworking, error handling, congestion control and packet sequencing.
Data Link
At this layer, data packets are encoded and decoded into bits. It furnishes transmission protocol knowledge and management and handles errors in the physical layer, flow control and frame synchronization. The data link layer is divided into two sublayers: The Media Access Control (MAC) layer and the Logical Link Control (LLC) layer. The MAC sublayer controls how a computer on the network gains access to the data and permission to transmit it. The LLC layer controls frame synchronization, flow control and error checking.
Physical
This layer conveys the bit stream - electrical impulse, light or radio signal -- through the network at the electrical and mechanical level. It provides the hardware means of sending and receiving data on a carrier, including defining cables, cards and physical aspects. Fast Ethernet, RS232, and ATM are protocols with physical layer components.
802.3 standards and what layers of the OSI model they function at
Latency and propagation delay
collisions in ethernet- local, remote, late, jabber.
Long frame vs short frame
10 megabit, 100 megabit, and gigabit autonegotiation
Auto negotiation - Station sends out signal names and techniques
STP - Spamming tree protocol - what is it used for?
Techniques that switches use to reduce the number of collisions - need to know the specific names for it
Two methods store forwards and cut through how switches send frames
which devices breakup collisions and broadcast domains
TCP/IP Reference Model
Protocols that work with TCP/IP, ICMP, ARP, RARP what layer they work in of the OSI model
FTP - Which layer of the TCP/IP it works at
application
Protocol for the WWW
html
How ICMP, ARP, FTP, http work
IPV4 how it works , how many bits, classes of ip addressing
routed protocol vs routing protocol
IPX and netboui how they work
MAC Address table and routing table differences
What is an autonomous system?
A collection of networks under the control of one central administrator
Link state routing and distance vector routing
examples of routed and routing protocols
difference between exterior and interior gateway protocol
Routing protocol - RIP basics
Acronyms - TCP/IP, VPN, NIC, RJ, ECS, CSMA/CD, IPV6, VDP, RIP, OSPF
Which media is susceptible to electromagnetic interference and radio interference
Crosstalk - how it works
Speeds of ISDN, T1 Line, T3 Line
IP address host / node portions
Essay Question - Media Cat 5 single mode fiber optic etc.
Devices, which media would be appropriate and why. Router to switch, backbone etc.
