Considerations for Network Applications
A network
-Collection of devices that can talk to each other.
Applications that use the network
-Web browser and FTP
-Database application
-Instant messenger
-Email
-Online games
Considerations for network applications
-Speed
-bit byte (8 bits) kilobyte (1024 bytes) megabyte (1024 kilobytes) gigabyte (1024) terabyte (1024 gigabytes)
-Delay
-Voip has certain delay requirements for voice to be transmitted into data from one point to the next
-Availability
-How available is your network? Can it go down? If it goes down do you have a redundancy in place?
Network designs
-Bus (used thin net)
-Star (switch in the middle, all devices connect to the switch)
-Ring (token ring)
OSI Model
-Layer 1-4 are the only layers of the OSI model that are concerned in Cisco
-Layer 5-7 are handled by the OS; Windows, Linux, etc.
-Application: interfaces with the application and provides network access to the application
-Presentation: generifies the data (HTML) and encrypts services
-Session: starts and ends sessions/logically keeps sessions separate
-Transport: dictates how the data is sent and defines well known services (ports). (TCP/UDP) (source and dest port)
-Network: provides logical addressing (IP address)/finds the best path to a destination (source ip and des t ip)
-Data link: provides physical addressing (MAC) and ensures data is error free (source and dest MAC)
-Physical: provides access to the cable/electrical signals that represent ones and zeros
TCP/IP stack
-Application: Telnet, FTP, SMTP, DNS, RIP, SNMP
-Transport:TCP/UDP
-Internet: IP, ARP, IGMP, ICMP
-Network access: Ethernet, token ring, frame relay, ATM
IP address format
-4 numbers, each number 0-255
-Is always combined with a subnet mask and typically a default gateway
-The subnet mask dictates which portions of the ip address identifies the network and host
TCP
-Builds connections
-Uses sequence numbers (all packets have tags saying this is packet 1 and once it’s all
-Collection of devices that can talk to each other.
Applications that use the network
-Web browser and FTP
-Database application
-Instant messenger
-Online games
Considerations for network applications
-Speed
-bit byte (8 bits) kilobyte (1024 bytes) megabyte (1024 kilobytes) gigabyte (1024) terabyte (1024 gigabytes)
-Delay
-Voip has certain delay requirements for voice to be transmitted into data from one point to the next
-Availability
-How available is your network? Can it go down? If it goes down do you have a redundancy in place?
Network designs
-Bus (used thin net)
-Star (switch in the middle, all devices connect to the switch)
-Ring (token ring)
OSI Model
-Layer 1-4 are the only layers of the OSI model that are concerned in Cisco
-Layer 5-7 are handled by the OS; Windows, Linux, etc.
-Application: interfaces with the application and provides network access to the application
-Presentation: generifies the data (HTML) and encrypts services
-Session: starts and ends sessions/logically keeps sessions separate
-Transport: dictates how the data is sent and defines well known services (ports). (TCP/UDP) (source and dest port)
-Network: provides logical addressing (IP address)/finds the best path to a destination (source ip and des t ip)
-Data link: provides physical addressing (MAC) and ensures data is error free (source and dest MAC)
-Physical: provides access to the cable/electrical signals that represent ones and zeros
TCP/IP stack
-Application: Telnet, FTP, SMTP, DNS, RIP, SNMP
-Transport:TCP/UDP
-Internet: IP, ARP, IGMP, ICMP
-Network access: Ethernet, token ring, frame relay, ATM
IP address format
-4 numbers, each number 0-255
-Is always combined with a subnet mask and typically a default gateway
-The subnet mask dictates which portions of the ip address identifies the network and host
TCP
-Builds connections
-Uses sequence numbers (all packets have tags saying this is packet 1 and once it’s all