ict.ken.be

Delivering solid user friendly software solutions since the dawn of time.

TCP/IP Networking for Developers - Notes

Categories: Network Notes
TCP/IP Networking for Developers
Steve Evans - http://sevans.info
This was by far the worst Pluralsight tutorial I have ever seen, I am not an expert in networking and had hoped to learn a thing or two. Unfortunately, the course was not only very unstructured but also not very enlighting. Not even for a computer noob.
 
  • ipconfig
  • ipconfig /all | more
  • ipconfig /displaydns

  • c:\windows\system32\drivers\etc\hosts
  • You can put multiple hostnames on one line
  • 127.0.0.1 ken.be patrycja.pl test.be

  • No DHCP then 169.254.x.x

 

  • Change your ip logging to ipV6
 
Name resolution
  • nslookup ken.be
  • nslookup + enter, server 8.8.4.4
 
  • a-record transforms hostname into ip
  • set type=NS (nameserver)
  • set type=MX (mailexchange)
  • set type=CN (canonicalname or alias)
  • set type=AAAA (quad a) returns ipv6
  • wildcards records
 
A router connects different subnets
  • tracert
  • pathping
 

subnets

  • 255.255.255.node
  • 255.255.node
  • 255.255.255.240
 

routes

  • 0.0.0.0 means any ip address (netmask 0.0.0.0 to gateway)
  • 127.anything is always the localhost (netmask 255.0.0.0)
  • gateway.0 all that are on-link
  • 255.255.255.255 broadcast that doesn't cross router
  • route print
 
NAT (Network Address Translation)
  • Private Network Ranges
  • 10.0.0.0/255.0.0.0
  • 172.16.0.0/255.240.0.0
  • 192.168.0.0/255.255.0.0
 
Port Connectivity
  • TCP (Transmision Control Protocol) - request missing
  • UDP (User Datagram Protocol) - no check if received - no session
 
  • telnet ken.be 80
  • 400 Bad Request
  • port 1433 standard mssql
  • port 25 smtp
 
  • nmap -v servername (zenmap is win gui)
  • netstat -ano
 
Windows firewall
  • Log dropped packets
 
ICMPv4 protocol used by ping
Network Capture
Wireshark : right-click and follow tcp stream
Fiddler