Ohne Titel

Transport Layer

• multiplexing - gathering data from multiple sockets, enveloping them into a header
• demultiplexing - delivering received segments into the correct socket
• UDP - mainly used for multimedia streaming, other uses are DNS and SNMP, its loss tolerant and rate sensitive
• Flow control
• Fixed windows - it processes 1-4 at a time and after they're processed, it asks more to be sent for processing
• Sliding windows - it processes one at a time and after it has been processed, ask for one more to be processed

Networking Layer

• Routing - routing a packet from source to destination
• Forwarding - routing a packet from input to the correct output
• Connection: network layer vs transport layer -
• IP addressing size & what parts does it have: 32 bit, subnet part 24 bit upper part and host part 8 bit lower part
• CIDR: Classless Interdomain Routing
• Organisation address: 200.03.01.00/020
• DHCP: is used to generate new IP addresses from other IP addresses that are not in use.
• DHCP messages:
• "DHCP request" msg
• "DHCP offer" msg
• "DHCP discover" msg
• "DHCP ack" msg
• NAT: Network address translation - its used to allow IP addresses from private network to operate on the internet
• Routing algorithm classification:

Networking Layer

• Link state vs Distance vector: link state computes the link cost to dest whilst distance vector computes the path cost to dest
• BGP: Border ...... Protocol
• In-network duplicate:
• flooding:
• control flooding:
• spanning tree:
• Reverse path forwarding:

Application layer

• Nodal delay:
• processing delay
• queueing
• transmission delay
• propagation delay:
• Traceroute program:
• App architectures:
• TCP & UDP:
• DNS: Domain name server
• HTTP: hypertext
• FTP: file transfer protocol
• SMTP:
• Mail access protocol:
• MIME:
• NVT:

Link Layer

• flow control: link vs transport layer:
• Ethernet:
• Star topology:
• Ethernet frame structure: reamble, type, CRC
• Link layer addresses: MAC address 48 bit and IP address 32 bit
• APR:
• TTL:
• Hubs:
• Switches:
• Error control options:
• no error detection
• error and discard
• error and retransmission
• FEC - forward error control

Link Layer

• BER: Bit error resolution
• EDC:
• Burst errors: burst errors are a number of errors in a short sequence
• Interleaving: its the process of fixing burst errors and making them into isolate errors
• Channel partitioning MAC protocols:
• Random access protocols:
• ALOHA, slotted ALOHA, CSMA, CSMA/CD

Physical layer

• Circuit switching:
• Packet switching:
• TDM:
• FDM:
• Different cables: Coaxial cable, fibre optic cable
• NRZ:

Security

• 3 types of firewalls:
• stateless
• stateful
• Cryptography types:
• ACL:
• IDS:
• SSL:
• Secure communication properties:

Wireless

• Elements of wireless network:
• Ad hoc mode:
• Hidden terminal problems: obstacle and fading. fixed by .............
• Wireless network taxonomy: